RICHARD P. CINCOTTA & ROBERT ENGELMAN About Population Action International

Population Action International (PAI) is a research-based advocacy organi- zation that works to increase global political and financial support for effective population policies and programs grounded in individual rights. The organization seeks to make clear the linkages between population, reproductive health, the environment and development. At the heart of PAI’s mission is its commitment to the expansion of volun- tary family planning, other reproductive health services, and educational and economic opportunities for girls and women. Together these strategies promise to improve the lives of individual women and their families while also slowing the world’s population growth. PAI fosters the development of U.S. and international policy on urgent population issues through an integrated program of policy research, public education and political advocacy. PAI reaches out to government leaders and opinion makers through the dissemination of strategic, action-oriented publications, broader efforts to inform public opinion, and coalitions with other development, reproductive health and environmental organizations. Before January 31, 2000: 1120 19th Street, NW Suite 550 Washington, DC 20036 USA © Population Action International, 2000 After January 31, 2000: Material from this publication may be reproduced provided Population Action 1300 19th Street, NW International and the authors are acknowledged as the source. Second Floor ISBN: 1-889735-04-3 Washington, DC 20036 USA Library of Congress Number: 99-64886 Website: http://www.populationaction.org Photography: Front cover, Orang-utan, Jessie Cohen, National Zoological Park, Smithsonian Institution. Back cover, ©Rebecca Janes.

Acknowledgments 2

Population Action International This publication represents Population Action International’s first effort to work with geographic information systems, and in this endeavor the authors were greatly assisted by Kate Sebastian, Margret Bartels, Onyango Okello and Uwe Deichmann. We would also like to thank Lee Hannah and Ned Horning at Conservation International (CI) for their assistance with human disturbance data, Jorgen Thomsen, Tania Tarrar, Lata Iyer and Russell Mittermeier (also of CI) for their assistance with aspects of the biodiversity hotspots, and Aun Ling Lim at Population Reference Bureau for her assistance with national demographic infor- mation. Bruce Byers provided research assistance, and valuable reviews were offered by David Blockstein, Alan Bornbusch, Frederick Meyerson, Norman Myers and David Pimentel. We thank Dan Sperling for his edits to style and con- tent and Anne Marie Amantia and Victoria Stubbs for their assistance in tracking literature. Responsibility for the analysis and any views expressed in this publica- tion rest with the authors alone.

Geographic Information Systems Analysis: Jennifer Wisnewski Research Assistance: Bonnie Dye and Akia Talbot ContentsContents The Earth’s Biodiversity and Human Population ...... 4 Key Terms and Definitions ...... 5 Summary ...... 6 Box: Recommendations ...... 9 Box: Sylphion: A Natural Contraceptive and Its Loss ...... 10 Introduction ...... 11 Box: Relative Scarcity: Apes on the Edge ...... 12 I. Biodiversity In Brief ...... 15 Box: Relating Habitat Area to Species Numbers ...... 19 Box: The Red Queen’s Dowry ...... 20 Box: Banking on Genes to Feed the Future ...... 22 II. Four Waves of Human Influence ...... 24 Box: The Nature of Islands ...... 27 Box: An Epoch in the Making ...... 30

III. Nature Replaced: Prospects for Our Species ...... 33 3

Box: Human Fertility Change in the Highly Biodiverse Countries ...... 35 Nature’s Place Box: Bordering on Uncertainty: Considering the United Nations Population Projections ...... 36 Box: Population Momentum ...... 39 IV. The Role of Population Growth ...... 40 Box: Places Apart: Military Tensions and Biodiversity ...... 44 Box: Suburban Predators ...... 49 Box: Biodiversity, Property Rights and Population Growth ...... 52 V. Population Growth and the Global Biodiversity Hotspots ...... 56 Box: Key to the Global Biodiversity Hotspots and Major Tropical Wilderness Areas ...... 58 Box: Hotspot Population Profile – Madagascar ...... 65 Box: Hotspot Population Profile – California ...... 68 VI. Strategies ...... 69 Box: Learning from Biosphere 2 ...... 73 Centerpiece Map: People and Biological Diversity: Population in the Global Biodiversity Hotspots, 1995 Appendices Appendix 1: Data Sources and Methodology ...... 75 Appendix 2: List of Figures and Their Sources ...... 79 Earth’s Biological Diversity and Human Population

Existing Species Probably between 7 million and 15 million species Human Population World population, 1900: ~1.6 billion1 World population, 1950: 2.5 billion2 World population, 1999: 6.0 billion2

Threatened Species Assessed Species Proportion Listed as Threatened3 of total Vascular plants 33,798 12.5 percent Mammals 1,096 25 percent Birds 970 11 percent Reptiles 253 20 percent Amphibians 124 25 percent Fishes 734 34 percent

4 The 25 Global Biodiversity Hotspots Population Action International World land area (minus ice, bare rock): 134.9 million square kilometers4 Original extent of the 25 hotspots: 17.5 million square kilometers5 Area in hotspots remaining in natural vegetation: 2.1 million square kilometers5 World population, 1995: 5.7 billion people2 Population in the 25 hotspots, 1995: 1.1 billion people6 World population density, 1995: 42 people per square kilometer2 Population density in the 25 hotspots, 1995: 73 people per square kilometer6 2 World population growth rate, 1995 to 2000: 1.3 percent References Population growth rate in the 25 hotspots, 1995 to 2000: 1.8 percent6 1. J-N. Biraben, Population (Paris) 34,1 (1979):13. 2. UN Population Division, 1998. Units of Measurement 3. IUCN-World Conservation Union, 1996 1 kilometer = 0.621 miles (animals) & 1998 (plants). 4. UN Food and Agriculture 1 hectare = 2.47 acres Organization, 1998. 1 square kilometer = 100 hectares = 0.39 square miles 5. Conservation International, 1999. 6. Population data estimated by 1 kilogram = 2.2 pounds Population Action International. Key Terms and Definitions

Ecological Terms Extinction: in this report, the complete, Threatened species: species that have been Biodiversity (or Biological diversity): the permanent loss of a species to the planet assigned to one of three IUCN Red List diversity of living organisms and all the as a whole. categories—either vulnerable, endan- gered or critically endangered. interconnections that support life on Earth. Habitat: the particular environment in which a species or breeding population lives. Biological invasion: processes by which Demographic Terms Local biodiversity loss: in this report, the species become established in ecosys- Population growth rate: the percentage of loss of local breeding populations and/or tems to which they are not native. These the present population by which a popu- their habitat, and thus the likely loss of species are commonly called biological lation increases or decreases annually. invaders, invasive species or invading genetic variation and reserve individuals. Annual growth increment: the number of species. They are often weeds, pests and Protected area: a geographically defined disease-causing organisms. people added to a population or subtract- area that is regulated and managed to ed from it annually. Breeding populations: groups of individual achieve specific conservation objectives. Population momentum: the tendency of pop- plants or animals that tend to reproduce Species: a group of organisms that, ulation growth to follow past growth among themselves and much less fre- because of close genetic and physical trends for several decades, despite imme- quently with individuals from other similarities, can naturally mate with each diate changes in fertility that could even- members of the same species. As impor- other and produce viable offspring (indi- tually stabilize population or even tant sources of migrants and their genetic 5 viduals that can also reproduce natural- reverse its direction of change. variability, these separated sub-popula- ly). Within species are often other levels Nature’s Place Population density: the number of people tions can prove critical to the survival of of similarity, including sub-species, vari- inhabiting an area of land (expressed as a species as a whole. eties, and breeding populations. Organisms people per square kilometer in interna- that reproduce only through asexual Domesticated species: species in which the tional publications). evolutionary process has been manipu- means (such as micro-organisms that lated by humans to meet human needs. reproduce by dividing or budding) are Total fertility rate: the average number of sometimes difficult to separate using the children that would be born alive to each Ecosystem: a dynamic complex of plants, species concept. woman if her reproductive experience animals and micro-organisms and their were to turn out the same as that of non-living environment that interact as a Speciation: the processes by which new women of all reproductive ages who are unit. species are established. currently members of the population. Endemic species: those species that occur Sustainable use: the use of components of within a restricted range. Outside that biological diversity in a way and at a rate Sources: restricted range (such as an ecosystem, that does not lead to its long-term “Biodiversity Notes,” Newsletter (Madison, WI: The Biodiversity Project, Winter 1999). island, or within country boundaries) an decline, thereby maintaining its potential endemic species is found nowhere else to meet the needs and aspirations of Convention on Biological Diversity, UN present and future generations. Conference on Environment and Development, on Earth. Rio de Janeiro, June 5, 1992. SummarySummary

he world’s biological wealth is dwin- Human Activity and dling. Earth—the only location in the Biodiversity universe that we know supports life— is being transformed into a world that Scientists are becoming increasingly con- is genetically poorer. The loss is irre- vinced that human beings have caused Ttrievable, and its roots lie in the spectacular ecosystem change and species extinction success of a single species: us, Homo sapiens. almost since our own species emerged. The disappearance of species, proceeding Between 50,000 and 10,000 years ago, as thousands of times faster today than in the early populations of humans expanded across pre-human past, is still accelerating and is the continents, more than 200 species of likely to advance even more rapidly in the 21st large animals disappeared forever. Then, century. No one can know when the process between 1,500 and 500 years ago, as human will end, or what the world of nature will look populations reached the farthest oceanic 6 like when it does. islands, over 1,000 species of island birds

Population Action International Hopeful signs do brighten this dark went extinct. Today’s wave of extinctions, prospect, however. Among the most hopeful is however, is even more extensive. Moreover, it that human population may well reach a is fundamentally different from its two prede- plateau or peak by the middle of the 21st cen- cessors in ways that relate strongly to the tury. The pressure of human activities on pervasiveness and size of today’s human remaining habitats could reach a maximum population: around the same time—and then, perhaps, • For the first time, human activities are begin to subside. affecting species of all types and habits, Among the most pressing questions are: at all points of the globe, and pushing Does human population growth really matter many toward extinction. Scientists project to species loss? Can policies and programs sig- that at least half of all living species could nificantly influence human population trends, ultimately disappear due to habitat loss and can they do this while upholding the basic alone, creating a mass extinction on a scale human right of couples and individuals to comparable to those that have ended past make their own decisions about reproduction, geologic eras. free from interference? The evidence shows • Apart from habitat loss, other agents of that the answer to all these questions is yes. human-caused extinction are now at work. Even more species could disap- an important determinant of the scale species. These organisms, which pear as a result of pollution, overhunt- of humanity’s use of natural resources include domestic and other species ing, overfishing and inadvertent intro- —resources upon which other species that thrive in human-dominated duction of exotic species into weak- depend, as well. Population growth, ecosystems, are themselves often prin- ened ecosystems. Hanging over the along with increasing per capita con- cipal agents of ecological disruption future of all life is the puzzle of how sumption, has played a key role in the and biodiversity loss. global climate will change in coming development of human-dominated Early stabilization of human popula- centuries as a result of human influ- ecosystems in which the survival of tion would not by itself act as a break- ences, and how these changes will wild species is often precarious. And water against the current wave of extinc- affect ecosystems and the species they recent population growth has made tions. Nonetheless, it is arguably a neces- support. biological conservation efforts more sary condition for saving more than 10 • Not all species are at risk, however. difficult, more expensive and more percent of the earth’s natural ecosystems Evolution is resilient. A small percent- likely to conflict with human needs. in perpetuity. And that achievement, age of species—from pigeons, to • The growth of our species’ numbers ecologists argue, will be needed to avoid weeds, to microbial parasites—have is tightly coupled to rising demand losing more than half of the planet’s proliferated beyond their pre-human for food and shelter. Increasing the remaining plant and animal species. numbers or ranges. Rapidly evolving supply of these essentials, by whatever pests and disease-causing organisms means, affects biodiversity. Agricultural Hotspots: Population could swell their ranks. Humanity expansion and urban sprawl play the itself, with more than 30 times the largest discernible roles in the loss and Pressures in the Most population density it ever could have fragmentation of the world’s forests Biodiverse Places 7 achieved without agriculture, now and wetlands, and contribute signifi- The emerging technology of geographic appears to have become the central cantly to river and coral reef siltation. information systems (GIS) opens up new Nature’s Place organizing reality around which non- Intensified agriculture and urban con- possibilities for analyzing the distribution human life will evolve. centration are leading contributors to and richness of species, including our water-borne pollution. And jointly, own species. Several key findings emerge Population and Biodiversity agriculture and domestic activities in this first-ever effort to utilize this tech- account for over three-quarters of all nology in a Population Action International The full range of connections between water withdrawn for use from reser- report: local population growth, the influence of voirs and aquifers. These are also the distant consumers, changing ecosystems • More than 1.1 billion people now live primary beneficiaries of dam-building, within the 25 global biodiversity and the loss of species is complex, con- which is one of the top two causes troversial and in need of more research. hotspots, described by ecologists as (along with biological invasions) of the most threatened species-rich Nonetheless, biologists agree on several freshwater species extinctions. key points: regions on Earth. In 19 of these • When considering human popula- hotspots, population is growing more • Population growth is among a hand- tion growth, analysts tend to over- rapidly than in the world as a whole. In ful of underlying conditions deter- look the parallel growth and prolifer- one hotspot (the Caucasus), population mining the type and intensity of ation of populations of organisms is decreasing moderately. While the human activities that lead to biodi- that are closely associated with our hotspots extend across some 12 percent versity loss. Population size itself is of the planet’s land surface, by 1995 Congo River Basin, and the New Population and Hope they were home to about 20 percent of Guinea-Melanesia complex of islands. The evidence of recent demographic the world’s population. All together, these areas cover around research suggests that couples the world 6 percent of Earth’s land surface. • Around 75 million people, or 1.3 per- over, and especially younger women, Population in the tropical wilderness cent of the world’s population, live today desire later childbirths and fewer areas is, on average, growing at an within the three major tropical children than ever before. Both desires— annual rate of 3.1 percent, over twice wilderness areas: the Upper if put into effect—contribute powerfully the world’s average rate of growth—a Amazonia and Guyana Shield, the to the slowing of population growth, product of rapid migration and high now averaging 1.6 percent annually for rural fertility rates in these regions. less developed regions of the world and • In most hotspots located in devel- 0.3 percent for the developed regions. oped countries, populations are pro- The growth of our species, once the FIGURE 1 jected to grow for several decades to object of environmental fears, has Possibilities in the Demographic Future come. Past and present migration into instead shown itself in the past decade these areas is the major factor in this to be among the more resolvable of 20 continued growth, specifically in the environmental concerns. 18 High Projection U.S. states of California, Florida and A plateau or peak in human popula- 16 Hawaii, and in western Australia and tion by the middle of the new century is in New Zealand. Much of this migra- 14 possible. But this is likely to occur only tion is internal, with more people PAST PROJECTED if developed and developing countries 12 moving to warmer climates and 8 renew their commitments to the princi- 10 coastal areas. Significant international

Population Action International ples—and the shared investments— migration has also been involved, to (billions) 8 agreed to in 1994 at the International 6 varying degrees, much of it with ori-

POPULATION Conference on Population and Low Projection gins in developing countries. 4 Development in Cairo. Much of what society and conserva- An early halt to human population 2 tionists will need to accomplish to save growth will not end human-caused 0 | | | | | | | species will have little to do directly extinctions. Conservationists will contin- 1950 1975 2000 2025 2050 2075 2100 with population change. Population ue to contend with our species’ unprece- analysis can, however, provide a meas- dented densities, its geographic range and Human population could peak midway through the ure of the risks that most species will mobility, its need for natural resources 21st century, or continue growing with a wide range of plausible outcomes. The path that population face. For as population grows and as and ways to dispose of wastes, and its takes will likely be strongly influenced by the way in additional land, water and waste-absorb- use of technologies. The possibility of which nations order their priorities during the com- ing sinks are needed to support these world population stabilization, in combi- ing decades, and the progress women achieve toward individuals, some conservation options nation with modest decline in some economic and reproductive self-determination. necessarily fall by the wayside. regions, nonetheless offers among the Source: Data from UN Long-Range Projections, 1998. greatest hopes for the future of species and ecosystem conservation on a human- dominated planet. Recommendations

ach of us can take action to preserve 1994 International Conference on tion possibilities—the high and low the planet’s wealth of living species. Population and Development support scenarios projected by the United EThis report’s recommendations are and amplify other measures to conserve Nations—rather than the medium sce- addressed to policymakers, to scientists Earth’s complex web of life. nario alone. There are immeasurable and conservationists, and to the general • The public and private sectors should possibilities for unexpected demo- public. Specifically, they include the fol- cooperate to diminish the environmental graphic changes, even in the regions lowing: impacts of the expansion of agriculture where up to now there has been little • The conservation of biological diversity and housing. Significant investments in improvement in women’s status and lit- should be elevated to a high priority by research and improved standards in engi- tle decline in fertility rates. donor agencies, nations and communi- neering and zoning for these sectors • Consumers should learn about and con- ties. While innovative conservation pro- could help minimize the conflict sider the role of their purchases, their grams deserve support and funds, there between conserving biodiversity, and pets, and their daily activities in put- is a pressing need to encourage broader much-needed efforts to alleviate poverty ting biodiversity at risk. They should understanding of biodiversity and its and to accommodate the population inform themselves about and consider value to society. To further this objec- growth that occurs during the next sev- how their lifestyles and their political tive, governments and donors should eral decades. choices influence native species and work to expand the ranks of biodiversity 9 • Where organizations work in remote rural ecosystems. scientists and environmental educators Nature’s Place areas to promote biodiversity conserva- • Couples and individuals should consider in the species-rich tropical countries. tion, conservationists should consider the impact of their reproductive deci- • The Convention on Biological Diversity, cooperating with qualified providers of sion-making on the well-being of their an international agreement aimed at reproductive health services. They can do communities and of the world as a maintaining the planet’s biodiversity so without jeopardizing their mission in whole. and equitably sharing its benefits, conservation by working as part of The survival of anything like the cur- deserves the support of all nations and broad-based efforts to promote commu- rent panoply of plant and animal species peoples. Negotiators seeking to improve nity development, address basic human will depend not only on investments it and further its progress should con- needs, and improve the management of made today in biological conservation sider the interactions between species natural resources that sustain human programs, but also in human develop- survival and human population dynam- and non-human life. ics. Through their impact on population ment efforts that end up, as a side bene- • In research publications and other com- growth and on the capacity of women to fit to their main purposes, slowing the munications, scientists and educators manage their own lives, the social growth of human population. should use the range of future popula- investment strategies called for at the Sylphion: A Natural Contraceptive and Its Loss

single wild herb, a fennel-like plant in the car- grows more acute each year. Whatever lessons syl- rot family, could stand as a symbol of the major phion might have offered to developers of modern Athemes of this report, except for one fact: the contraception, however, are lost. No one knows what plant no longer stands at all, having gone extinct active ingredient in the herb allowed Mediterranean around the height of the Roman Empire. women to manage their own fertility. No one knows Roman and Greek chronicles reported that syl- how safe or effective it was, or even how the herb phion (Ferula historica) once grew in abundance in was prepared. the hills near Cyrene, a Greek city-state founded in All we can be sure of is that many women in the Greek Colonization the 6th Century BC along the coast of what is now classical world wanted very much to postpone preg- 6th Century BC Libya. Cyrenian women valued nancy and plan their families. Sylphion’s value sylphion as an herbal antifertil- climbed until it was said to have commanded its Black Sea MACEDONIA ity drug. It was, in fact, the weight in silver. Without substitutes or the capacity GREECE BYZANTIUM ALBANIA oral contraceptive of the classi- to domesticate or hybridize the wild herb, commercial nd rd Aegean cal world, and contraception traders over-harvested it. Around the 2 or 3 cen- Sea ASIA ATHENS was its only recorded use.1 tury AD, sylphion disappeared. ESPHESUS SYRACUSE SPARTA The case of sylphion reminds us that women’s 10 As knowledge of sylphion’s PHOENICIA properties spread throughout interest in managing their own fertility is ancient.

Population Action International CYPRUS Mediterranean Sea the Mediterranean basin, how- The herb’s extinction speaks of humanity’s longstand- ever, the herb was transformed ing but fragile economic association with biodiversi- CYRENE from a home remedy, largely ty. It also demonstrates the importance of conserving Naucratis CYRENAICA controlled by women them- critical biological resources for ourselves and for our EGYPT AFRICA selves, into one of the principal posterity. As in the case of sylphion, we may not commodities of Cyrene’s foreign know the full price of our loss until it is too late. trade, controlled by men. Evidence of sylphion’s eco- nomic importance is its silhouette on the face of References Cyrenian four-drachma coins. The 4th century BC 1. J.M. Riddle, Contraception and Abortion from the Ancient World to the Renaissance (Cambridge: Harvard University physician Hippocrates records Greek and Syrian Press, 1992). attempts to cultivate the herb on home ground and 2. J.M. Riddle, J. W. Estes, American Scientist 80, May/June cut into the Cyrenian market. The attempts failed, (1992): 226-233. and sylphion remained endemic to Cyrene.2 Today, unlike in Roman times, over 3 billion adults and adolescents around the world are in or are entering their reproductive years. The need for a variety of safe and effective contraceptive methods IntroductionIntroduction

ever before, in 3.5 billion years of density and growth, aspects that will clearly life on Earth, has a single species figure in their biological future. chipped away large portions of the As is the case with most environmental entire earthly array of life. Yet that issues, there is some disagreement about the is what human beings are doing nature and scale of the threat to biodiversity Ntoday, however unintentionally. If most of the today. Few if any scientists, however, would trends evident in the 20th century continue, it argue that there is no threat at all. As this is hard for most biologists to project anything report points out, humanity’s hand in the other than a much less diverse—and there- extinctions of large land mammals during the fore less wondrous—web of life in the com- late Pleistocene Epoch, and of oceanic island ing century and beyond. birds during the last two millennia is virtual- There is one trend, however, that suggests ly certain. But never has Homo sapiens hope for the future of the world’s complex pushed so many species, of so many types mix of species and ecological systems. The and located in so many parts of the world, 11 growth of the human population is slowing toward the biological thresholds of existence. Nature’s Place down, faster at the close of the 20th century And this push has been rapid. Most popula- than most demographers had previously tions of these now-threatened species were expected. Whether and how fast that trend apparently hardy and viable at the beginning will continue, however, depends critically on and even the middle of the 20th century. decisions made today. Defying the world’s preoccupation with This report, the sixth in a series on popu- the growth of financial wealth, conservation- lation and critical natural resources, considers ists around the world work to hold back the how population is changing, how society relentless erosion of the biological and genet- might influence these trends, and what ic wealth inherited from eons of evolution. impact future population change might have The overarching term for this natural wealth on the conservation of species. The report is biodiversity, described as the “diversity of surveys the world’s highest-priority regions life and all the interconnections that support for biological conservation, the 25 biodiversity all life on Earth.”1 hotspots and three major wilderness areas. It There is little optimism in the scientific quantifies each region’s human population and conservation communities that the cur- Relative Scarcity: Apes on the Edge

hile our own popula- less numerous. No more than a few tens of References tion is growing steadi- thousands of individuals exist, about the 1. IUCN Red List of Threatened Animals ly, those of our closest equivalent of human population in a medi- (Gland: IUCN, 1996). W 2. UN Statistics Division, Demographic um-sized town. In fact, the number of biological relatives, the great Yearbook (New York: United Nations, apes—the non-human members human beings born each day—some 1998). of the family Hominidae—have slid 350,000—is greater than the current popu- 3. M-C. King and A.C. Wilson, Science ©Dunn Photographic precariously toward extinction. Over the lations of all other great apes combined. 188 (1975): 107-116. 4. A.L. Rose, African Primates, Winter past half-century, the population numbers Much of what science has learned about (1998); G. Streiker, “Poachers Killing of three out of our four closest relatives— human physiology and behavior comes from Gorillas, Chimps for Bush Meat chimpanzees, bonobos and gorillas—have observations of primates, particularly of the Delicacy: Activists Blame Logging declined by at least half, earning these apes. This is hardly surprising; more than 98 Companies for Problem,” CNN species an endangered status from the percent of human DNA is identical to that of Interactive, Dec. 30, 1998. 5. F. de Waal and F. Lanting, Bonobo: 1 3 IUCN-World Conservation Union . The orang- chimpanzees and bonobos. Yet like selfish the Forgotten Ape (Berkeley: Univ. of utan’s population has slipped between 20 big brothers in a dysfunctional family, California Press, 1997), p. 172. percent and 50 percent over a similar peri- humans are these animals’ greatest threat. 6. J. F. Oates, “African Primates,” Status 12 od. Considered vulnerable to extinction in Some experts believe that the growing bush- Survey and Conservation Action Plan (Gland: IUCN/SSC Primate Specialist Population Action International IUCN’s 1996 appraisal, the orang-utan is meat trade—the uncontrolled harvesting of Group, 1996). now even worse off—possibly down to half wildlife, and the butchering and marketing 7. S. Saunter, World Conservation its 1996 numbers—following the past two of their meat—could eliminate all viable Society, personal communications, particularly destructive years of forest fires populations of African apes within the next May 1998. 8. J.S. Hall and others, Oryx 32, 2 50 years.4 Despite the acute problem of on the islands of Borneo and Sumatra, and (1998): 122-130. the economic crisis and political unrest that hunting pressure, the clearing of forest may 9. C. Yeager, Conservation International, continue to plague Indonesia.10 yet prove the ultimate undoing of efforts to personal communications, May 1999. Population sizes of the various species save ape species. 10. G. Streiker, “Asian Economic Crisis Today Homo sapiens is the greatest of Could Spell End for Orangutans,” CNN of great apes are tiny fractions of our own. Interactive, March 5, 1999. Even the most abundant species, the chim- the great apes. Humans share the greatest 11. H.D. Rijksen and others, Our panzee, now numbers well below 200,000 in responsibility for these species’ demise, and Vanishing Relative? The Status of Wild the wild.6 In the United States alone there can reap the greatest benefits for conserv- Orang-utans at the Close of the Twentieth Century (Wageningen: are 78 cities with populations greater than ing them. But unless we fully understand Tropenbos, 1998); C.P. van Schaik, that figure.2 The other three great apes— this greatness, a day may come when— Duke Univ., personal communications, the bonobo (a genetically distinct species beyond the walls of zoological parks and labo- May 1998. formerly known as the pygmy chimpanzee), ratories—we are the only living member of the orang-utan and the gorilla—are even our Hominid family. FIGURE 2 Population and Status of the Great Apes, 1999

The degree of extinction threat increases from vulnerable, to endangered and then to critically Species, Scientific Name Population Size Degree of endangered—the latter category holding the most subspecies, scientific name (~ = approximately) Extinction Threat seriously threatened species on IUCN’s Red List. Bonobo 10,000 - 25,0005 Endangered Pan paniscus

Chimpanzee 100,000 - 150,000 Endangered Pan troglodytes (~2,500 in captivity) eastern chimpanzee More than 5,000 in the Democratic Republic Endangered Pan troglodytes schweinfurthi of the Congo (former Zaire); ~8,000 in Uganda, Rwanda, Burundi and Tanzania6

central chimpanzee ~80,000, chiefly in Gabon and Congo. Endangered Pan troglodytes troglodytes Parts of habitat still not surveyed.6 western chimpanzee No more than 12,0006 Endangered Pan troglodytes verus

Gorilla 40,000 - 65,000 Endangered 13 Gorilla gorilla Nature’s Place mountain gorilla ~6507 Critically Endangered Gorilla gorilla beringei Grauer’s gorilla ~17,000 (8,600 - 25,500)8 Endangered Gorilla gorilla grauerii

western lowland gorilla 30,000 - 40,0007 Endangered Gorilla gorilla gorilla

Orang-utan * ~38,500 *Vulnerable * estimated prior to 1997-98 fires; (present popula- Pongo pygmaeus tion could be from 25,0009 to as low as 15,00010)

Sumatran orang-utan * ~7,50011 (subspecies not evaluated) Pongo pygmaeus abelii Borneo orang-utan * ~31,00011 (subspecies not evaluated) Pongo pygmaeus pygmaeus

Human ~6.0 billion The IUCN-World Conservation Union classifies humans as members of the family of species referred to as the Hominidae—or the great apes, as they are more commonly known. No other ape, nor any primate, can claim near the geographic range or population Homo sapiens that humans can. And all species of great apes, except our own, are listed as threatened with extinction. rent threat to biodiversity can be eased environmental degradation, extinction of References any time soon. In a recent Harris Poll, a species is a loss no future can remedy. 1. “Biodiversity Notes,” Newsletter nearly 70 percent of biologists polled It is, for that life form, a one-way trip to (Madison, WI.: The Biodiversity said that they believed a mass extinction oblivion, despite the fantasies of recent Project, Winter, 1999). 2. Louis Harris and Associates, is under way. A similar proportion pre- popular cinema. “Biodiversity in the Next dicted that up to one-fifth of all living Millennium,” Survey (New species could disappear within the next Why This Study? York: American Museum of 30 years.2 When scientists consider cur- Natural History, 1998); J. Warrick, “Mass Extinction rent rates of land and aquatic conversion Just as few scientists doubt the threat to non-human species is real, few would Underway, Majority of from non-human to human uses, they Biologists Say,” The Washington estimate that thousands of species blink argue that the threat is unrelated to the Post, Tues., April 21, 1998, A-4. out each year. recent growth of human population and Most of the plants, insects, aquatic its contribution to the scope and scale of Unlike most other forms and marine creatures, and microbes that human activity. Yet little research has so vanish do so before scientists can record far explored the complex connections between the threat to biodiversity and the of environmental their existence. But every few months, one (or more) of the high-profile species size and growth of human population. —a bird, mammal, amphibian or reptile This report is designed to help fill degradation, extinction known to science—is officially dropped that gap, to distill the evidence and liter- from the catalogue of earthly inhabitants. ature for policymakers and other non- of a species is a loss no Only a few cases of extinction are well scientists, and to contribute original 14 documented. The extinction of 12 of analysis to the issue. In the analysis, we

Population Action International employ geographic information systems future can remedy. Guam’s 14 remaining land bird species, which succumbed to the predation of the (GIS) technology, an approach to geogra- exotic brown tree snake during the past phy that uses digital information made 50 years, is such a case. The elimination possible by surveys, remote sensing and of over 200 freshwater fish species in other means. The central portion of this East Africa’s Lake Victoria is another. report uses GIS to make first-ever esti- Since Earth first spawned life, global mates of population size and growth biodiversity has been depleted and rates in the world’s most biodiversity- renewed several times. The record left rich hotspots. The data that result pro- by fossils tells us that several million vide an idea of where progress in sound years of evolution can generate sufficient population and other human develop- diversity to fill the ecological niches ment policies will be needed to bring abandoned by the extinct. But this is human population trends into balance meaningless to societies that strain even with the world’s most diverse and valu- to look a matter of years or decades into able ecosystems. the future. Unlike most other forms of 1.1. BiodiversityBiodiversity inin BriefBrief

[We are] conscious of the intrinsic iological diversity—or biodiversity—is along with plants that survive in suburban the sum total of life’s physical expres- parks, on roadsides and on lawns. These value of biological diversity and of sion and genetic potential, embodied species contribute little to the global pool of the ecological, genetic, social, eco- in the array of organisms now alive. genetic variability. In fact, they generally In a practical sense, biodiversity is detract from it. Biological invaders are nomic, cultural, recreational and aes- Bthe living savings bank for Earth’s successful blamed for pushing out native species and thetic values of biological diversity genes, a bank that holds some 3.5 billion disrupting the flow of energy and vital nutri- years of life’s solutions to the problems of ents through both natural and agricultural and its components, conscious also of surviving and competing on our planet. ecosystems.1 A recent study calculated that the importance of biological diversity Those genetic savings alone make biodi- alien weeds, introduced animals (mostly versity an exceedingly valuable asset—but insects) and infectious diseases of foreign ori- for evolution and for maintaining life there is more to this natural resource. With it gin cost the United States well over $100 bil- come cellular processes that reshuffle and lion a year.2 sustaining systems of the biosphere. alter the expressed and hidden genetic varia- If merely counting species is an inade- 15

tion produced during evolution, processes quate indicator of biodiversity, then what Nature’s Place Opening words of the preamble to the that are essential to meeting challenges yet to defines local biodiversity? The short answer Convention on Biological Diversity, be posed. Biodiversity also encompasses the is: the status of native species. In conserving physical, chemical and behavioral relation- the complement of native species, biologists Rio de Janeiro, June 5, 1992 ships that have evolved between co-existing assume that each contributes, in some large species, and the ecosystems and biotic cycles or small way, to the complex properties of that embody these relationships, protect the ecosystem in which it resides—the them and promote their continued evolution. ecosystem’s web of food relationships, its To assess biodiversity in any one locality, ability to capture energy and be productive, biologists often run surveys to determine its ability to cycle nutrients and water, to how many species live there. A simple count, exclude exotic species, and to recover from however, can be misleading. For example, a droughts, storms, infestations or pollution.3 large portion of the species we encounter are Ecologists express concern about activities biological invaders, exotic species, many of that upset the mix of species, eliminate them adapted to environmental distur- breeding populations and increase the risk of bance—as are a majority of the common extinction. These scientists rarely can predict backyard birds, rodents and insects that the long-term implications of removing or inhabit our garbage and invade our homes, replacing each species from any one ecosys- tem. Surveys and field experiments have to be universal, ecological studies have ecosystems but are missing from the fos- demonstrated that the removal of certain yielded only a handful of basic princi- sil record, paleontologists guess that keystone species, often large predators ples that can be successfully applied something like 5 billion species have that keep other species’ populations in from one ecosystem to the next. In the lived on Earth.8 Only two in every thou- check, can radically change ecosystems. present winnowing and rearrangement sand of the world’s ever-existing species, In other cases, however, species have of the biological world, surprises are however, share the planet with today’s 6 been eliminated with little observed common and often very costly, as illus- billion human beings. short-term ecological disruption. Just one trated by the over $100 million in dam- From the pre-human fossil record, pale- in a hundred transplanted exotic species age already wrought by invading zebra ontologists estimate that a mass extinction go on to produce major biological inva- mussels on North American waterways.5 has unfolded on average once every 26 sions—and there are few clues alerting million years. Five major mass extinctions biologists as to which one that will be.4 and roughly another 20 minor pulses of Unlike physics, whose laws we take How Many Species Are There? extinction have occurred since animals The species is biodiversity’s “currency.” It emerged in the fossil record around 600 is the lowest level of classification at million years ago. These were geologically

FIGURE 3 which there are good chances that organ- brief periods during which from 15 per- isms with different descriptive names will cent to as much as 90 percent of animal Counting Earth’s Species also possess very basic genetic differ- species disappeared.8 ences. About 1.5 million species have Beetles Mass extinctions are presently thought Butterflies & moths been named and described in museum to have been caused by radical changes in Ants, bees & wasps collections.6 The most current scientific sea level, abrupt climate shifts, and colli- 16 Flies estimates of total living species range sions with comets or other cosmic debris.

Population Action International Other insects between 7 and 15 million, though esti- All told, these pulses account for roughly Spiders Other arthropods mates higher than 30 million species 60 percent of extinctions.8 The last major Crabs & relatives emerge from justifiable assumptions and mass extinction, 65 million years ago, saw Shellfish, squid and relatives estimations. Around 10 million is a rea- the end of dinosaurs and large marine rep- Described species Roundworms sonable guess for the present, and reason- tiles, and permitted the evolution of a new Other invertebrates Estimate of species Mammals, Birds, Amphibians, remaining to be described able guesses will have to do. Currently sci- assemblage of species, including our own. Reptiles & Fish Plants entists are finding and describing about Algae 15,000 species a year. So if 10 million Fungi species indeed exist, it would take over 6 What Species Amoebas & other protozoans centuries, at current assessment rates, just Are Alive Today? Bacteria Viruses to make a proper inventory.7 From a geological perspective, we live our • • • • • • 0 500,000 1,000,000 1,500,000 2,000,000 2,500,000 So far, some 250,000 extinct fossil lives in the Cenezoic Era, often called the NUMBER OF SPECIES species have been described. But the fos- Age of Mammals. In fact, mammals and sil record presents a notoriously small all other vertebrates (that is, animals with According to the latest scientific estimates, the number of Earth’s species range from 7 million to 15 million. In this and unbalanced sample of the earth’s backbones) presently account for only graph, a total of around 10 million species is assumed. Less biological past. Based upon educated around 40,000 species, or fewer than 1 than 1.5 million have been identified, and relatively few of guesses of what types of species would percent of all species. Plant life, consisting these have been studied to any depth. have been present to fill out ancient of flowering plants, conifers, mosses and Source: Adapted from N.E. Stork, 1992. ferns, probably make up fewer than 5 per- species, however, live in such extreme species are exiting much faster. Based on cent of all species, or about 300,000 environments. Many more inhabit savan- records of extinction among the best- species. Arthropods—a group that nas, the tundras, or live in the open seas. studied types of animals, British ecologist includes the insects, crustaceans, spiders, Still higher concentrations of species Stuart Pimm and colleagues calculated mites, centipedes and their relatives—are spend their lives in the grasslands and extinction rates during the past century to by far the most diverse and widespread of coniferous forests of temperate latitudes; range from 100 to 10,000 species per year all groups of organisms, and they are not and even more survive in marshes and (again, assuming 10 million species well studied. They make up around 40 swamps, rivers and lakes, in ocean tidal exist). That rate is between 100 and 1,000 percent of living species. zones and around nutrient-rich marine times faster than the background rate of Biologists still have a world of discov- shoals. The largest concentrations of ter- species extinction.11 ery awaiting them in invertebrate diversi- restrial biological diversity live where it is What if all species presently listed as ty. There are enough undescribed mol- warm and humid, and where such condi- threatened by IUCN-World Conservation lusks, echinoderms, jellyfish, worms and tions are seasonally quite stable: in the Union were to go extinct in the next cen- Though comprising only their relatives and other backboneless rainforests of the tropics. Though compris- tury? Then extinction rates would multi- creatures to fill a few hundred museum ing only 2.3 percent of the entire surface ply another 10 times over current rates, to 2.3 percent of the entire cases and bookshelves. And there are of the earth,9 rainforests probably hold 1,000 to 100,000 species per year.11 This 10 likely significant payoffs for describing more than 50 percent of all species. alarming projection matches other project- surface of the earth, many of the hundreds of thousands of Tropical coral reefs—sometimes called ed rates, by leading ecologists, based on species of fungi, protozoa, algae, bacteria the “rainforests of the oceans” for their recognized mathematical relationships and viruses that remain unknown. richness of species—may run a close sec- between habitat loss and species loss.12 rainforests probably hold ond. Worldwide there are about 600,000 Several decades of biological losses near Where Are They? square kilometers of reefs, comprising the high end of this range would probably more than 50 percent of 17 roughly 0.1 percent of Earth’s total surface. put at risk the planet’s major biological Nature’s Place Life has spread to virtually every corner As many as 950,000 species may inhabit and geochemical cycling systems. all species. of our planet. Species of archaebacteria coral reefs globally, though as few as 10 thrive at near-boiling temperatures in hot percent have been described.9 springs in North America, while related How Many Species species live in the cracks of ice-bound Will Remain? Antarctic lakes. Thousand year-old wel- How Fast Is Earth How many of today’s species survive the witschia plants bloom on the dunes of the Losing Species? current wave of extinctions depends on African Namib, one of the hottest and dri- As a rule, extinctions happen. Paleontologists how quickly nations recognize the values est of Earth’s deserts. At the same time, estimate the background rate of species of biodiversity, and how assiduously gov- foot-long Jericho worms and bacteria-eat- extinction—the long-term extinction rate ernments, organizations and individuals ing brachyuran crabs feed at the mouths exhibited prior to humanity’s influence— work for its conservation. It also depends of volcanic vents four kilometers beneath at between 1 and 10 extinctions each critically on the future of human popula- the ocean surface under hull-crushing decade among every million fossil species. tion and human behavior. The highest pressures, bereft of any sunlight and Assuming 10 million species are alive UN population projections—and even bathed in the searing acidity of concen- today, scientists can expect 1 to 10 species they assume declines in human fertility trated hydrogen sulfide. to go extinct each year from all forms of from present levels—suggest a world of Relatively small percentages of today’s life, visible and microscopic. In fact, humanity that arguably could spare little room for nature without the widespread only the number of species, but the num- nomic thinking, a meeting of biological use of extraordinary technology, and the ber of diverse groups of plants and ani- and economic mindsets, argues that the implementation of environmentally- mals, each distinct in form from one global economy, swelled by population enlightened governance of unimaginable another (what biologists call genera and growth and increasing per capita con- capacity. families)—required at least 5 million sumption, has grown so large, so If only 10 percent of each type of natu- years, and in some instances up to 100 demanding and technologically capable, ral habitat eventually remains (and that million years.14 Homo sapiens has been that virtually nothing can escape it. appears to be an optimistic projection for around for some 250,000 years. Nature As economist Herman Daly and many moist tropical forests), around 50 recovers, but not on a time scale relevant ethicist John Cobb have observed, “nat- percent of all species are projected to sur- to human society. ural selection is giving way…to eco- vive. If that habitat is fragmented—left in nomic selection.”17 What is not recog- small isolated pieces (and much of the nized as a valuable service in the mar- remaining habitat already is)—then there And What is ketplace, or is not valued by regulation If only 10 percent of could be less. If species invasions contin- Biodiversity Worth? and enforced protection, will ultimately ue, and they appear to be increasing with Accounting for annual economic produc- be traded for or substituted with some- thing afforded a higher value. This call- each type of natural globalized trade and weakened ecosys- tivity of commercial fish species or tim- tems, then perhaps our descendants will ber species, or even for certain genes to-arms has prompted several estimates encounter even fewer survivors, and even used in crops or in pharmaceuticals is a of nature’s values. According to one habitat eventually fewer still from over-harvesting, pollution straightforward exercise. Much of biodi- recent study by biologist David Pimentel and the myriad effects of climate change.13 versity’s services, however, never trade in and colleagues, biodiversity contributes remains . . . around 50 the marketplace. Still we know they are annually about $2.9 trillion in goods and 18 18 valuable. Some—for example, the genera- services to global human welfare. Population Action International Can Biodiversity Be Perhaps a more instructive way to percent of all species tion of our atmosphere’s oxygen, the Regained? purification of water, the pollination of ask the thorny question—What is biodi- crops, the formation of organic soil com- versity worth?—is to imagine that are projected to Despite the apparent fragility of individual species, fossil evidence also demonstrates ponents, and the cycling of soil nutri- nature’s business is mediated by a that life itself is an extremely robust and ents—are essential to human life and group of environmental trustees. For a survive. resilient feature of our planet’s surface. seemingly irreplaceable on a large scale.15 price, the trustees dispense biodiversi- Even as prior mass extinctions wiped out Another, even less tangible category ty’s services, and with their returns they millions of species, it opened new opportu- includes biodiversity’s aesthetic contribu- maintain and invest to promote those 19 nities for the survivors. Exposed to less tions to the human experience, and its services. How much could they charge? vigorous competition and predation, sur- role as an essential ingredient in the qual- And which aspects of nature would we vivors proliferated and speciated (evolved ity of life.16 willingly pay to maintain and protect? to form new species), filling the gaps left Some economists have argued bluntly For which would we settle for poor sub- by the extinct. that to save a reasonable portion of biodi- stitutes, and which might we let slip Can we rely on evolution to recover versity, society will have to come up with away forever, never knowing their value from the present extinction? Evidence from ways to make the value of nature’s to our descendants? These will be criti- the geologic record tells us that full recovery amenities explicit, or simply risk losing cal questions for coming human genera- from past mass extinctions—recouping not them all. This school of ecological eco- tions. Relating Habitat Area to Species Numbers FIGURE 4 Species Numbers and Habitat Area ost projections of future extinctions scarcity and species numbers, overlooking are derived from trends of habitat the fact that breeding populations are 100% loss. Over decades of field research, being eliminated at all stages of habitat M 90% ecologists have shown that the relationship loss. Losing breeding populations whittles

SPECIES LOSS 80% between habitat loss and eventual decline away at species’ genetic variability and The two lines represent in species numbers, for most groups of their capacity for survival.1 Neither does the lower and upper ranges of species loss 70% organisms, follows a distinct pattern. [See the species–area relationship adequately for various species as habitat declines. Appendix 1c for the equation describing the capture the importance of habitat inter- 60% relationship.] Presently, many ecologists connectedness and habitat quality. As a believe that, if present rates of deforesta- rule, habitats that are fragmented—broken 50% tion and wetland drainage continue, only into small pieces with barriers to move- 40% between 5 and 10 percent of all species-rich ment in between—can maintain fewer habitats is likely to be saved. From the species, while large interconnected habi- 30% IUCN YEAR 2000 SPECIES REMAINING graphed relationship between species and tats in good condition can be expected to GOAL FOR 20% habitat area, it is possible to deduce that retain several more species than the curve PROTECTED AREA losing 90 percent of habitat would likely might predict. 10% result in a loss of around 50 percent of the In 1992, national delegates to IUCN’s 0% original species. | | | | | | | | | | | Fourth World Congress on National Parks 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% 19 Besides their value in predicting biodi- and Protected Areas agreed to a non-bind- Nature’s Place versity loss, species-area curves—as they are ing goal of protecting 10 percent of each HABITAT REMAINING called—tell an important story about extinc- major habitat type by the year 2000.2 As habitat declines greater proportions of species living within those habitats tion. The curve [see figure] predicts that as While some countries have taken this goal tend to become extinct. Research over three decades has shown species-area curves to be reliable predictors of declines in species numbers when habitat area the first bits of original habitat are lost, seriously, still less than one-third have is lost. The curves for most groups of species that have been studied tend to pass species disappear slowly. The first to drop protected 10 percent of their land surface.3 through the region in the graph bounded by the two blue lines. For example, out are the habitat specialists—species with Currently, experts consider saving 10 per- when only 10 percent of the original habitat remains (vertical line), scientists very specific habitat requirements and just a cent of each habitat type to be an opti- expect between 45 percent to 70 percent of the species to remain. And while IUCN’s goal to help secure protection for 10 percent of each natural ecosystem is few breeding populations. Even more rapid mistic expectation, and yet far less habitat laudable, it is clear that meeting this benchmark will not be enough to avoid sig- species loss, however, occurs after habitat than is needed.4 nificant losses of native species. Source: Adapted from A.P. Dobson, 1996. area has been reduced to its last 25 percent. Most ecologists would want to save at By then most species are vulnerable, having least 25 percent of each major habitat dwindled to just a few breeding populations. type. And that hope has nearly been real- References Further shrinkage of habitat tends to result, ized in Costa Rica, where government looks 1. J.B. Hughes and others, Science 278 (1997): 689-692. eventually, in dramatic losses of species. toward the country’s innate biological rich- 2. IUCN, IUCN Bulletin 23, 2 (1992): 10-11. 3. World Conservation Monitoring Centre, in World Resources, 1998-99 Using the species–area relationship also ness both as a valuable economic resource (Washington, DC: World Resources Institute, 1998), Table 14.1. has its drawbacks. For example, it focuses and as an important aspect of national 4. S.L. Pimm and others, Science 269 (1995): 347-350; E.O. Wilson, The policymakers’ attentions narrowly on habitat identity. Diversity of Life (Cambridge: Harvard Univ. Press, 1992). Squandering the Red Queen’s Dowry

lant life has provided modern medicine with some of its most important pharmaceutical products. More than half of today’s prescription drugs are synthesized products modeled on naturally occurring compounds. In the United States, one-quarter of Pall prescriptions contains active ingredients obtained directly from plants, or chemically modified from plant compounds. By the mid-1980s, the annual commercial trade in plant-derived drugs exceeded $40 billion worldwide.1 In terms of human welfare, the potential value of plant diversity is incalculable. For example, several decades ago researchers identified two valuable alkaloids in the Madagascar periwinkle that suppress white blood cell production in humans. One, vinblas- tine, is used in treating Hodgkin’s disease, the other, vincristine, in treating childhood leukemia.2 Unfortunately, we are evidently losing other life-saving medicinal plants before they have been catalogued and assayed. According to the IUCN, almost 34,000 out of an estimated 270,000 known species of vascular plants are threatened with global extinction. The proportion of threatened plant species is even higher in the United States, where almost three in ten of the coun- try’s 16,000 plant species risk extinction.3 The growth of human population, its mobility, and the nature and intensity of its activ- ities are major factors in this risk. It is no coincidence that plants hold so many compounds of therapeutic value to our own species. Humanity has simply appro- priated chemicals from a genetically distant group of organisms, species whose immune systems are the products of successive adaptations to disease after disease over many millions of years. Biologists expect to find these cumulative effects. Their presence is consistent with the Red Queen hypothesis,4 an accepted 20 evolutionary theory named after a character in Lewis Carroll’s Through the Looking Glass. In the Red Queen’s world “it takes all the 5

Population Action International running you can do, to keep in the same place.” Similarly, in order simply to maintain their competitiveness in ecological commu- nities, plant species have evolved and accumulated chemical defenses to ward off attacks by bacteria, viruses and a range of other pathogens, parasites and predators—which themselves keep evolving, too, as if locked into a deadly biochemical arms race. Plant chemical diversity—the Red Queen’s dowry—is precious. But the repercussions of unprecedented growth and mobility of human populations have already narrowed plant genetic variability dramatically. Paradoxically, these same two human population variables—growth and mobility—are known to promote the transmission of emerging infectious diseases.6 We appear to be squan- dering the Red Queen’s dowry, at a time when we need it most.

References 1. P.P. Principe, in Economic and Medicinal Plant Research, ed. H. Wagner and others, Vol. 3 (London: Academic Press, 1989), 1-17; C. Suplee, “1 in 8 Plants in Global Study Threatened: 20-year Project Warns of Major Diversity Loss,” The Washington Post, April 9, 1998, A8. 2. J. Tuxhill, World Watch Paper, 141 (Washington, DC: Worldwatch Institute, 1998). 3. IUCN Red List of Threatened Plants (Gland: IUCN, 1998). 4. L. Van Valen, Evolutionary Theory 1 (1973): 1-30. 5. L. Carroll, Lewis Carroll’s Through the Looking Glass, and What Alice Found There (Berkeley: Univ. of California, 1983; first published in 1872). 6. S.J. Olshansky and others, Population Bulletin 52, 2 (1997). References 1. P.M. Vitousek, “Biological Invasions and M.L. Reaka-Kudla, D.E. Wilson, and E.O. and A.H. Ehrlich, Extinction: the Causes Ecosystem Properties: Can Species Make a Wilson (Washington, DC: Joseph Henry and Consequences of the Disappearance of Difference,” in Ecology of Biological Invasions Press, 1997), 41-68. Species (New York: Random House, 1981); of North America and Hawaii, ed. H.A. 8. D.M. Raup, “Extinction: Bad Genes or Bad G.C. Daily, ed. Nature’s Services: Societal Mooney and J.A. Drake (New York: Springer- Luck?,” New Scientist 14, Sept. (1991): 46-49. Dependence on Natural Ecosystems Verlag, 1986); Office of Technology 9. M.L. Reaka-Kudla, “The Global Biodiversity (Washington, DC: Island Press, 1997). Assessment, “Harmful Non-Indigenous of Coral Reefs: A Comparison With Rain 16. R. Leakey and R. Lewin, The Sixth Species in the United States,” OTA-F-565 Forests,” in Biodiversity II: Understanding Extinction (New York: Doubleday, 1995); (Washington, DC: U.S. Congress, 1993). and Protecting Our Biological Resources, 1997, E.O. Wilson, Biophilia (Cambridge: 2. D. Pimentel, L. Lach, R. Zuniga, and D. 83-108, p. 88. Harvard Univ. Press, 1986). Morrison, “Environmental and Economic 10. T.E. Lovejoy, “Biodiversity: What Is It?,” in 17. H.E. Daly and J.B. Cobb, For the Common Costs Associated with Non-indigenous Biodiversity II: Understanding and Protecting Good: Redirecting the Economy Toward Species in the United States,” Paper at the Our Biological Resources, 1997, 7-14. Community, the Environment and a American Association for the Advancement of 11. S.L. Pimm, G.J. Russell, J.L. Gittleman, and Sustainable Future (Boston: Beacon Press, Science Annual Meeting, Anaheim, CA, Jan. T.M. Brooks, “The Future of Biodiversity,” 1989), p. 204. 24, 1999. Science 269 (1995): 347-350. 18. D. Pimentel and others, “Economic and 3. S.L. Pimm, The Balance of Nature? Ecological 12. N. Myers, The Sinking Ark: A New Look at Environmental Benefits of Biodiversity,” Issues in the Conservation of Species and the Problem of Disappearing Species (New Bioscience 47, 11 (1997): 747-757. Communities (Chicago: Univ. of Chicago York: Pergamon, 1979); W.V. Reid, “Tropical 19. R.U. Ayres, “The Price-Value Paradox,” Press, 1991); D. Tilman and S. Pacala, “The Deforestation and Species Extinction,” in Ecological Economics 25, 1 (1998): 17-19. Maintenance of Species Richness in Plant How Many Species Will There Be?, ed. T.C. Communities,” in Species Diversity in Whitmore and J.A. Sayer (London: Chapman Ecological Communities, ed. R.E. Ricklefs and & Hall, 1992), 55-73; P.H. Raven, “Our D. Schluter (Chicago: Univ. of Chicago Press, Diminishing Tropical Forests,” in Biodiversity, 1993), 13-25; D. Tilman, “Biodiversity: ed. E.O. Wilson and F.M. Peters 21 Population Versus Ecosystem Stability,” (Washington, DC: National Academy Press, Ecology 77 (1996): 350-363. 1988), 119-122. Nature’s Place 4. M. Williamson, Biological Invasions (London: 13. P.H. Raven, “The Politics of Preserving Chapman and Hall, 1996). Biodiversity,” BioScience 40, 10 (1990): 769- 5. C. Bright, Life Out of Bounds: Bioinvasion in 774. a Borderless World (Washington, DC: 14. N. Myers, “The Biodiversity Crisis and the Worldwatch, 1998). Future of Evolution,” The Environmentalist 6. K.G. Gaston and L.A. Mound, “Taxonomy, 16 (1996): 37-47; E.O. Wilson, The Diversity Hypothesis Testing and the Biodiversity of Life (Cambridge: Harvard Univ. Press, Crisis,” Philosophical Transactions of the 1992), p. 330. Royal Society of London, B 251 (1993): 139- 15. R. Costanza and others, “The Value of the 142. World’s Ecosystem Services and Natural 7. N.E. Stork, “How Many Species Are There?,” Capital,” Nature 387, 15 May (1997): 253- Biodiversity Conservation 2 (1993): 215-232; 259; T.E. Lovejoy and G.M. Milne, “Genetic R.M. May, “How Many Species are There on Resources, National Interests and Security,” Earth?,” Science 241 (1988): 1441-1449; P.M. in Environmental Change and Security Hammond, “Species Inventory,” in Global Project, no. 3, ed. P.J. Simmons (Washington, Biodiversity: Status of the Earth’s Living DC: Woodrow Wilson Center, 1997), 174-179; Resources, ed. B. Groombridge (London: D.I. Stern, “Limits to Substitution and Chapman and Hall, 1992), 17-39; N.E. Stork, Irreversibility in Production and “Measuring Global Biodiversity and Its Consumption: A Neoclassical Interpretation Decline,” in Biodiversity II: Understanding of Ecological Economics,” Ecological and Protecting Our Biological Resources, ed. Economics 21 (1997): 197-215; P.R. Ehrlich Banking on Genes to Feed the Future

y the year 2030, the United Nations projects that world population will More of these plants contain useful have grown beyond its present numbers by anywhere from 1.4 billion to traits than geneticists had previously B2.8 billion human beings. Even at the low end of this range, the increase expected. For example, introduction of in food demand over the next three decades will be unprecedented in human genes to commercial tomatoes from a tiny history, the more so if much-needed progress is made to reduce the malnutri- wild relative with small off-colored fruits tion that now weakens some 800 million human beings. increased yield by nearly 50 percent while While there is still potential to expand cropland in a few places in the improving nutritional qualities and even world, agricultural experts agree that the vast majority of fruit color. In China, crop yields jumped by humanity’s future sustenance will be harvest- almost a sixth after low-yielding wild rela- ed from essentially today’s cropland. tives were cross-bred with farm varieties. Yet in the last decade or so, crop Recent research suggests that about half yields have leveled off for the of the most valuable hidden genes can chief commercial grains, only be found among the particular wild despite huge increases in species in which they were discovered.2 fertilizer use worldwide, Once common in the ancient centers of especially in developing crop origin and production [see figure], countries. Efforts in genetic these potentially valuable wild relations of 22 improvement of crops, despite common crop plants are now threatened by

Population Action International the hazards and controversy sur- heavy grazing, rapid urbanization, wetland rounding them, may be among the drainage, deforestation and mechanized Po pula agriculture itself. All of these are charac- tion few options available that help farmers Action International keep pace with the growth of food demand. teristic of human-dominated ecosystems Much of the pressure will be on crop breeders—“gene-shufflers” who cross- that have grown in extent and intensity breed and inbreed plants in search of novel combinations that could substan- along with increases in human population tially boost crop performance. For many crops, however, the genetic deck is and in per capita consumption. missing key cards. For example, North American staple crops like hard red win- ter wheat, which descends from just two Eastern European varieties, and soy- References beans, the offspring of a dozen Chinese strains, offer little prospect on their 1. N.I. Vavilov, Chronica Botanica 13, 1/6 own for genetic improvement. And genetic uniformity increases their vulnerabil- (1949/50); N.W. Simmonds, Principles of Crop ity to pest outbreaks and to emerging diseases. Improvement (New York: Longman, 1979); N. Myers, The Wild Supermarket: the Importance of Where are good genes when you need them? For crop breeders, the newest Biological Diversity to Food Security (Gland: sources of genetic creativity, it turns out, are the old sources—DNA banked in World-Wide Fund for Nature, 1990). the cells of wild ancestral species of crops and in their close relatives, and 2. S.D. Tanksley and S.R. McCouch, Science 277 among remaining crop varieties cultivated by indigenous peoples.1 (1997): 1063-1065. FIGURE 5 Centers of Crop and Livestock Origin Central Asia East Asia Almond Garlic Buckwheat Radish Apple Onion Chive Soybean Carrot Rhubarb Foxtail millet Sweet orange Common grape Spinach Ginseng Tea Cucumber Litchi Turnip Mulberry Water chestnut EUROPEAN SIBERIAN REGION Peach Cattle Lettuce Chicory Licorice Gooseberry Pear North America Kale Watercress Cranberry Jerusalem artichoke Mediterranean Muscadine grape Sunflower Asparagus Globe artichoke Broad bean Mint Cabbage Oat Mexico/Central America Cauliflower Parsnip Avocado Sweet potato Celery Sugar beet Common bean Tomato Common grape Maize/Corn Tabasco pepper Papaya Vanilla BELGIUM Pecan Brussel sprout 23 CARIBBEAN NORTH AFRICA Grapefruit Nature’s Place Cattle Marjoram

Southeast Asia Near East Apricot Indian almond Andes/South America Alfalfa Pea Banana Lemon Cashew Manioc Barley Pig Cinnamon & Mung bean Cayenne Pepper Cabbage Plum Horn of Africa India/Indo-Malaya Cassia Sugar cane Cocoa Pineapple Eincorn Wheat Rye Clove Tangerine Groundnut/ Potato Fig Shallot Black-eye pea Finger millet Black pepper Lime Coconut palm peanut Pumpkin Goat Sheep Bread wheat Mustard Breadfruit Mango Eggplant Lima bean Hazelnut Spelt wheat Castor bean Okra Cardamon Moth bean Leek Sugar beet Coffee Pearl millet Chicken Rice Lentil Sweet cherry Cowpea Sorghum Chickpea Safflower Date palm Yam Citron Sesame Dwarf wheat

The potential hidden among wild gene pools and crop varieties used in subsistence farming first came to scientific attention through the work of Russian botanist Nikolai Vavilov in the late 1930s. With his students, Vavilov first mapped the original geo- graphic centers of major domestic crops, a system which now bears his name—the Vavilov centers of crop origin. Most of these centers of origin overlap areas of dense or rapidly growing human population. Source: Adapted from N. Myers, 1990. II. Four Waves of Human Influence

[We] live in a zoologically uman-caused extinction has a long The results of extensive archaeological and history, predating our demographic paleontological research over the past four impoverished world, from which and technological dominion over the decades leave little doubt that prehistoric all the hugest, and fiercest, and earth. There is evidence that human human hunting of large mammals and flight- hunters played a role in extinctions less birds, as well as some early disturbance strangest forms have recently Has far back as 10,000 years ago, and perhaps of habitat and importation of exotic species, disappeared.1 even 50,000 years before the present.2,3 Back have actually shaped most of the world’s then, during the late Pleistocene Epoch, there modern-day communities of species. The may have been only 5 million humans, assemblages of wild animals that children Alfred Russel Wallace, 1876 equipped with primitive technologies—a far learn so quickly to identify are in fact a pro- Naturalist and evolutionary biologist cry from the 6 billion of our species that foundly diminished inheritance, a pale shad- inhabit today’s high-tech world. ow of the far richer fauna that early humanity encountered as it first spread from Africa to the far ends of the globe. 24 Population Action International The First Wave: Losing the Big Ones For nearly a century, scientists believed that climate warming was solely to blame for the Pleistocene extinctions. But by the mid-1960s, paleontologist Paul Martin and colleagues had pieced together enough archaeological and fossil evidence to show convincingly that the demise of populations of large animals (which biologists call megafauna) followed closely the migration of human hunters who, about 12,000 years ago, crossed the Bering Straits from Asia into North America on a land bridge linking the two continents. In just a thousand years, North America

The Great Auk (Pinguinus impennis) in a woodcut by Danish artist Johannes Larsen (1867-1961), based on a stuffed specimen. By 1844 the Great Auk was extinct. FIGURE 6 lost at least 57 species of large 4 Human Colonization and Associated Species Loss mammals —73 percent of all large ani- % mals on the continent. These included 100 • types of horses and camels, giant sloths, 50 • AFRICA glyptodonts (looking like giant armadil- 0 • los), mammoths and mastodons. Their SIBERIA ALASKA remains line the flooring and garbage pits 100 • EUROPE 20,000 y.a. 12,000 y.a. 50,000 5 y.a. of Pleistocene human settlements. 50 • 11,000 y.a. Because these were the largest ani- AUSTRALIA 0 • HAWAII THE mals, they were also slowest to reproduce 1,500 y.a. AMERICAS AFRICA SOLOMONS and mature, and thus needed the longest 100 • 30,000 y.a. recovery periods to survive frequent NORTH FIJI 50 • 3,600 y.a. hunting. And because these species had AMERICA 0 • MADAGASCAR evolved without humans, they may not 1,500 y.a. have become wary in time to survive. 100 • AUSTRALIA 50,000 y.a. NEW ZEALAND MADAGASCAR – Homo sapiens Predators and scavengers—such as dire 50 • y.a. = years ago 1,000 y.a. wolves, lions and an assorted array of NEW ZEALAND carrion feeders—that relied on these graz- 0 • • • • • 100,000 10,000 1,000 100 ing and browsing species for their food dis- YEARS AGO Source: Adapted from J. Diamond, 1992. appeared along with them, in a tumul- Source: P.S. Martin, 1984. tuous re-shuffling of the food chain. When humans crossed into South America, the Large animal species have suffered extinctions that coincide with the presence of modern humans. The left-hand figure shows the percent 25 survival of large animal species on three continents and two large islands. scenario was replayed. About 80 percent Nature’s Place of that continent’s large mammals suc- cumbed to extinction.2 continent some 50,000 years ago had an colorful paintings of large mammals and While some researchers dispute Martin’s even more dramatic impact than did our human hunters—most more than 14,000 megafaunal-overkill hypothesis, holding arrival in the Americas. Australia lost 86 years old, at Vallon-Pont-d’Arc at least on to the climate-change hypothesis as percent of its marsupial mammals, includ- 31,000 years old7—foretell the dawning the probable cause for North American ing several giant kangaroos, as well as of human art and civilization. But for the Pleistocene extinctions, most biologists marsupials resembling rhinoceros, tapirs, great herds that then roamed the today accept that humans played a pivotal and ground sloths, plus a couple monotremes Mediterranean Basin and the Eurasian role in the extinctions. Without the human (egg-laying mammals) and a lizard larger forests and steppes, the paintings fore- influence, this shift to a warmer, more than any alive today. Out of at least 48 shadow the dusk of their existence. arid climate would probably not, by itself, highly varied large land animals, only have caused such ponderous losses to four kangaroo species survive today.6 The Second Wave: biodiversity. These same assemblages of In Eurasia, Pleistocene losses were large animals had survived roughly 27 roughly comparable to those in North Island Bird Extinctions previous ice ages with several warming America. On the walls of caves in north- When the first human visitors to New shifts before and after each one.2 ern Spain and in the Dordogne River val- Zealand landed on its shores about a Homo sapiens’ arrival on the Australian ley of southwestern France, wondrously thousand years ago, they encountered a diverse array of moderate to large-sized flightless or weakly flying bird species winnowing fastest on isolated islands and animal species well-adapted to a variety evolved, and whenever these species were in lakes, the present wave of extinction is of local ecosystems, just as on the conti- restricted to a few breeding populations, running its course throughout the vast nents. There were large grazers and most disappeared within a few centuries continents, on coral reefs and in the great browsers, predators and scavengers. But, after humans arrived on the scene. In the oceans as well. quite unlike the animals of the conti- Pacific Ocean, this occurred on each of There is another difference. Those nents, these creatures were all birds. By nearly 800 smaller islands to the north species extinguished during the first and the time that Captain Cook circumnavi- and east of New Zealand. In fact, archae- second waves of disruption owed their gated New Zealand in 1769, the 50 tribes ologists have yet to uncover fossil evi- demise largely to innate vulnerabilities, that are now collectively called the Maori dence of bird extinction in the South namely to slow reproductive rates, flight- had grown to over 100,000 people, but Pacific during the long period before lessness or their existence in small, isolat- scarcely a trace of the wondrous birds human contact. ed breeding populations. Most of today’s remained. Polynesian settlement alone eventually threatened species were not innately vul- The ongoing third wave of By the mid-19th century, archeolo- led, estimating conservatively, to the nerable, but were made so by human gists in New Zealand were publishing extinction of more than 1,000 oceanic- activity. Only recently were these species human-caused disruption discoveries of bones of several species of island bird species—though estimates go reduced to small, isolated breeding popula- large flightless birds—called moa in as high as 2,000 lost species. Thus, extinc- tions whose reproductive potential is sup- Maori oral tradition—which passed into tion claimed between one and two bird pressed by degraded habitat and pollution— to biodiversity is extinction prior to European settlement.8 species in every ten then alive on Earth.10 and thus assume aspects of the vulnerabili- There were 13 species in all. One is esti- ties exhibited by the large mammals and fundamentally different mated to have grown as large as 250 kilo- island birds that disappeared before them. 26 grams (550 pounds). The Ongoing Third Wave Already IUCN-World Conservation Population Action International from its predecessors. The evidence—over a half million moa After reading of the already staggering Union estimates that about one-quarter of skeletons linked with ancient Maori settle- toll of human-caused extinctions, one all the world’s mammals and more than a ments—has led scientists to conclude that well might wonder, “what group will be tenth of its remaining birds are at a high human hunters pushed the moas to next, and why?” Fair questions, for most risk of extinction. One-fifth of all reptile extinction. The hunters were equipped of the plant and animal species threat- species, a quarter of all amphibians, and as with nothing more than Stone Age hunt- ened with extinction today coexisted with much as 34 percent of all fishes, mostly ing technology and abetted by the wide- humans for tens of thousands of years. freshwater species, are in similar jeopardy. spread disturbance created by the pigs, Many were regularly hunted and harvest- And these proportions refer only to species dogs and rats that they had introduced to ed. And until between 50 and 100 years already described by science. In the less New Zealand. Archaeology suggests that ago, most were surviving in good order. studied taxonomic groupings, IUCN esti- the Maori depended heavily on the moa The ongoing third wave of human- mates that more than 500 insect species, for food, clothing and ritual items. Even caused disruption to biodiversity is funda- 400 crustaceans, and 900 mollusks are moa eggs were blown out and used as mentally different from its predecessors. threatened as well.11 Among plants, about water vessels.9 Today, breeding populations are disappear- an eighth of the world’s flowering species is What happened in New Zealand ing from species of all evolutionary forms on the edge of survival.12 played out as well in various forms on and sizes, from the largest trees to the tini- Moreover, time scales for human- Madagascar and Cyprus, in the Azores est soil microbes. And they are disappear- caused extinction have shortened. Whereas and on the Caribbean islands. Wherever ing from all regions and habitats. Though Pleistocene mammals withstood several The Nature of Islands FIGURE 7 Islands of Nature: Population Growth and the Isolation of Protected Areas

ver since the voyages of Charles UGANDA KENYA 1960 Darwin and Alfred Russel Wallace Eover 150 years ago, islands have fascinated evolutionary biologists, Lake Victoria and for good reasons. Oceanic islands Maasai Mara have been hotbeds of both speciation National Park (the formation of new species) and recent extinction. For example, before the S Serengeti ally arrival of humans some 90 percent of the original National Park Ethels ton plant species and all of the native terrestrial birds of the TANZANIA Hawaiian Islands were endemic—completely unique to these islands, having evolved from just a few species that landed there over the past several million years. Following the original Polynesian settlement, during which pigs and rats were intro- UGANDA 2000 duced, the Hawaiian Islands lost roughly half of their endemic bird species. Since KENYA 1778, when Captain Cook first visited their shores, the islands have lost an additional 18 bird species and the fate of another 12 Hawaiian birds hangs in the balance. Out Lake Population Density Victoria (people per square 27 of the 980 native plants identified in early collections, 84 are now extinct, and 133 kilometer) are represented by less than 100 individuals in the wild.1 Nature’s Place As it turns out, repeated studies of island species, principally of birds, confirm 0–5

that species confined solely to small, isolated islands face high risks of extinction. 5–50 This lesson from island ecology has even greater significance for 21st century conser- vation. Natural habitats, where they exist as reserves and national parks, are now More than 50 TANZANIA mostly small habitat islands, isolated from one another by a sea of human settlement and activity. As farms have intensified, suburbs grown, road networks expanded and Once stopovers for grazing animals migrating through vehicular traffic increased—each related in some large or small way to continued pop- East Africa’s Rift Valley, Tanzania’s Serengeti National Park ulation growth—habitat area has diminished and successful movements of organisms and Kenya’s Maasai Mara have become, over the past 50 between protected habitats has become less and less likely. What were once vulnera- years, isolated by agricultural settlement. Isolation could bilities associated primarily with fragile oceanic island species, are now characteristics increase the vulnerability of wildlife populations to peri- odic drought, promote inbreeding among some species, of numerous species on the continents.2 and intensify interactions between wildlife, agriculture and surrounding people. To maintain the Serengeti’s mix References of plant and animal species under conditions of increas- 1. C. Mlot, Science 269 (1995): 322-323. ing population density will likely demand greater efforts 2. R.H. MacArthur and E.O. Wilson, The Theory of Island Biogeography (Princeton: Princeton Univ. and financial resources. And much of the funding needed Press, 1967), p. 3-4; M.E. Soulé and B.A. Wilcox, eds. Conservation Biology (Sunderland, MA: will probably have to come from abroad. Sinauer, 1978); H. Remmert, ed. Minimum Animal Populations, Ecological Studies, 106 (Berlin: Springer-Verlag, 1994). Source: R.S. Reid and others, 1999. thousand years of hunting, and many trial surface is fully or partially disturbed tural wastes. The toxic microbe Pfiesteria island birds survived several centuries of by agriculture, natural resource use or is just one example. Observed blooming harvests, species now can pass from hardy, construction.14 Humans now claim for in higher than normal marine concentra- viable populations to the threshold of their own use around 40 percent of each tions of nitrogen and phosphorous, extinction in a matter of decades. year’s terrestrial net primary productivi- Pfiesteria has been responsible for mas- The roots of current extinctions actually ty—the total organic material produced by sive fish kills in coastal waterways in the go back 6,000 to 10,000 years, to a time photosynthetic plants on land.15 Nearly United States several times in the when the habits of human hunter-gather- four-fifths of all native forests that covered 1990s.18 . . . the fourth wave of ers were going through change. Pressured our planet at the close of the last ice age Some higher animals have made clever by the upward momentum of its own has been cleared, fragmented, modified or behavioral adjustments. Among these is numbers and a related scarcity of game degraded,16 and half of that cover has the black kite, a Southeast Asian hawk human-caused disruption animals, Homo sapiens turned to domesti- completely disappeared. At least 10 per- and successful urban predator that has cating plant and animal species, gradually cent of the world’s coral reefs are severely become as adept at snatching sandwiches of biodiversity is a wave took to farming and livestock raising, and degraded. Another 30 percent are consid- from lunching students as it is at plucking forged a new relationship with Earth’s ered in a “critical state,” and thus likely to rodents from rooftops. The chimney swift, of proliferation rather ecosystems.13 Using fire and primitive be lost within the next two decades.17 a small insect-eating bird native to North tools, humans learned to purposefully Clearly the additions to human popu- America, today builds its nest on the shape the course of natural events, and lation projected for at least the next half- inner walls of chimneys rather than inside than extinction, involving then, slowly at first, to radically refashion century will require further appropriation the dead, hollowed-out trees that were entire ecosystems—to create what scien- of Earth’s ecosystems. Such growth, cou- once a ubiquitous feature of the northern a small minority of tists now call human-dominated ecosys- pled with expected growth of consump- hardwood forest. And troops of Hanuman 28 tems. Today these ecosystems appear as a tion and further globalization of trade langurs, a South Asian primate, reside in Population Action International species whose success is highly varied set of landscapes, from swid- and much-needed improvements in the train stations and in temples and fre- den farming to dense metropolitan centers, living standards of the world’s poor, is quently migrate with religious pilgrims. each intended to meet the needs and bound to put at further risk much of the Many of the organisms finding such intimately tied to designs of members of our own species, world’s remaining biodiversity. success are not so harmless. A significant generally at the expense of the needs of number are economic pests, such as our own. wild species. weeds, house rodents and crop-eating On top of that, our extraordinary The Fourth Wave: insects. Some spread disease. And others mobility facilitated the transport of exotic Nature Altered directly cause infectious diseases upon plants, animals and diseases, transfiguring Many species will surely survive us. which billions of dollars are spent annual- previously isolated ecosystems. It is these Some are becoming more numerous and ly for control and eradication. Whatever changes—and the limited capacity of even extending their ranges. This is espe- their habits and genetic origins, these today’s species to adapt to them—that are cially true of biologically invading species species are wonders of rapid adaptation, at the crux of recent and pending extinc- transplanted beyond the reach of com- organisms that have become hugely suc- tions. And these changes, though motivat- petitors, predators and diseases that once cessful by integrating themselves into rel- ed by a complex mix of factors, are clearly constrained them. Other species, adapted atively homogenous and nutrient-rich writ large by population growth. to nutrient-rich conditions that were pre- human-dominated ecosystems.19 How far have these trends gone? Well viously rare, are also spreading, thanks to These make up what might be called over 70 percent of Earth’s habitable terres- a profusion of fertile urban and agricul- the fourth wave of human-caused disrup- tion of biodiversity—a wave of prolifera- FIGURE 8 tion rather than extinction, involving a small minority of species whose success Domesticated Demographics: is intimately tied to our own. Among the Growth of Livestock Populations them are a virtual handful of domesticat- ed plants and animals that, according to 600 some biologists, could be considered the 500 biggest evolutionary winners in the race Livestock to keep pace with human-caused global change. 400 The demographic success of domesti- 300 cated species parallels our own [see figure 8]. As our fortunes—and our popula- 200 tions—increase, so do theirs. Along with WEIGHT BODY Human (millions of metric tons) (millions of their numbers, their demands for energy, 100 nutrition, space and waste disposal grow apace. In the United States alone, live- 0 stock produce more than 900 million met- 1960 1965 1970 1975 1980 1985 1990 1995 ric tons of manure every year, over 4.5 YEAR tons of manure for every person. The U.S. Fish and Wildlife Service identifies live- The growth in livestock, shown above by their accumulated body weights, has kept pace with human population growth. Increases in disposable income glob- 29 stock waste as the principal pollutant of ally are likely to step-up growth among these few species, and thus increase 1,785 bodies of water in 39 U.S. states.21 livestock waste discharge and other environmental changes these species pro- Nature’s Place How many other species are accli- mote. mated or have become acclimated to Source: Livestock numbers from FAO-STAT, 1998; other sources and assump- some type of human-dominated ecosys- tions, see Appendix 1d. tem through genetic change or learning? There appear to be no scientifically- determined estimates. For Europe and In tropical rainforests that harbor many these are small organisms that repro- North America, a survey by Population specialized and interdependent organ- duce prolifically, and mutate frequent- Action International of published guide- isms, the number of species likely to ly. Their recent evolutionary accom- books to flowering plants, birds and adjust to fully human-dominated ecosys- plishments—including bacterial resist- mammals suggests that between one tems probably make up a far smaller ance to antibiotics, malarial resistance and two in every 20 of these larger, well- portion of the total number. to quinine-like drugs, and adaptations studied species is now associated with For smaller species, there is much of crop-eating insects to chemical pesti- farmland, suburban areas and other less information. How many fourth-wave cides—have diminished the signifi- human-dominated ecosystems [see organisms are insects and other inverte- cance of many of humanity’s earlier Appendix 1e], although some of these brates? How many are fungi, bacteria, achievements in biochemistry and species are declining because of pesti- viruses and other microbes? If evolution medicine.22 cides and changes in farming methods. has its way, there could be many, for Scientists see no end to this evolu- An Epoch in the Making

he global environmental change the earth went through 10,000 years greatest long-term impact, species extinctions linked to human activity ago was quite literally epoch-making. Geologists define that time as a from the late Pleistocene through the next few centuries may well resemble Tboundary that ended the 2-million-year-long Pleistocene epoch and mass extinctions of the pre-human past—each of which defined the bound- launched the Holocene in which we live today. Within a thousand years of aries of geological epochs.1 the Pleistocene-Holocene boundary, ocean temperatures warmed. Shellfish Indeed, a case could be made that Earth has entered a new epoch. Call on the ocean floor shifted their distribu- it the Anthrocene, a period initiated and defined by Homo sapiens’ unprece- tions. Atmospheric carbon dioxide leveled dented population and its capacity to influence the planet’s global cycles. Beginning of the off at roughly 280 parts per million, where If scientists poke into the planet’s crust thousands or millions of years Anthrocene? The Present Human Influence it remained until the Industrial Revolution. from now, they may be able to identify the opening of the Anthrocene by a Holocene on Global Ecology On land, average temperatures rose by layer of lead, mercury and other relatively rare metals released from buried 11,000 2.3 degrees Celsius. The massive glaciers plastics and the settling smoke particles of fossil fuels. Probing polar ice years ago Most Large Mammals that had spread into the mid-latitudes and and peat bogs, researchers will find trapped air bubbles with unusually Disappear Pleistocene across the continents over the preceding high concentrations of carbon dioxide—now above 360 parts per million Early 40,000 years began to melt away slowly. and rising—along with trace levels of industrial gases that were new to the Hominids

Quaternary Period And as they did, the great majority of large planet when human beings invented them. In the surrounding media, sci- 1.8 million years ago mammals vanished from North and South entists may find particulate ash from tropical forest burning, tilled soil and 2 30 Pliocene America—a process to which humans sure- fertilizers blown from the world’s agricultural regions, and more heavy Grasslands ly contributed.1 metals left by industrial processes hundreds of times above background lev- Population Action International Spread Today it is increasingly obvious that els.3 The plastic detritus of modern civilization could be as sure a marker of Miocene our species is responsible for fundamental human dominance of the earth as the layer of iridium left over from a CENOZOIC ERA CENOZOIC Large Mammalian changes to Earth’s surface that are compa- coating of meteorite dust 65 million years ago is a marker of the passing of Carnivores Evolve rable to those of the Pleistocene-Holocene the dinosaurs. Oligocene transition. In some locations, persistent What will life be like for our descendants, living later in the

Tertiary Period Tertiary soil erosion and the disposal of hazardous Anthrocene? Much will depend on the success of efforts to halt the four and nuclear waste are leaving legacies of major interacting global transitions—human population growth, species ecological change that could persist for extinctions, tropical deforestation, and global atmospheric and climatic Eocene Mammals, Birds million of years. Over the next few millen- change. Each of these epoch-making transitions has accelerated greatly in and Flowering Plants Diversify nia sea level rise wrought by human inten- the last 50 years, less than a human lifetime. There is no way to know how Paleocene sification of the greenhouse effect could far each trend will proceed, but their destinations will depend in large part 65million years ago Dinosaurs and literally reshape the world’s coastlines. on decisions human societies make in the early years of the 21st century. Marine Reptiles Disappear Increases in temperature and shifts in the water cycle could bring new patterns of References vegetation to the world’s landscapes, and 1. E.C. Pielou, After the Ice Age: The Return of Life to Glaciated North America (Chicago: reprogram the paths and volumes of ocean- Univ. of Chicago Press, 1991), pp. 227-228. MESOZOIC ERA MESOZOIC 2. P.A. Mayewski and others, Science 232 (1986): 975-977. Cretaceous Period Cretaceous ic currents. Finally, and perhaps with the 3. W. Shotyk and others, Science 281 (1998): 1635-1640. tionary tit-for-tat. By some estimates, viruses are “a million times more likely to FIGURE 9 mutate” than human cells and can, in Newly Emerging Diseases some cases, produce a thousand copies in about an hour.23 Though less prolific Year of emergence than microbes, insects seem well suited Disease or re-emergence Country for evolution in human-dominated HIV/AIDS 1975 probably Gabon or the Congo ecosystems. For example, researchers in Legionnaires disease 1976 United States London recently identified a new species Cryptosporidiosis 1976 United States of mosquito in the city’s underground Ebola haemorrhagic fever 1976 Dem. Rep. of the Congo transport system. A descendent of an (then Zaire) aboveground species that taps into birds, Hantavirus 1977 Republic of Korea this one obtains blood from the tunnel’s Creutzfeldt-Jakob disease (CJD) 1979 United Kingdom, Canada rodents and train workers.24 In the early 1970s, advances in vac- Human T-cell lymphotropic virus-I 1980 Japan cines suggested to many clinicians that Hepatitis D 1980 Italy the age of infectious disease was over. Escherichia coli O157:H7 1982 United States Since then clinicians have recorded at New variant of CJD least 28 newly recognized diseases— (related to mad cow disease) 1986 United Kingdom HIV/AIDS, hepatitis C, D and E, Ebola Salmonella enteritidis PT-4 1988 United Kingdom and mad cow disease most prominent Hepatitis C 1989 United States among them—and have had to battle 31 Venezuelan haemorrhagic fever 1991 Venezuela dozens of resurgent infectious diseases.25 Nature’s Place Logically, some of the success of parasitic Brazilian haemorrhagic fever 1994 Brazil organisms could be related to amounts of Vibrio cholerae 1992 India accumulated body mass and energy now Human and equine morbillivirus 1994 Australia available in human-dominated ecosys- tems, and the ease at which these organ- Source: Adapted from D. Pimentel and others, 1998; WHO, 1996. isms can travel between distant hosts. According to PAI’s estimates [Appendix 1d], there are roughly 250 mil- lion metric tons of human mass globally, new start and some new directions. use of biological controls will no doubt and well over twice that in livestock. It is Ultimately, massive education and help us deal with emerging crop pests. not unreasonable to suggest that humans, public health campaigns, poverty allevia- But given human population, the preva- and the ecosystems they remake, are tion, new technologies and human behav- lence and neglect of poverty, and upward becoming the principal organizing reality ioral change may help control the diseases trends in consumption and in travel and for organic evolution. Indeed, a half-cen- that have recently emerged and those that trade, we can be sure that the battle of tury of unprecedented human population may be evolving.26 And methods such as “wits versus genes” will continue.27 growth may have helped give evolution a integrated pest management and careful References 1. A.R. Wallace, The Geographical Distribution 12. IUCN, IUCN Red List of Threatened Plants Discussion Paper, 25 (Washington, DC: of Animals, with a Study of the Relations of (Gland, Switzerland: IUCN-World International Food Policy Research Institute, Living and Extinct Faunas as Elucidating Conservation Union, 1998), p. xvii. 1998); N. Myers, “The Biodiversity Crisis and Past Changes of the Earth’s Surface (New 13. E. Boserup, Conditions of Agricultural the Future of Evolution,” The York: Harper, 1876), p. 150. Growth: The Economics of Agrarian Change Environmentalist 16 (1996): 37-47. 2. P.S. Martin, “Prehistoric Overkill: the Global Under Population Pressure (Chicago: Aldine, 23. See review by A.E. Platt, “How Model,” in Quaternary Extinctions: A 1965). Environmental and Social Disruptions Trigger Prehistoric Revolution, ed. P.S. Martin and 14. L. Hannah, D. Lohse, C. Hutchinson, J.L. Disease,” Worldwatch Paper, 129 R.G. Klein (Tucson: Univ. of Arizona Press, Carr, and A. Lankerani, “A Preliminary (Washington, DC: Worldwatch Institute, 1984), 367-403; Inventory of Human Disturbance of World 1996), p. 6; R.M. Henig, A Dancing Matrix: 3. G.G. Miller and others, “Pleistocene Ecosystems,” Ambio 23, 4-5 (1994): 246-250. Voyages Along the Viral Frontier (New York: Extinction of Genyornis newtonii: Human 15. P.M. Vitousek and others, “Human Alfred Knopf, 1993). Impact on Australian Megafauna,” Science Appropriation of the Products of 24. K. Byrne and R.A. Nichols, “Culex pipiens in 283 (1999): 205-206. Photosynthesis,” Bioscience 36, 6 (1986): 368- the London Underground Tunnels: 4. R. Leakey and R. Lewin, The Sixth Extinction 373. Differentiation Between Surface and (New York: Doubleday, 1995), p. 174. 16. D. Bryant, D. Nielsen, and L. Tangley, The Subterranean Populations,” Heredity 80 (in 5. J. Clutton-Brock, Domesticated Animals from Last Frontier Forests: Ecosystems and press). Early Times (Austin: Univ. of Texas Press, Economies on the Edge (Washington, DC: 25. D. Pimentel and others, “Ecology of 1981). World Resources Institute, 1997). Increasing Disease,” Bioscience 48, 10 (1998): 6. P. Murray, “Extinctions Downunder: A 17. C. Wilkinson, “Coral Reefs of the World Are 817-826. Bestiary of Extinct Australian Late Pleistocene Facing Widespread Devastation: Can We 26. S..J. Olshansky, B. Carnes, R.G. Rogers, and Monotremes and Marsupials,” in Quaternary Prevent This Through Sustainable L. Smith, “Infectious Diseases - New and Extinctions: A Prehistoric Revolution, 1984, Management Practices?,” in Proceedings of Ancient Threats to World Health,” Population 600-628. the 7th International Coral Reef Symposium, Bulletin 52, 2. 7. J-M. Chauvet, E. Brunel-Deschamps, and C. 32 Vol. 1 (Guam: Univ. of Guam, 1993), 11-21. 27. J. Lederberg, “Disease,” in Meeting the Hillaire, La Grotte Chauvet (Paris: Seuil, 18. U.S. Geological Survey, “Fish Lesions and Challenges of Population, Environment, and Population Action International 1995). Fish-Kills,” http://chesapeake.usgs.gov/ches- Resources: The Costs of Inaction, 8. C. Darwin, The Origin of Species By Means of bay (last accessed: October 9, 1998). Environmentally Sustainable Development Natural Selection or The Preservation of 19. D. Quammen, “Planet of the Weeds: Tallying Proceedings, 14 (Washington, DC: World Favoured Races in the Struggle for Life (New the Losses of Earth’s Animals and Plants,” Bank, 1995), 25-26. York: New American Library, 1958, first pub- Harper’s, October, 1998, 57-69. lished 1859). 20. World Conservation Monitoring Centre, 9. H.F. James and S.L. Olson, “Flightless Birds,” Biodiversity Data Sourcebook, ed. B. Natural History 92, 9 (1983): 30-40. Groombridge (Cambridge, U.K.: World 10. S.L. Pimm, G.J. Russell, J.L. Gittleman, and Conservation Press, 1994); J. Clutton-Brock, T.M. Brooks, “The Future of Biodiversity,” Domesticated Animals from Early Times Science 269 (1995): 347-350; D.W. Steadman, (Austin: Univ. of Texas Press, 1981); R. Loftus “Human-Caused Extinction in Birds,” in and B. Scherf, eds. World Watch List for Biodiversity II: Understanding and Protecting Domestic Animal Diversity (Rome: FAO, Our Biological Resources, ed. M.L. Reaka- 1993). Kudla, D.E. Wilson, and E.O. Wilson 21. Scripps Howard News Service, “Is Manure (Washington, DC: Joseph Henry Press, 1997), Laying Waste to Our Soil?,” Sunday, May 10, 139-161. 1998. 11. IUCN, IUCN Red List of Threatened Animals 22. M. Yudelman, A. Ratta, and D. Nygaard, (Gland, Switzerland: IUCN-World “Pest Management and Food Production,” Conservation Union, 1996), p. intro 24. Food, Agriculture, and the Environment III.III. NatureNature Replaced:Replaced: Prospects Prospects forfor OurOur SpeciesSpecies

. . . the world’s nations by s the second millennium draws to size, the large and rapidly growing popula- a close, roughly 6 billion people tion, and the global distribution of Homo their actions or inactions are alive on the planet. The num- sapiens. Nor has any species evolved such will choose from among a ber is unprecedented and impos- intelligence and a capacity for innovation ing, but hard to place in perspec- comparable to our own. There are, in fact, no range of alternative demo- Ative. No other species in the planet’s past models to guide our course. Yet we have graphic futures.1 or present has combined the large body plenty of demographic statistics to consider.

Programme of Action of the 1994 International Conference on FIGURE 10 33

Population and Development Population Growth in the Species-Rich Tropics Nature’s Place Approved by 179 nations Since 1950, human popu- 6 • Cairo, 1994 lation has more than tripled in the tropics, home to probably two- 5 • thirds of Earth’s biodiver- sity. During the same 4 • period, the tropical share of world population grew 3 • from 28 percent to 36

percent and by 1995 (billions) 2 • Other Regions

comprised over 2 billion POPULATION people. Today human population is growing by 1 • around 78 million people Tropics annually. Population 0 • Action International esti- • • • • • • • • • • mates that 51 percent of 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 this growth now occurs Wo rld in the band between the Source: Estimates by Population Action International. Ne igh bors two tropics. [See Appendix 1i.] In comparison to the recent past, Pre-agricultural human diets, however, fell today’s world population is large indeed. in between carnivorous and herbivorous Our species’ numbers have multiplied diets. A liberal estimate of the average nearly 4 times since the beginning of this population density our species would like- FIGURE 11 century, when the world’s population ly have maintained without agriculture is Expected Population Densities of Mammals was around 1.6 billion, and it has dou- around 1.0 to 1.5 individuals per square 10• bled since 1960. These figures are impres- kilometer, similar to the average density at Herbivores sive, yet they still fail to illuminate how which hunter-gatherers lived until relative- we compare as a species to the rest of life ly recently. Compare this with modern on Earth. There is, however, a scientific densities, such as that of Bangladesh with method based on animal body size that over 880 people per square kilometer, and 8• provides some biological perspective to the Netherlands averaging 384 people per human numbers. square kilometer.4 If, on this principle, pre-agricultural humans at densities around 1.0 to 1.5 6• Population From An persons per square kilometer were to Expected Population Ecological Perspective exploit every corner of Earth’s habit- Density of Pre-agricultural People Recognizing that species with larger body able terrestrial surface (about 130 mil- sizes have greater nutritional requirements lion square kilometers),5 the world 4• and therefore must range farther for food, would conceivably support around 130 (individuals per sq. km.) the late Canadian ecologist Robert Henry million to 200 million pre-agricultural

34 DENSITY POPULATION Peters compared species’ average body people. According to several estimates, Population Action International sizes to their documented abundance. For world population surpassed 130 million 2• mammals, Peters found statistical relation- in the early years of the Roman Empire Carnivores ships that predicted numbers of carnivores (before 400 BC), and reached twice that (meat-eaters) and herbivores (plant-eaters) population, or two people per square in natural ecosystems [see Appendix 1d].2 kilometer, around AD 200.6 The United

0•• • • These relationships can be used to esti- States alone surpassed 130 million just 10 • 100 1000 mate how many humans would have sur- prior to World War II,7 and by mid-1999 65 vived if we had remained, in effect, just AVERAGE BODY WEIGHT claimed over 270 million inhabitants. (kilograms) another primate—a species that lived by Even some scientists in the biological gathering seeds, tubers and fruits, and disciplines are unaware of how ecologi- Standard curves predict the densities at which mammalian hunting or scavenging meat, without the cally unprecedented the scale of human herbivores (leaf-eaters) and mammalian carnivores (meat- benefits of agriculture.3 numbers is—not just present numbers, eaters) of different body weights can live in undisturbed habitats. According to the United Nations, in 1999 humans Peters’ equations predict 0.12 individu- but those of the last two millennia as averaged about 44 people per square kilometer, substan- als per square kilometer for a carnivorous well. No other mammal of comparable tially above these curves. Such unusually high density, mammal the size of modern Homo body weight has ever attained anywhere over 30 times what is predicted for a mammal of our size sapiens, averaging roughly 65 kilograms near such abundance, nor has any other with a mixed diet, would not be possible without modern agriculture. (142 pounds), and 2.1 per square kilome- similar-sized terrestrial animal demon- Source: Relationships from R.M. Peters, 1983. ter for a herbivore of the same weight. strated such reproductive success. The range of one to two people per square kilometer has added significance. It FIGURE 12 reflects how dense human populations can Human Fertility Change in the Highly Biodiverse Countries get, on average, before our species must Total Fertility Rate modify the ecosystems we inhabit for our (average number of births per woman) own survival. And it suggests how dramat- 1960 - 1965 1995 - 2000 ically we must now control our competi- Australia 3.3 1.8 tors, predators and parasites, in order to Brazil 6.2 2.3 maintain our numbers. It is these modifica- tions and controls, writ large by the scale China 5.7 1.8 our populations and economies have Colombia 6.8 2.8 achieved, that now pose the principal Democratic Republic of the Congo threat to biological diversity. (formerly Zaire) 6.0 6.4 Ecuador 6.7 3.1 The Reproductive Revolution India 5.8 3.1 Indonesia 5.4 2.6 Today, despite our still growing population, we find ourselves somewhere in the middle Madagascar 6.6 5.4 of a revolution in reproductive behavior. On Malaysia 6.7 3.6 average, family size has decreased by roughly Mexico 6.8 2.8 half, from more than six children per woman Papua New Guinea 6.3 4.6 35 in many countries to fewer than three today. Peru 6.9 3.0

And contraceptive technologies are becoming Nature’s Place Philippines 6.6 3.6 more accessible, more affordable and more South Africa 6.5 3.3 widely accepted. Gaps in access to family planning services and information, nonethe- United States 3.3 2.0 less, continue to exist in many parts of the Venezuela 6.7 3.0 world, especially in developing countries in sub-Saharan Africa, South Asia, and parts of Latin America and the Middle East.8 Recent The countries listed are 18 selected by Conservation International as surveys suggest that even in the United States, megadiversity countries. These countries are home to an inordinately large nearly half of pregnancies are mistimed or share of biodiversity, probably between 60 percent and 70 percent of the global total, including terrestrial, marine and freshwater species. In several unwanted. In the world as a whole, nearly of these countries fertility has declined dramatically over the past 30 years. two out of every five pregnancies are Others remain considerably above replacement-level fertility, which is slight- unplanned, suggesting the impact that ly above an average of 2 children per woman of reproductive age in popula- improved access to safe and effective family tions where there is relatively low infant and child mortality. planning services could have on population Source: Data from UN Population Division, 1998. growth, not to mention on the well-being of women and their families.9 Shifts occurring in women’s roles, access Bordering on Uncertainty: Considering the UN Population Projections

ike other PAI reports, this publication uses the low population pro- fluctuated erratically below 3.5 children jection as a rough semblance of the kind of demographic future we per woman for at least 50 years without L might expect with sound and well-funded population policies around ever having dropped to replacement lev- the world. The high projection, by contrast, may represent a world in which els. In Costa Rica and Chile, fertility governments and leaders have neglected or misapplied the health-related declined rapidly during the 1970s, but and other social strategies stalled at similar levels. that slow population growth For parts of these regions and much of FIGURE 13 and improve human well- the world, predictions of fertility are World Population: Past and Projected being in many other ways. especially difficult. In sub-Saharan Africa

30 The high and low sce- women still bear on average more than narios do not represent mar- five children. In Pakistan, northern India, PAST PROJECTED High Projection 25 gins of error in the conven- much of the Middle East and parts of tional statistical sense. UN Central Asia, women bear around four 20 demographers do not sug- children. For these countries, demogra- gest how probable any pro- phers have few clues as to when further 15 jection is. These low and changes in reproductive behavior and

(billions) women’s roles will occur and how small 36 high scenarios simply repre- 10 future families might be. No indicator

POPULATION sent two distinct but Population Action International extreme sets of assumptions appears in the projections for global 5 Low Projection that UN demographers efforts to change human development policies that would influence population 0 apply, with slight variations, | |||||||||||| to every country. The low growth. Yet it is clear that the size of 1850 1900 1950 2000 2050 2100 2150 variant, in which fertility world population in 2050—whether 7.3 Source: Data from UN Long-Range Projections, 1998. levels off at 1.6 children per billion or 10.6 billion people, or some woman, mimics the path of number in between—will depend in fertility change that has occurred in most of the European countries (includ- large part on the choices that govern- ing Italy, Spain, Norway and Greece) and in several East Asian countries ments, foreign aid donors, businesses (Japan, South Korea, Taiwan and Thailand). In these countries, when fertility and non-governmental organizations dropped from high levels it ultimately dipped below replacement fertility to make in the coming decades. levels of 1.2 to 1.8 children per woman over the last two decades. References The high variant, in which fertility rates are assumed to level off at 2.6 1. C. Haub and N. Yinger, The UN Long-Range children per woman, mimics a number of Central and South American coun- Population Projections: What They Tell Us tries where fertility rates have momentarily stabilized at higher than replace- (Washington, DC: Population Reference ment.1 For example, total fertility rates of both Uruguay and Argentina have Bureau, 1992). to education, and economic and social age necessary, in the absence of net Indonesia, Tunisia, Colombia, Thailand mobility in almost every society are immigration, to replace each generation and Bangladesh—or that Spain and important elements in the transition to with the following one. In the industrial- Italy would eventually experience the lower fertility. Changes in social norms, ized countries fertility rates may well lowest fertility rates in the world. increasing costs and higher expectations remain low for some time, or they could for children, and growing demands on rise again if the tradeoffs and costs of Regional Trends parents’ time, all share in the mix that childrearing decline or if larger families Many of the assumptions for future has increased demand for family plan- regain social approval. Realistically declines in population growth—even ning services. How much and how often speaking, we just don’t know. for the UN high-growth scenario— each has contributed are the subjects of depend on a relatively complete diffu- continuing debate.10 Divergent Futures sion of access to family planning servic- Currently, throughout the developing es and better education for girls in sub- According to the most recent long-range In no small way, the world, women are seeking to have smaller Saharan Africa, in parts of the Middle population projections, by the end of the families than their mothers and even their East, and in northernmost South Asia, 21st century global human population older sisters, and they increasingly have where fertility rates are still high. And survival of many of could reach as high as 16 billion. Or it the means to achieve the family size they there is still considerable uncertainty as could peak at less than 7.5 billion around seek. Several good examples can be to whether declines in fertility will con- 2040 and return again to below 5.5 billion today’s species, large and gleaned from East and Southeast Asia. tinue in Latin America. by the century’s end.14 Between these During the mid-1960s, South Korea, The UN Population Division projects two extreme projections lies a vast array small, is linked to the Taiwan, Singapore, Thailand and former that rising mortality from HIV/AIDS of possible futures, including everything Hong Kong Territory began effective pro- could have significant demographic from continued exponential growth to 37 grams to lower infant and maternal mor- impacts in some sub-Saharan African well-being of the female early stabilization and even eventual Nature’s Place tality, establish easy access to family plan- countries by early in the new century. decline. The outcome of this range of ning services,11 and increase primary Deaths from this virulent disease, most possible population trajectories, now of our own species. school enrollments and educational attain- of which occur among adults in the uncertain, could make a critical difference ment.12 Three decades later, average fertil- prime of their productive lives, could to the prospects for conserving the ity in each of these Asian states is below stall educational progress, decimate the remainder of our biological diversity in two children per woman (the average in able and trained, and set back econom- the coming century and beyond. the United States). Other developing ic development for generations to come. Could there be demographic surpris- countries, including Mexico (2.8 children In the long term, Africa’s HIV pandem- es? Indeed, there already have been sev- per woman), Brazil (2.3), Indonesia (2.8), ic could slow the continent’s eventual eral. During the mid-1970s, annual net Tunisia (2.6) and Sri Lanka (2.1), also are transition to low fertility. With 780 mil- additions in world population actually experiencing downward trends in fertility. lion people today, Africa is projected by decreased temporarily, reflecting devas- Meanwhile, in more than 30 countries in the UN to attain somewhere between tating effects of earlier famine and polit- Africa, women can still expect to bear five 1.5 billion and 2.1 billion people by ical upheaval on the age structure of children or more during their lifetimes.13 mid-21st century, a projection that China’s huge population.15 Few demog- During the late 1960s and ‘70s, nearly accounts for some of the expected AIDS raphers predicted the early declines in all the European countries fell below the mortality. approximately two-child-per-couple aver- fertility in developing countries like enthusiasm for later childbirths and FIGURE 14 Realities and Uncertainties smaller families is opening up the Population in the Industrialized Countries possibility of bringing to an end the Even under the low-growth sce- long history of our species’ popula- 1.50 • • 3.0 nario, human numbers will contin- tion growth. ue to climb for many years, though 1.25 • • 2.5 at a slowing rate. Setting aside the References (births per woman) FERTILITY possibility of catastrophe, most 1. UN International Conference on Population 1.00 • • 2.0 and Development, Programme of Action of (billions) demographers expect that at least the 1994 International Conference on Population Fertility another 1.5 billion people, and Population and Development, 0.75 • • 1.5 probably more, will be added to A/CONF.171/13 (New York: United today’s total of 6 billion before Nations, 1994). 0.50 • • 1.0 growth halts its upward trend. If 2. R.H. Peters, The Ecological Implications of Body Size (New York, Cambridge Univ. POPULATION world population peaks early, con- 0.25 • • 0.5 Press, 1983), pp. 166-167. servation opportunities may arise. 3. R.P. Cincotta and R. Engelman, “Nature While these effects will surely be Displaced: Human Population Trends and 0 •• • • • • •• 0 Projections, and their Meanings,” in Nature 1950 1960 1970 1980 1990 2000 mediated by other economic and technological factors, less competi- and Human Society: the Quest for a YEAR Sustainable World, ed. P.R. Raven and T. tion for land, reduced poverty, less Williams (Washington, DC: National Whereas fertility in industrialized countries is, on average, road-building and less pollution are Academy Press, in press). presently below the level at which couples can replace them- possible outcomes of an earlier- 4. UN Population Division, World Population selves, population continues to grow slowly from population than-expected end to population Prospects: The 1998 Revision (New York: 38 momentum and immigration. Even among these countries— United Nations, 1998).

Population Action International what the United Nations calls the more developed coun- growth that could aid the survival 5. L. Hannah, D. Lohse, C. Hutchinson, J.L. tries—population growth is uneven. Industrialized countries of species by the second half of the Carr, and A. Lankerani, “A Preliminary that have experienced decades of low fertility, such as Latvia, 21st century. In no small way, the Inventory of Human Disturbance of World Portugal and Italy, are now reporting slow declines in popula- survival of many of today’s species, Ecosystems,” Ambio 23 (1994): 246-250. tion. The United States, Australia and New Zealand, however, 6. J-N. Biraben, “Essai sur l’Evolution du continue to add about another 1 percent each year to their large and small, is linked to the Nombre des Hommes,” Population (Paris) populations. well-being of the female of our 34 (1979), 13-25; reprinted in: M. Livi- Source: Data from UN Population Division, 1998. own species. What is exciting Bacci, A Concise History of World Population about the state of the world’s pop- (Cambridge, MA: Blackwell, 1992). 7. U.S. Bureau of the Census, “Census of ulation is not the certainty about Population and Housing,” CPH-2-1 its future direction—there can be (Washington, DC: U.S. Dept. of Commerce, none—but the clarity of its present 1990), Population and Housing Unit trends. At a time of rising concern Counts, Table 16. 8. B. Robey, S.O. Rutstein, and L. Morris, about mass extinctions of wild “Fertility Decline in Developing Countries,” species and the loss of natural Scientific American 269, 6 (1993): 60-67. ecosystems, it can only be good 9. Alan Guttmacher Institute, Sharing news that humanity’s growing Responsibility: Women, Society and Abortions Worldwide (Washington, DC: AGI, 1999). 10. J. Bongaarts and S.C. Watkins, “Social Interactions and Contemporary Fertility Population Momentum Transitions,” Population and Development Review 22, 4 (1996): 639-682; J. Bongaarts, emographers at the United Nations FIGURE 15 “Demographic Consequences of calculate that if average fertility in Understanding Momentum Declining Fertility,” Science 282 India were to have dropped abruptly (1998): 419-420; L. Mazur, High D to replacement-level fertility (slightly Stakes: The United States, Global AGE Population and Our Common above two children per woman) during Males(in years) Females Future (New York: Rockefeller 1995 and had remained precisely at that 80+ Foundation, 1997). level, India’s population, then at 927 mil- 11. A.O. Tsui, “Family Planning 70–74 Programs in Asia: Approaching a lion people, would have continued to grow Half-Century of Effort,” Asia- rapidly, reaching 1.45 billion by 2050.1 60–64 Pacific Population Research This additional growth, occurring after fer- Reports, 8 (Honolulu, HI: East- tility declines to replacement level, is 50–54 45–49 West Center, 1996); Asian years old in caused by population momentum. 1995 Development Bank, Emerging 40–44 Asia: Changes and Challenges Growth due to population momentum (Manila: ADB, 1997). occurs during the decades when a low-fer- 30–34 12. N. Birdsall, B. Bruns, and R.H. Group born tility population with a youthful age struc- 1946–1950 Sabot, “Education in Brazil: ture—a characteristic left over from years Playing a Bad Hand Badly,” in 20–24 Opportunity Foregone, eds. N. of high fertility—gradually fills out to a 10–14 5–9 39 Birdsall and R.H. Sabot more uniform age structure, one that typi- years old (Washington, DC: Inter-American fies a population that is not growing (a in 1955 Nature’s Place Development Bank, 1996), 7-47; 0–4 stationary population). For some rapidly • • • • • • • • World Bank, The East Asian growing countries, this “filling out” could 6 4 2 0 0 2 4 6 Miracle: Economic Growth and JAPAN'S POPULATION Public Policy, ed. L. MacDonald take more than 50 years and double the (in millions) 1955 1995 (London: Oxford Univ. Press, existing population.2 1993). This effect, however, does not mean 13. UN Population Division, World Due to population momentum alone, Japan’s pres- Population Prospects: The 1996 that an extra half-century or more of pop- ent population (gold-colored bars) is about one- Revision (New York: United ulation growth is inevitable in countries third larger than the population it attained almost Nations, 1996). that attain the two-child family average. four decades ago, when it reached the level of 14. UN Population Division, World Momentum is reduced when average fertili- replacement fertility (slightly over 2 children per Population Projections to 2150 woman). Japan’s population is still growing mod- (New York: United Nations, ty falls well below replacement, and when estly today. Demographers at the United Nations 1998). the average age of women at childbirth Population Division, however, project that trend st 15. Committee on Population and rises. to shift during the early 21 century to a slowly Demography, “Rapid Population decreasing population. Change in China, 1952-1982,” References Source: Data from UN Population Division, 1998. Report no. 27 (Washington, DC: 1. UN, World Population Projections to 2150, National Research Council, 1984). 1998. 2. N. Keyfitz, Demography 8, 1 (1970): 71-80. IV.IV. TheThe RoleRole ofof PopulationPopulation GrowthGrowth

The more fundamental causes [of n the late 1970s, American ornithologist ders dried and was soon supplanted by non- Thomas Lovejoy and colleagues began in rainforest plants. Bee populations plummet- biodiversity loss] are rooted in the Brazil a biological experiment planned to ed, even in the 100-hectare plots, placing at contemporary human condition, last a century. Taking advantage of a risk tens of species of orchids and other flow- Brazilian law that required rainforest set- ering plants that depend on them for pollina- especially as they are amplified by Itlers to leave at least half of their deeded land tion. The big mammals with extensive home the explosive growth in human num- forested, Lovejoy convinced several Brazilian ranges and big appetites—jaguars, pumas farmers to leave their rainforest in square and peccaries among them—simply picked bers in the last three centuries.1 tracts of varying sizes, from 1 to 1,000 up and left the area, abandoning even larger hectares (from one-hundredth to 10 square tracts. Without peccaries digging wallows, Michael Soulé, 1991 kilometers). The changes that have so far which fill with rainwater, three species of been documented in the Forest Fragments frogs failed to breed and disappeared. If fun- Conservation Biologist Project provide the most complete evidence to damental ecological theories hold true, fur- 40 date of how human-caused forest fragmenta- ther biodiversity chain reactions can be

Population Action International tion operates on biological diversity. And expected to follow the loss of the big rainfor- while ecologists expect the numbers and est predators. types of species in these habitat fragments to The Forest Fragments Project was continue changing for decades, and perhaps designed with a specific objective: to deter- for centuries, effects were observed within the mine how much rainforest is needed to first several years of the experiment.2,3 maintain 99 percent of native species for a The earliest changes occurred in the small- century. In fact, the project does much more. er forest tracts. In these patches, numerous Considered broadly, the results can help us mid-size plant and animal species dwindled better understand population’s role in biodi- in a matter of years, then disappeared. Closer versity loss—how common patterns of mod- study disclosed that many of the missing ern human settlement and natural resource species were casualties of biodiversity chain use tend to reduce, fragment and isolate nat- Stephanie Koontz reactions. For example, colonies of army ants ural habitat; and how these activities affect a were lost from woodlands of 10 hectares or wide range of species in complex, long-term smaller. Then came the loss of ant-birds, ways, despite our best intentions to save which prey on insects taking flight to escape some portion of nature. marauding ants. Vegetation along forest bor- People and Biological Diversity

15 20 8 14 3 2 19 18 21 25 5 11 B 10 A 16 17 6 C 25 1 4 9 13 23 12 S 7 ou 22 24 rc e: Co ns er Biodiversity Hotspots vat ion Int ern Major Tropical atio nal , 19 Wilderness Areas 99.

The Global Biodiversity Hotspots and Major Tropical Wilderness Areas

Hotspots 10. Eastern Arc Mountains and Coastal 20. Mountains of South-Central China Forests of Tanzania and Kenya 21. Western Ghats and Sri Lanka 1. Tropical Andes From Nature’s Place: Population and 11. Guinean Forests of West Africa 22. Southwest Australia 2. Mesoamerica the Future of Biodiversity. 12. Cape Floristic Province 23. New Caledonia 3. Caribbean Order additional copies from 4. Atlantic Forest Region 13. Succulent Karoo 24. New Zealand [email protected] 5. Chocó-Darién-Western Ecuador 14. Mediterranean Basin 25. Polynesia/Micronesia 15. Caucasus 6. Brazilian Cerrado On the Web at: 16. Sundaland 7. Central Chile Major Tropical Wilderness Areas http://www.populationaction.org/ 17. Wallacea A. Upper Amazonia and Guyana Shield 8. California Floristic Province naturesplace 9. Madagascar and Indian Ocean Islands 18. Philippines B. Congo Basin 19. Indo-Burma C. New Guinea and Melanesian Islands A Upper Amazonia and Guyana Shield 5 Chocó / Darién / Western Ecuador B Congo Basin People and Biological Diversity: Population in the Global Biodiversity Hotspots,1995 1 Tropical Andes 9 Madagascar and Indian Ocean Islands 11 Guinean Forests of West Africa he 25 global biodiversity hotspots, C New Guinea and Melanesian Islands 6 Brazilian Cerrado mapped by ecologist Norman Myers, 2 Mesoamerica Russell Mittermeier and scientists 10 Eastern Arc Mountains and Coastal Forests T 18 Philippines at Conservation International, are consid- 16 Sundaland 23 New Caledonia Population Growth ered to be the most threatened of all bio- 12 Cape Floristic Province of South Africa logically-rich terrestrial regions of the 13 Succulent Karoo in the 17 Wallacea world. Within the hotspot boundaries, 4 Atlantic Forest Region 25 Hotspots and biologists estimate, live at least half of 22 Southwestern Australia Major Tropical 15 19 Indo-Burma the world’s terrestrial species. Recent 20 Mountains of South-Central China Wilderness Areas 21 Western Ghats / Sri Lanka human population growth and migration 20 7 Central Chile 8 Biodiversity Hotspots into these species-rich regions have made 14 14 Mediterranean Basin 25 Polynesia / Micronesia Major Tropical Wilderness Areas biological conservation efforts more 3 Caribbean 3 8 California Floristic Province urgent, more difficult to conduct and 24 New Zealand often more likely to conflict with human 15 Caucasus 18 • • • • • • • • • needs. 2 19 0% 0.5% 1.0% 1.5% 2.0% 2.5% 3.0% 3.5% 4.0% 1.3% per year POPULATION GROWTH As of 1995, more than 1.1 billion people 21 World population (annual rate) 25 growth rate were living in the global biodiversity 5 11 hotspots. While hotspot boundaries B 10 21 Western Ghats / Sri Lanka enclose some 12 percent of the planet’s A 16 17 18 Philippines 3 Caribbean land surface, these biologically diverse 25 C 16 Sundaland 6 14 Mediterranean Basin regions were then home to about 20 per- 1 8 California Floristic Province 11 Guinean Forests of West Africa cent of the world’s human population. All 4 19 Indo-Burma 9 4 Atlantic Forest Region but one of the 25 hotspots are still expe- 15 Caucasus 23 25 Polynesia / Micronesia riencing net population growth. 13 2 Mesoamerica Population Density 17 Wallacea Population Densities By 1995, an additional 75 million people (people per square km.) 10 Eastern Arc Mountains and Coastal Forests in the 7 12 22 5 Chocó / Darién / Western Ecuador were already living within the three major 24 12 Cape Floristic Province of South Africa More than 300 1 Tropical Andes 25 Hotspots and tropical wilderness areas, the last great 7 Central Chile Major Tropical Sou 150 - 300 9 Madagascar and Indian Ocean Islands rce expanses of tropical forest. Population : H 20 Mountains of South-Central China Wilderness Areas ot 50 - 150 spo B Congo Basin growth in these regions has been pro- ts 22 Southwestern Australia from 15 - 50 Con 24 New Zealand ceeding at two and a half times the rate serv 23 New Caledonia Biodiversity Hotspots atio n In 5 - 15 Biodiversity Hotspots 6 Brazilian Cerrado of the world’s population as a whole. If tern ation C New Guinea and Melanesian Islands Major Tropical Wilderness Areas al, 1 1 - 5 999; Major Tropical Wilderness Areas A Upper Amazonia and Guyana Shield present deforestation rates continue popu lation 13 Succulent Karoo density 0 - 1 unabated, these vast native forests could from N • • • • • • • • CGIA/CIE be reduced to a handful of isolated wood- SIN,1995. 0 50 100 150 200 250 300 350 42 people per sq. km. lands in the coming decades. POPULATION DENSITY th World population (people per sq. km.) Population Action International • 1300 19 Steet, N.W. • Second Floor • Washington, D. C. 20036 USA • Telephone: 202-659-1833 • Fax: 202-293-1795 • http://www.populationaction.org density FIGURE ENDEMIC SPECIES The 25 Global Hotspots

Hotspot Hotspot Area sq. km.) (thousands of Human 1995 Population, (thousands) Population 1995 Density, (per sq. km.) Growth Population 1995-2000 Rate, (percent per year) Plants Birds Mammals Reptiles Amphibians Original Extent of Vegetation sq. km.) (thousands of Original Extent Remaining Intact Original Extent Protected 1 Tropical Andes 1,415 57,920 40 2.8 20,000 677 68 218 604 1,258 25% 6.3%

2 Mesoamerica 1,099 61,060 56 2.2 5,000 251 210 391 307 1,155 20% 12.0%

3 Caribbean 264 38,780 136 1.2 7,000 148 49 418 164 264 11% 15.6%

4 Atlantic Forest Region 824 65,050 79 1.7 6,000 73 160 60 253 1,228 8% 2.7%

5 Chocó-Darién-Western Ecuador 134 5,930 44 3.2 2,250 85 60 63 210 261 24% 6.3%

6 Brazilian Cerrado 2,160 14,370 7 2.4 4,400 29 19 24 45 1,783 20% 1.2%

7 Central Chile 320 9,710 29 1.4 1,605 4 9 34 14 300 30% 3.1%

8 California Floristic Province 236 25,360 108 1.2 2,125 8 30 16 17 324 25% 9.7%

9 Madagascar and Indian Ocean Islands 587 15,450 26 2.7 9704 199 84 301 187 594 10% 1.9%

10 Eastern Arc Mts. & Coastal Forests 142 7,070 50 2.2 1,400 22 16 50 33 30 7% 16.9%

11 Guinean Forests of West Africa 660 68,290 104 2.7 2,250 90 45 46 89 1,265 10% 1.6% Population Action International 12 Cape Floristic Province 82 3,480 42 2.0 5,682 6 9 19 19 74 24% 19.0%

13 Succulent Karoo 193 460 3 1.9 1,940 1 4 36 4 112 27% 2.1%

14 Mediterranean Basin 1,556 174,460 111 1.3 13,000 47 46 110 32 2,362 5% 1.8%

15 Caucasus 184 13,940 76 -0.3 1,600 3 32 21 3 500 10% 2.8%

16 Sundaland 1,500 180,490 121 2.1 15,000 139 115 268 179 1,600 8% 5.6%

17 Wallacea 341 18,260 54 1.9 1,500 249 123 122 35 347 15% 5.9%

18 Philippines 293 61,790 198 2.1 5,832 183 111 159 65 301 8% 1.3%

19 Indo-Burma 2,313 224,920 98 1.5 7,000 140 73 201 114 2,060 5% 7.8%

20 Mountains of South-Central China 469 12,830 25 1.5 3,500 36 75 16 51 800 8% 2.1%

21 Western Ghats and Sri Lanka 136 46,810 341 1.4 2,180 40 38 161 116 183 7% 10.4%

22 Southwest Australia 107 1,440 13 1.7 4,331 19 7 50 24 310 11% 10.8%

23 New Caledonia 16 140 8 2.1 2,551 22 6 56 0 19 28% 2.8%

24 New Zealand 260 2,740 11 1.0 1,865 68 3 61 4 271 22% 19.2%

25 Polynesia / Micronesia 46 2,900 58 1.3 3,334 174 9 37 3 46 22% 10.7%

Sources: Conservation International, Population Action International. Linkages in the Literature bance, fragmentation and loss; biological FIGURE 16 The most systematic reviews identify at invasion; pollution; over-hunting and, in a Trends in Extinction least a half-dozen major underlying causes few recent cases, climate change—rather 40 • •7.0 for current declines in species, wild breed- than measures of human population. But 35 • ing populations and natural ecosystems. In there are a few exceptions. In a recent Mammal Extinctions •6.0 each review, population growth—which study, over half of the deaths of African wild Bird Extinctions 30 • can include global and local natural increase dogs were associated with direct human Human Population •5.0 and migration—is listed as one of these contact and infectious diseases obtained 25 • primary root causes.4 from domestic dogs.7 Similar relationships •4.0 It is important to note, however, that could explain wild carnivore declines 20 • 8 •3.0 none of these reviews suggest that the worldwide. And recent research indicates (billions) impacts of human activity on biodiversity that above a human population threshold, 15 • usually between 15 to 20 people per square •2.0 are driven solely by population growth or 10 • by population density alone. It is generally kilometer, elephants move out of certain HUMAN POPULATION accepted that several underlying causes are parts of Zimbabwe. The authors suggest RECORDED EXTINCTIONS 5 • •1.0 at work, some applying pressures that can that this threshold may represent the pat- ? alter ecosystems and deplete species, the terns of farming and natural resource use 0 • • • • • • • • • •0.0 1650 1700 1750 1800 1850 1900 1950 2000 others undermining natural and social means that result from this population density, YEAR that could limit or reverse those changes. rather than elephants’ aversion to human Even in local case studies where researchers numbers per se.9 Though by no means a simple cause and effect relationship, recent analyses conclude that population growth is among a handful of underlying causes of biodiversity loss. found the growth of nearby human popula- Lack of hard evidence for the linkage In the bar graph, bird and mammal extinctions were summed for 50 year periods. The 41

tions to be the most apparent locus of bio- has not deterred scientists from drawing year appearing on the bottom axis is the mid-point of that period. Nature’s Place diversity loss, these same authors consis- conclusions based upon fundamental eco- Source: Data from WCMC, 1992; adapted from graphs by Goudie, 1986. tently indicated that, on close analysis, a logical theories. Several senior ecologists complex mix of interacting conditions and assert that continued rapid population levels of pollution, trends in human-induced failed remedies were involved.5 growth in the tropics is undermining the climate change, and the inroads already How important is population growth and integrity of biodiversity-rich ecosystems, made by invading species.11 population density—the product of past and that present demographic trends bear growth—to current global biodiversity loss? strongly upon what biodiversity will look There is no credible numerical answer to like in the future.10 Yet none of these scien- Links to Direct Causes that question. A recent analysis that relied on tists suggest that population stabilization This section focuses on evidence connect- several measures of root causes (including alone would be sufficient to return extinc- ing human population growth (both glob- population density) to mathematically predict tion rates to background levels. And even al and local) to the direct causes of biodi- proportions of threatened species in over 107 after population stabilization is achieved, versity loss. Connections that are non- countries was only partially successful.6 conservationists will likely face challenges demographic, though very important in Nor does the literature on individual related to the residual state of our human- the overall loss of biodiversity, are not species provide many clues to the linkage. dominated planet, such as: human distribu- given the coverage they would deserve in Understandably, these studies have focused tion and population density, the long-term a more extensive review. After this sec- on the direct causes of decline in breeding viability of remaining species populations, tion, another entitled Considerations populations—the effects of habitat distur- global trends in per capita demand, existing reviews further complexities in the rela- FIGURE 17A tionship between population growth and biodiversi- Causes of Human-Induced Extinction ty loss.

Underlying Causes Direct Causes Habitat Loss and Fragmentation Population Change Habitat Loss and Fragmentation There is consensus among ecologists, with some sup- * Growth * Density * Migration * Deforestation * Large dams * Coral reef destruction porting evidence from research, that habitat distur- * Roadways * Wetland drainage bance, fragmentation (division and isolation of habi- Poverty and Inequity Biological Invasion (Invasive Species and Diseases) tat) and outright habitat loss, taken together, currently * Pressing needs for food and shelter * Competition from invasive species constitute the leading direct cause of extinction.12 * Lack of education * Lack of options * Emerging diseases Habitat loss, the easiest to measure of this composite Policy Failures Pollution category, roughly parallels recent growth of human * Environmentally-destructive subsidies * Synthetic pollutants * Nutrient overloads population. Since 1950, population has tripled and * Poor controls on species trade and movements cropland has doubled in the tropics.13 Today roughly * Lack of environmental awareness Over-Harvesting 97 percent of population growth and over 99 percent * Poor protections for property *Overhunting *Overfishing of agricultural expansion occur in developing regions. *Over-collecting/pet trade Market Failures *Unsustainable logging Several global studies show close associations * Lack of information on species dynamics between population growth and the decline of species- * Lack of information about Human-Induced Climate Change rich tropical forests in developing countries.14 biodiversity’s present and potential value * Shift in geographic range However, these and other studies caution against over- * Susceptibility to diseases ly simplistic explanations of changes in forest cover, Studies tend to separate the causes of biodiversity loss into direct causes, the factors most immediately linked to such as those based upon population growth alone. 42 extinction, and underlying causes which are often called root causes. Generally working in combination, these under- Accordingly, most analysts of localized deforestation in

Population Action International lying causes control the type, frequency and intensity of the more direct causes of biodiversity loss. the tropics describe a complex mix of factors leading to habitat loss. These include various combinations of FIGURE 17B land inequity and patterns of past settlement, local Threats to Species in the United States population growth and migration from growing urban areas and crowded agricultural zones, commercial log- 100% • ging and mining, road-building, settlement schemes, 85% unemployment and poverty, and even political insta- 80% • Despite the increasing threat of species bility and violence.15 invasions and pollution to biodiversity Linkages also exist between population growth and 60% • in the United States, habitat loss and aquatic habitat loss. Jointly, agricultural and housing 49% fragmentation remain the major source sectors account for nearly three-quarters of annual 40% • of threat to imperiled species. Because water withdrawals worldwide, and historically these 24% many species are subject to multiple threats, percentages add up to more 20% • 17% have been major driving forces behind dam building than 100 percent. 16 SPECIES AFFECTED 3% and water diversion. The effects of damming—creat- 0% • Source: D.S. Wilcove and others, 1998. ing barriers to aquatic migration and altering water • • • • • Habitat Alien Pollution Over- Disease dynamics—are, in turn, considered to be among the Loss and Species Exploitation two leading causes (along with biological invasion, see Fragmentation below) of aquatic extinction.17 According to the UN DIRECT CAUSE OF THREAT Commission on Sustainable Development, experience indi- FIGURE 18 cates that “special attention” is required to keep aquatic ecosystems intact in countries withdrawing more than 20 per- Limited Alternatives: Population Growth and Responses cent of their fresh water supplies for annual use.18 Though in Agriculture and Housing data quality is relatively poor for this measure, it is estimated that at least 47 countries presently fit this category.19 Habitat Loss and Fragmentation, Spread of Biological Invasion Invasive Species A recent review of global species decline ranks biological inva- sion (processes by which species become established in ecosys- tems to which they are not native) as the number two cause of global biodiversity loss.17 A study of threatened species in the United States came to a similar conclusion. Despite internation- al agreements and elaborate border controls set up to prevent Cropland Housing biological invasion, the frequency at which invading species Expansion Sprawl are establishing themselves appears to be on the rise. Population growth has probably not been the most critical cause underly- ing biological invasions. Historically, most invasive species have been unleashed deliberately or carelessly by individuals Increased Increased ignorant of the potential for economic harm. Yet population Demand Population Growth Demand for Food for Shelter growth’s effects are nonetheless discernable. Biological surveys of human settlements illustrate this com- 43 plex relationship. Several studies report greater counts of bird Nature’s Place and plant species in parks, along roadsides, and around rural Intensified Farming housing than in comparable forests. Yet high tallies in these Urban (increased fertilizer, Concentration areas can often be explained by the added presence of orna- water use, pesticides, mental and invasive species.20 Port cities tend to act as launch- and livestock waste) points for biological invasion. In San Francisco Bay, for exam- ple, one exotic marine species establishes itself on average, every 12 weeks.21 Denser human settlement means significant shifts in soil chemistry22 and more frequent soil disturbance. Such basic changes can encourage the proliferation of invasive species. Concentrated Pollutants, Population growth expands the scale of trade and transport Changes in Water Cycle and upon which many countries now depend. By 1990, more than Aquatic Ecosystems 1.2 million tourists were arriving in foreign destinations each day.23 Over 86,000 merchant vessels ply the seas, emptying Demand for food and for basic shelter tends to closely parallel human population growth. For a cargo and ballast thousands of miles from their point of origin.24 country to meet these basic needs using its own natural resources, it must experience develop- The daily movements of people, resources and species across ment sprawl or intensification, and most often some combination of the two. Each response can have dramatic consequences for biological diversity. Imports and exports of food also affect the geographic barriers that once isolated them could increase scale of demand. And transportation networks, economic productivity, affluence and public poli- with globalization of trade, population growth, and the inte- cies tend to shape the geographic patterns of housing and urban growth. Places Apart: Military Tensions and Biodiversity

mong the most convincing evidence of population growth’s rela- tionship to biodiversity comes from an unexpected source: a collec- Ation of unintended experiments that are byproducts of late-20th century hostilities and tensions. In the unpopulated Demilitarized Zone that straddles the 250-kilometer border between North and South Korea—no one’s idea of a wildlife refuge—researchers recently discovered several species of animals and plants thought to have disappeared from the Korean peninsula. After 50 years of military standoff, the zone’s biodiversity is now so much richer than the surrounding countryside that Korean and inter- national environmental organizations are working to turn the area into a cross- border national park.1 Similarly, Soviet-Chinese tensions beginning in 1960 discouraged settlement and development in CHINA Wh ite-n aped parts of the Amur-Sakhalin region of Siberia, now the last crane, Sergei Smirenski outpost of some of Russia’s most threatened species, including the Amur tiger, Amur leopard, Blakiston’s fish-owl, and red-crowned and NORTH KOREA white-naped cranes. Several Russian ecologists have raised private Pyongyang Sea of Japan 44 funds and donated their expertise in an effort to protect more than

Population Action International 2 Seoul 200 square kilometers of Siberian forest and wetland in this region. Incheon In the United States, huge military reserves and security zones, SOUTH established around the country’s atomic research laboratories at the KOREA Yellow Sea beginning of the Cold War, have become habitat refuges for threat- ened species that are otherwise rare or absent from the surrounding JAPAN human-dominated landscape. For example, some ecological researchers consider Oak Ridge National Laboratory’s 14,000-hectare reservation to be more pristine than most U.S. national parks. The Nature Conservancy tracks roughly 400 animal species and 11,000 plant species in this area alone.3 Many more of these depopulated areas exist around the world. Turning them permanently into conserva- tion reserves—what conservationists are calling “peace parks”—could provide new hopes for conserving many threatened species and ecosystems.4 References 1. K.C. Kim, Science 278 (1997): 242-243. 2. S.M. Smirenski and J. Harris, “The Amur Program Activity,” Activity Report (Muraviovka, Russia: Muraviovka Park, 1997). 3. K.S. Brown, Science 282 (1998): 616-617. 4. C. Wheal, People and the Planet 7, 4 (1998): 28-30. gration of more of the developing world’s urban and farmland runoff are thought to trucked to nearby urban markets. Some people into the global economy. be responsible for the development of about bushmeat hunting is associated with forest 50 coastal “dead zones,” marine environ- settlers. The more exotic species end up as Pollution ments depleted in oxygen by the mass far away as Europe and Asia. Indigenous Today, the earth’s biosphere is exposed to decay of algae and nearly devoid of other forest peoples, many of whom depend on tens of thousands of chemicals, including sea life. One dead zone near the outlet of wildlife for protein, are either being impov- some 600 pesticides, that were absent dur- the Mississippi River covers 18,000 square erished by the trade or drawn into commer- ing all pre-human evolution.25 For only a kilometers, an area larger than Kuwait.31 cial hunting themselves.34 few hundred of these chemicals do scien- Even larger dead zones are reported in the Growing demand for many marketable tists understand even some of their short- Baltic and Black Sea. species is, in part, linked to population term biological implications. Chemical- Today roughly two-thirds of the world’s growth. For example, Indonesian wildlife intensive agriculture, probably essential at people live within 150 kilometers of coast- managers blame the exotic appetites of current levels of human population,26 is a lines. This proportion is projected to rise to large populations in northern Asian coun- major source of both natural chemical over- three-quarters by year 2025, adding between tries, particularly those with growing pur- loads (particularly nitrogen and phospho- 1.4 and 2.3 billion coastal dwellers world- chasing power, as the principal motivation rus) and synthetic-chemical toxicities in wide in just 25 years.32 The ecological for Indonesia’s bushmeat trade. But on the aquatic and terrestrial ecosystems. In the changes that will accompany such rapid supply side, population appears less impor- United States alone, estimates suggest that and concentrated growth will very likely tant: a few well-organized and well-armed more than 60 million birds are killed annu- pose a major threat to remaining biodiversi- ally by pesticides applied to farmland.27 ty-rich estuaries and coral reefs.33 There is also evidence that nitrogen in rain- 45 fall, now between 10 and 100 times the Over-Harvesting FIGURE 19 Nature’s Place normal rates in North America and Europe, Overhunting, overfishing, overtrapping, More People, More Non-Native Species is upsetting relationships in terrestrial plant and wild plant collecting continue to repre- 28 communities. sent extremely serious threats to many 100% • Where people concentrate in urban and species. This is particularly true when laws suburban areas, so do nitrogen and phos- that restrict and control harvesting are 80% • phorus-containing compounds—in sewage absent, weak or not enforced, and where and organic garbage, in industrial and auto- demand for species is high. Perhaps the 60% • mobile emissions, and in lawn fertilizers. most well documented example of over- Exposed soils on road and housing con- harvesting is collectively called the bush- 40% • struction sites are also significant sources of meat trade, a market that moves weapons INTRODUCED pollutant runoff, as dying soil micro-organ- to forest hunters, and wild animals from PLANT SPECIES 20% • isms release their cell-bound nitrogen into tropical forests to the dinner table. Mammals, 0% • 29 • • • • • • more soluble forms. In a review of 39 of including primates, are the prime targets of 0 5 10 15 20 25 the world’s watersheds, researchers con- bushmeat hunters. But the trade also HOUSING DENSITY cluded that population density is the most includes birds, reptiles and amphibians. (houses per sq. km.) powerful determinant of river-borne nitrates, Bushmeat hunting has been document- An innovative study in Buenos Aires that sampled in rural and urban areas showed that regardless of the size of the watershed or ed in each of the extensive tropical forests. native plant species were replaced by introduced species—both planted exotics and inva- amount of water flow.30 Nutrient-rich Most of the kill feeds logging camps or is sive weeds—as urbanization progressed. Source: Adapted from E.H. Rapaport, 1993. FIGURE 20 poachers can do the job. And economic ing northward as southern populations hardship may make illegal hunting a more disappear, is perhaps the best document- Nitrogen Pollution and Population Density appealing livelihood.35 ed of many cases where global warming 600 • Animal and wild plant-parts also find appears to be influencing species distri- 61 Rivers in developed countries Thames their way into African and South American butions. The threat to biodiversity is Rivers in developing countries 500 • tourist curios, or into South and East not so much climate change itself, which Asian herbal medicines, while much of has occurred numerous times in the past

400 • the exotic pet and plant trades are des- of every living species, but the added Rhine tined for North America. Each illegal inability of animal and plant species to Meuse market poses a formidable threat to par- shift their ranges in response. The unprece- 300 • ticular species—especially primates, col- dented pervasiveness of human settle- orful mollusks and corals, seahorses, and ment, vegetation change, agricultural 200 • Yellow Tiber Mississippi Ganges tropical birds and plants—despite restric- activity, road-building and vehicular traf- (micro-moles of nitrate per liter) nitrate of (micro-moles Yangtze

NITRATE CONCENTRATION NITRATE Hudson tive national and international laws. fic—all showing upward trends, thanks 100 • • • • • • • 0 100 200 300 400 500 In addition, humans are still hunters in part to population growth—precludes POPULATION DENSITY on the world’s waters. The IUCN-World such responses in the foreseeable future. (people per sq. km.) Conservation Union now carries numer- As temperature and weather patterns ous once-commercial fish species on its change, what will happen to those Researchers have found a close relationship between the density of human Red List of threatened species. The south- threatened species now cloistered in pro- population that lives in a watershed, and the amount of nitrates in the water- ern bluefin tuna, the Atlantic halibut, yel- tected areas, and surrounded on all sides shed’s primary river. Source: Data from J.S. Cole and others, 1993. low tail flounder and several species of by agricultural and urban development? 46 shark are among them. In already over- Could reserves be shifted, re-established Population Action International exploited coastal waters throughout the under the right habitat conditions and tropics, desperate fishermen have turned restocked with species? According to one Louisiana Mississippi River to using small-mesh nets, cyanide and recent study, a 3 degree Celsius increase dynamite, thus killing corals and damag- in global average temperature—well with- ing supporting reefs, and pushing hun- in the range of possibilities over the next 50 km dreds of tropical marine fish and inverte- few centuries—could eliminate 7 to 11 brate species towards extinction.36 percent of North America’s vascular plant Humans are also wholesale gatherers species.62 Trends in population growth Bottom dissolved oxygen less than 2.0 mg/L. of the world’s tree species. The IUCN and rapid climate change present a brand In marine dead zones, such as the one (above) that has developed in the concludes that tree felling is the most new set of conservation challenges. Gulf of Mexico, dissolved oxygen in the bottom layer of seawater is present at important impact on tree diversity, and levels below 2.0 milligrams per liter. Development of dead zones—where sea now lists more than 8,700 tree species as life is nearly absent—is associated with the accumulation of large volumes of threatened.37 Considerations nitrogen and phosphorous—containing chemicals that are washed from urban centers, farms and livestock into coastal marine environments in which there The following section highlights the is limited water mixing. Source: Science, 1998. Human-Induced Climate Change complex nature of relationships between A recent census of a butterfly known as population growth and biological diversi- Edith’s checkerspot, whose range is shift- ty. These complexities are principally due to variations among human social and enced by human occupancy in the distant tant to conservationists. Migration into economic systems, and in their capacities and not-so-distant past. and around biologically diverse regions is to transform nature and to respond to threats In general, where such co-existence a critical concern for conservation pro- of biodiversity loss. Each topic discussed occurs today, indigenous people live at grams worldwide.44 And for indigenous below should be an important considera- low levels of technology and in relative groups trying to maintain their cultural tion in policymaking, and worthy of further isolation from the global economy. traditions and customary rights to natural research. Moreover, population densities tend to be resources, the influx of settlers can mean extremely low in these situations, gener- an end to a way of life and a threat to Indigenous People ally less than five people per square kilo- their very existence.45 Recent research casts doubts on notions meter over their full hunting and gather- Migration can be an exceptionally pow- that technologically primitive peoples ever ing ranges. In almost all cases, the sur- erful agent of change, especially when As temperature and lived harmoniously with the full comple- vival of these peoples, their languages, added on top of already high rates of natu- ment of biodiversity that they first encoun- knowledge and practices are just as much ral increase. In the forested Petén region of tered. More likely, Homo sapiens arrived in in jeopardy as the biodiversity with the Yucatan Peninsula, for example, migra- weather patterns change, new lands and hunted the largest and most which they are associated.42 tion has pushed rates of annual popula- easily harvested animal species for food, often Since the late 19th century and tion growth to between 8 and 10 percent, what will happen to those driving the majority of them to extinction.40 throughout the 20th century, there have more than three times the growth rate of That said, there is ample evidence that been numerous cases where indigenous Guatemala as a whole.46 Similarly, immi- threatened species now many human tribal groups settled into peoples were removed or restricted from gration from mainland Ecuador to the various patterns of co-existence with the tribal lands in order to establish national Galapagos Archipelago could double the cloistered in protected remaining, perhaps less vulnerable, plant parks and other protected areas. The wis- islands’ resident population in 7 to 12 and animal species. Some indigenous dom of these displacements has been crit- years.47 47 groups continue such patterns today, often icized. Many might not have occurred had The question is, why now? Why are areas, and surrounded on Nature’s Place holding knowledge that is key to conserv- equitable rights and just compensation the most remote and biologically-rich ing and utilizing the species around them. been extended to these peoples. Current ecosystems experiencing such pressures all sides by agricultural Substantial evidence suggests that some trends in conservation ethics encourage from migration? One answer is, arguably, cultures have actively promoted the abun- biological conservationists to negotiate that these ecosystems are all that remain. and urban development? dance of particular species either by peri- arrangements that respect both cultural For example, few migrants would now be odically burning vegetation to increase and biological diversity, and share the moving into these inhospitable and only game species, by developing sophisticated benefits of conserving species among gov- marginally arable lands if land of greater restraints on hunting, or by adapting forest ernments, local people and private com- potential were not already claimed, or if gardening techniques fostering local native panies.43 jobs were available. And though clearly plant and animal species.41 Patterns of important, population growth is not the impact of these indigenous people often only factor activating human movement. resemble those of occasional natural Migration, Land Inequity and Today’s cumulative distribution of popu- occurrences such as fires and storms, to Population Growth lation—occupying virtually all land of which species have adapted over eons of In the short term, migration and natural prime agricultural potential and packing time. And many landscapes that we label increase in population are easily distin- habitable coastlines—has been greatly “wilderness” have, in fact, been influ- guishable, and the distinctions are impor- influenced by historic and political pat- terns of conquest, colonization, road million people were chronically malnour- by retirement incomes and factors that building, government-subsidized migra- ished. And by one estimate crop intensifi- allow greater separation between homes tion, and, very often, the grossly cation has spared—at least temporarily— and conventional urban workplaces.54 inequitable distribution of land.48 an additional 27 percent of Earth’s habit- The trend raises concerns among wildlife able land surface from conversion to agri- managers, not only because of habitat Agricultural Intensification cultural use.52 Still, intensive agriculture loss, but because of the inevitable growth and Reforestation is not an ecologically benign response to of predatory pet populations and the Studies suggest that in some farming population growth or to shifts in per capi- spread of invasive plant species. areas, particularly those with adequate ta consumption. High concentrations of While industrialized countries current- rainfall or irrigation, the declines in per chemical nutrients and animal wastes, ly account for a disproportionately large capita arable land and increases in land the signature of intensive food-production share of housing, requirements for shelter In a sense, we are value that routinely accompany population systems, have proved difficult to contain in developing countries are projected to 53 growth can act as inducements to intensify safely, even in industrial countries. more than double by the middle of the So far humans have met many of the 21st century.55 This upsurge in housing adapting to ourselves in farming—to apply more labor and tech- nology, to abandon grazing for farming, environmental challenges of unprecedent- needs is projected as a result of popula- and to produce more food per hectare.49 A ed population growth. In a sense, we are tion growth combined with a gradual large numbers, and in recent review of some 70 case studies, all adapting to ourselves in large numbers, shift to fewer people per household. Thus, of them from farming communities in and in some cases we are doing that well. there is a type of housing momentum—a some cases we are mountain areas in developing countries, But will most other species survive our tendency for per capita housing needs to found that these communities are often success in this endeavor? That is a very increase even while population growth sites of environmental restoration, such as different environmental challenge. slows. Today between one-fourth and 48 doing that well. But tree planting and water management.50 one-fifth of all households in the industri- Population Action International The review also points out, however, that Housing Momentum: Trends in alized countries are single-person house- will most other species planting trees and building terraces, though Urbanization and Sprawl holds. A similar trend is expected to critical environmental improvements, are Like food production, housing construc- occur in developing countries as family survive our success? not the same as maintaining native forests tion and home services (water, energy size becomes smaller and economies 56 and their species. Native species and vari- and waste disposal) tend to accommo- industrialize. eties are lost throughout the conversion to date population growth. Patterns of con- farmland and settlement—the most sensi- centration and suburban sprawl vary con- The Population Pressure Transition: tive disappear at the early stages. Agroforestry siderably between countries. Suburban Development and Its Effects on and erosion control (which often employ sprawl tends to consume agricultural land Protected Areas non-native species) were never designed and its water supplies, including any of Governments worldwide have accepted to maintain the full complement of native the habitat that farmland protected. the notion of protected areas—the IUCN species and natural ecosystems.51 Urban concentrations tend to concen- term for parks and reserves, many of In terms of food production, agricul- trate pollutants, dramatically affecting which have the conservation of biological tural intensification has been enormously aquatic and coastal marine ecosystems. diversity as part of their mandate. Over successful. Despite rapid population The United States is experiencing major the past decade, the total amount of ter- growth, malnutrition is down slightly housing construction near environmental- restrial protected area in the world has from a peak around 1970 when over 900 ly pristine areas, a trend probably driven increased by nearly 40 percent, most of it Suburban Predators

here there are people, there are pets. And while house pets bring a great deal of satisfaction to their owners, they are, after all, introduced species. As such, Wtheir numbers and activities can affect biological diversity, particularly when significant numbers roam outdoors. Some ecologists suggest that many of our environmental problems with pets stem from pets’ abilities to thwart some of nature’s most fundamental rules. When prey populations decline in numbers in the wild, so do wild predators—but not popula- tions of cats and dogs, which are protected by feeding and household shelter. Also, predator-pet populations are not as limited by territoriality, as is the case for many wild predators. While several pet species are known to affect native species, the case against poorly managed house cats is perhaps the best documented of all. In the United States, domestic cats (of which there are at least 60 million in U.S. homes and per- haps 30 to 40 million more feral) are estimated to kill over a billion native small mammals and, conservatively, 200 million birds annually.1 To date, domestic cats have been implicated, to varying degrees, in the endangerment of at least six species of North American birds and small mammals, and in the extinction of more than 20 49 2

animal species in Australia. Nature’s Place Diseases common among both dogs and house cats afflict related native preda- tors. African wild dog populations, now numbering fewer than 5,000, are threatened, in part, by rabies and canine distemper, and viral infections transmitted to them pri- marily by domestic dogs.3 Likewise, the viruses causing feline leukemia and feline distemper have spread from domestic cats into populations of North American moun- tain lions.1 Pet population densities respond to both rising human affluence and population growth. How pets have been managed has clearly affected biological diversity, and will likely influence its future in our human-dominated world.

References 1. J.S. Coleman and others, “Cats and Wildlife: A Conservation Dilemma,” Extension Bulletin (Madison: Cooperative Extension Service, Univ. of Wisconsin, 1997). 2. D. Pimentel and others, “Environmental and Economic Costs Associated with Non-indigenous Species in the United States,” (submitted). 3. R. Woodroffe and J.R. Ginsburg, Oryx 33 (1999): 132-142. from increases in the developing world.57 extinction. Because public reserves in living in industrialized countries account Despite these gains, the process is contro- North America and Europe were most for some 86 percent of all private con- versial. Disputes arise over each new or often set up to preserve picturesque land- sumption, and over 80 percent of world expanded protected area, and tensions scape and historic sites or to control trade. In 1998, donor countries provided over use and access often persist for gen- recreational and timber resources, rather only 0.23 percent of their combined gross erations after boundaries are drawn. than to conserve biodiversity, the indus- national product to international develop- In developing countries, pressures trialized countries face large gaps in ment assistance, far short of the United from growing populations have most species protection. For example, recent Nations’ target of 0.7 percent.61 Increasing often been exerted from expanding settle- studies in the U.S. state of Utah led foreign assistance could have major impli- ment within and around the edges of parks researchers to conclude that between 25 cations for the developing world, for social and reserves. The weakest of these and 40 percent of the state’s vegetation as well as environmental programs, includ- Scholars of economic reserves, or “paper parks” as conservation- types are at risk due to a lack of formal ing biodiversity conservation. While ulti- ists call them, lack the funding and political protection.59 Suburban development, mate responsibility for conserving species commitments to deter illegal resource use growing demand for natural resources rests with the countries wherein those history conclude that and species loss. and rising land prices could make future species originally reside, there is currently Population-related pressures on protect- land acquisitions and conservation much more interest in industrialized coun- institutions tend to work ed areas do not necessarily fade away agreements increasingly difficult. tries in saving certain tropical species and with development and enforcement of ecosystems (and more financial resources, best for those who make reserve boundaries. They merely shift. In Global Inequality and Consumption as well) than currently exists in the trop- industrialized countries, impacts are exert- The world’s wealth is unequally distrib- ics themselves. ed at long distances. For example, bound- uted and current trends lean toward 50 their rules—and wild aries of the Everglades National Park and even greater inequalities. Presently, the Institutions: the Rules of the Game Population Action International Audubon’s Rowe Sanctuary on the Platte poorest one-fifth of the world’s popula- For conservation scientists, ongoing species are, of course, not River in the United States are amply pro- tion average less than a dollar of income upward trends in demand for natural tected, yet both reserves have suffered sig- a day and account for less than 2 per- resources forebode a bleak future for making the rules. nificant habitat degradation because of cent of all private consumption.60 How biological diversity. There is good news, irrigation projects and growing urban use industrial countries deal with global however. Demand is not all that counts. upstream. Yearly freshwater flows through development, and how the wealthy and To restrict the flow of natural resources these ecosystems register as a mere frac- educated of each nation deal with the and to control access to them, nations tion of what passed through 150 years poorest segment of their society, will rely on what social scientists call mod- ago—and it was to these past levels that likely have important implications for ern institutions—rules of law, markets native plants and animals originally adapt- the future of biological diversity. Simply and property rights, and government ed. By comparison, many less policed put, species loss can create economic programs and policies. And the success reserves in developing countries are less risks that are chiefly long-term, while or failure of these institutions make it threatened.58 many of the world’s poor face uncertain- difficult to predict precisely how popula- Thus, despite a century of conserva- ties about tomorrow’s meals. Poverty tion growth or changes in per capita tion legislation and litigation in the indus- forces people to take sustenance from consumption will ultimately affect natu- trialized countries, thousands of species the most unprotected of resources. ral resources.62 outside the tropics are threatened with The 20 percent of world population There is bad news, too. Scholars of economic history conclude that institu- Patterns of Loss for temporarily maintaining some tions tend to work best for those who species in off-site facilities like zoos and The bulk of evidence suggests that there make their rules63—and wild species are, germplasm banks, than anywhere within are patterns of biodiversity loss associat- of course, not making the rules. their native range.67 ed with population growth—patterns Government subsidies are a case in point: Population growth is, and has clearly that are repeated and clear, yet neither for example, bringing in the 1994 world been, an important underlying cause of simple nor entirely inalterable. Today, fish catch was estimated to cost $124 bil- recent losses to biological diversity. Just ecosystems populated at low densities lion but was worth only $70 billion at as clearly, it is not the sole culprit, nor vary widely in their conditions. Some dockside. Timber harvests, grazing allot- do pressures from population growth, . . . there are few remain nearly pristine, while others have ments and settlement schemes in many density or migration work alone. Put received extensive damage from natural countries, including industrialized coun- simply, human-induced biodiversity loss resource extraction, pollution and bio- places in the world tries, receive subsidies that weaken the can neither be fully understood nor can logical invasion. In more heavily settled abilities of markets to limit over-harvest- it be resolved, in practice, from this per- areas, a close association between where creating new ing.64 spective alone. Yet, in the presence of increasing population density and biodi- Ours is a world in which species, population growth, the notion of sus- versity loss appears clearer. Logically, many teetering on the brink of extinction, tainability is, as ecologist Edward reserves and passing the risks will be greater, and probably have no legal rights to continue existing. Wilson puts it, “but a fragile theoretical more difficult—and thus more expensive Biodiversity’s survival in an environment construct.”68 protective legislation —to avoid through regulation and of contentious politics, population growth, investment. economic inequity, and fast-paced global Ecologist Michael Soulé concludes are enough, by enterprise will, to a large extent, depend that failed institutions and rapid popula- on how well laws, policies and the mar- 51

tion growth have placed powerful con- Nature’s Place ketplace promote biological conservation. themselves, to save straints around what biological programs For this reason, the degree to which scien- can conserve of fading biodiversity. And tists and environmentalists are able to native species and because of these constraints, there are influence these institutions will be critical few places in the world where creating for biodiversity’s future. Here, developing new reserves and passing protective leg- ecosystems. countries lag. islation are enough, by themselves, to Presently, the developing world— save native species and ecosystems. home to around 80 percent of the world’s Sometimes these simple prescriptions population and the vast majority of its are not appropriate at all. Programs like biodiversity—can claim just 30 percent of agro-forestry, shade-grown coffee, pri- the world’s scientists and technicians.65 vately-owned ventures in ecotourism, Of these, a relatively small proportion and multi-use community property now work in fields directly relevant to schemes can be key components in biodiversity conservation, and a dispro- national biodiversity strategies. And portionate number of these are concen- when political systems are unstable in trated in Brazil, Mexico, India and East areas where population pressure contin- Asia.66 ues to build, there may be more hope Biodiversity, Property Rights and Population Growth

FIGURE 21 ver the past two decades, environmentalists have come to realize that marketing biodiversity’s many products, and People and Property Values—California, 1990 Oreturning the profits to local owners and caretakers, can pro- 100 • vide powerful incentives for conserving biodiversity. Still, on bal- 90 • ance, biodiversity has fared poorly in the global marketplace. More 80 • often than not, property rights (rules of use or ownership, and 70 • penalties for breaking those rules) are absent for wild species. At 60 • best, those rules are vague or hard to enforce. And typically, there 50 • is little accurate knowledge about the response of species to har- 40 • vest and use. Without adequate property rights and knowledge, 30 •

(millions of US $) (millions of and without affordable substitutes for evolution’s unique products, 20 • competition among suppliers has repeatedly overwhelmed conser- 10 • vation efforts and outcries of public concern. OF 1 SQUARE KILOMETER OF 1 SQUARE AVERAGE ASSESSED VALUE AVERAGE 0 •• • • • • • • • 1 200 400 600 800 1000 1200 1400 The passenger pigeon, for example, the most ubiquitous North POPULATION DENSITY American bird in the early 19th century and once a delicacy, owes (people per sq. km.) its extinction in part to markets. Today 69 percent of known fish stocks are in decline.1 Thirty-seven species of seahorses and 52 Property values tend to increase as local population grows, pipefishes are on IUCN’s Red List of Threatened Animals, most of making it difficult to purchase adequate land to protect species. Population Action International Source: Data from U.S. Census Bureau, 1998. them harvested to low levels to meet the demands of the Asian medicinal trade. And many other species—from the bluefin tuna, now fetching thousands of dollars per individual, to the African white rhinoceros, whose horn is more valuable than gold in parts of Asia—can thank market pressures for their positions on the edges of survival. So what does population growth have to do with it? Property rights protect productive work and investment, and try to minimize conflicts among resource users. It was likely that an increase in population density first motivated early societies to establish local systems of tenure—rights to use land, rivers and their resources.2 In today’s world, with 6 billion people and powerful commercial interests, strict property arrangements are more appropriate than ever. Economists have concluded that without property rights that are clear and enforceable, population growth can lead to greater demand and use of resources, and ultimately to over-harvest and depletion.3 References 1. M.E. Soulé, “Conservation: Tactics for a Constant Crisis,” Science 253 (1991): 744-750, p. 745. 2. The synopsis of the Forest Fragments Project borrows from a longer review in: E.O. Wilson, The Diversity of Life (Cambridge: Harvard Local conservation efforts are also affected. Population growth is among Univ. Press, 1992). factors elevating land prices, making it expensive to purchase or retain land 3. Fundação Tropical de Pesquisas e Tecnologia “André Tosello,” that is needed to establish and broaden species protection. Even when parks http://www.bdt.org.br/bdt/bdff/, 1993 (last accessed, February 10, and reserves are established, it is often difficult to keep large animals from 1999). 4. M.E. Soulé, Science 253 (1991): 744; J.A. McNeeley and others, harming property or people, or being harmed themselves near or beyond the “Human Influences on Biodiversity,” in Global Biodiversity boundaries of protected areas.4 And efforts to maintain the boundaries of Assessment, ed. V.H. Heywood (Cambridge: Cambridge Univ. Press protected areas in populous localities are often deemed impractical, expen- & UNEP, 1995); P. Stedman-Edwards, The Root Causes of sive or politically costly, particularly in the poorest countries.5 Biodiversity Loss: An Analytical Approach, Macroeconomics for Sustainable Development Office (Washington, DC: World Wide In the future, conservationists may also need to consider how population Fund for Nature, 1997); WRI, IUCN, and UNEP, Global Biodiversity growth relates to community-based resource management programs.6 These Strategy: Guidelines for Action to Save, Study and Use Earth’s Biotic programs have focused on arranging property rights in ways that distribute Wealth Sustainably and Equitably (Washington, DC: World benefits of commercial use of biodiversity to local people and thus encour- Resources Institute, 1992). age conservation. Perhaps the most widely recognized example is Zimbabwe’s 5. V. Dompka, ed. Human Population, Biodiversity and Protected Areas: Science and Policy Issues (Washington, DC: American Association Communal Areas Management Programme for Indigenous Resources (CAMP- for the Advancement of Science, 1996); P. Goriup, ed. Populations FIRE), which sets guidelines for community-based wildlife management out- and Parks, Parks 8, 1 (1998); S. Brechin, S.C. Surapaty, L. Heydir, side protected areas. This program distributed $1.6 million in profits to local and E. Roflin, “Protected Area Deforestation in South Sumatra, communities during 1995, over 90 percent of it from hunting fees.7 Indonesia,” George Wright FORUM 11, 3 (1994): 59-78. 6. D.J. Forester and F.E. Machlis, “Modeling Human Factors that Affect 53 Intriguingly, CAMPFIRE participants themselves have recognized the role of the Loss of Biodiversity,” Conservation Biology 10, 4 (1996): 1253- population growth in reducing the individual shares of wildlife-related rev- 1263; also see: R.F. Noss and A.Y. Cooperrider, Saving Nature’s Nature’s Place enues that now maintain local interest in protecting habitat and wildlife.8 Legacy: Protecting and Restoring Biodiversity (Washington, DC: Island Press, 1994). 7. R. Woodroffe and J.R. Ginsburg, “Conserving the African Wild Dog, References Lycaon pictus. I. Diagnosing and Treating Causes of Decline,” Oryx 1. FAO, Fisheries Circular, 920 FIRM/C920 (Rome: FAO, 1997). 33, 2 (1999): 132-142. 2. E. Boserup, in New Palgrave: A Dictionary of Economics, eds. J. Eatwell and others (New 8. R. Woodroffe, personal communications, 1999. York: Stockton Press, 1987). 9. R. Hoare and J. Du Toit, “Coexistence Between People and 3. E. Ostrom and others, Science 284 (1999): 278-282; NRC, Population Growth and Economic Elephants in African Savannas,” Conservation Biology 15, 3 (1999): Development: Policy Questions (Washington, DC: National Academy Press, 1986). 633-639; J.S.C. Parker and A.D. Graham, “Elephant Decline: 4. R. Woodroffe and J.R. 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(New York: John Wiley & Sons, 1994). 61. Organisation for Economic Co-operation and Goettsch Mittermeier, Megadiversity: Earth’s 50. S.R. Templeton and S.J. Scherr, “Effects of Development, “Financial Flows to Developing Biologically Wealthiest Nations (Mexico, C.F.: Demographic and Related Microeconomic Change Countries in 1998: Rise in Aid; Sharp Fall in Private Cemex, 1997). on Land Quality in Hills and Mountains of Flows,” Press Release (Paris: OECD, 1999). 43. L. Hannah, African People, African Parks Developing Countries,” World Development 27, 6 62. R. P. Cincotta and R. Engelman, Economics and Rapid (Washington, DC: Conservation International, (1999): 903-918. Change: the Role of Population Growth, PAI Occasional 1992); A. T. Durning, Guardians of the Land: 51. F. Smith, G. Daily, and P. Ehrlich, “Human Paper, 3 (Washington, DC: Population Action Indigenous Peoples and the Health of the Earth, Population Dynamics and Biodiversity Loss,” in The International, 1997). 1992. Economics and Ecology of Biodiversity Decline: The 63. D.C. North, Institutions, Institutional Change and 44. A. deSherbinin and M. Freudenberger, “Migration Forces Driving Global Change, ed. T. Swanson Economic Performance, (Cambridge: Cambridge Univ. to Protected Areas and Buffer Zones: Can We Stem (Cambridge, U.K.: Cambridge Univ. Press, 1995), Press. 1995), p. 16; I. Adelman, C.T. Morris, H. Fetini, the Tide?,” Parks 8, 1 (1998): 38-53. 125-141. and E. Golan-Hardy, “Institutional Change, Economic 45. O.J. Lynch and K. Talbott, Balancing Acts: 52. I.M. Goklany, “Saving Habitat and Conserving Development, and the Environment,” Ambio 21, 1 Community-Based Forest Management and Biodiversity on a Crowded Planet,” Bioscience 48, (1992): 106-110. 55

National Law in Asia and the Pacific (Washington, 11 (1998): 941-953; also see P. Waggoner, J. 64. N. Myers, “The World’s Forests: Problems and Nature’s Place DC: World Resources Institute, 1995); L. Sponsel, in Ausubel, and I. Wernick, “Lightening the Tread of Potentials,” Environmental Conservation 23, 2 (1996): Who Pays the Price: the Sociocultural Context of Population on the Land: American Examples,” 156-168; N. Myers, “Marine Fisheries: Two Macro Environmental Crisis, 1994. Population and Development Review 22, 3 (1996): Constraints,” Environment and Development Economics 46. M. Fort and L. Grandia, “Population and 531-545. 2 (1997): 91-96; D.M. Roodman, Paying the Piper: Environment in the Petén, Guatemala,” in Thirteen 53. V. Smil, “Population Growth and Nitrogen: an Subsidies, Politics and the Environment, Worldwatch Ways of Looking at a Tropical Forest, ed. J.D. Exploration of a Critical Existential Link,” Paper, 133 (Washington, DC: Worldwatch Institute, Nations (Washington, DC: Conservation Population and Development Review 17, 4 (1991): 1996); N. Myers and J. Kent, Perverse Subsidies: Tax $s International, 1999), 85-91; for rates directly sur- 569-601; P.M. Vitousek and others, Ecological Undercutting Our Economies and Environments Alike rounding the Calakmul Preserve, see J. Ericson, Applications 7 (1997): 737. (Winnipeg: International Institute for Sustainable M.S. Feudenberger, and E. Boege, “Population 54. D.M. Mageean and J.G. Bartlett, “Using Population Development, 1998). Dynamics, Migration, and the Future of the Data to Address the Problem of Human Dimensions 65. UN Development Programme, Human Development Calakmul Biosphere Reserve,” Program on of Environmental Change,” in GIS Solutions in Report 1998 (New York: Oxford Univ. Press, 1998). Population and Sustainable Development, Natural Resource Management: Balancing the 66. J. Cracraft, “Charting the Biosphere: Why We Must Occasional Paper, 1 (Washington, DC: American Technical-Political Equation, ed. S.A. Morain (Santa Build Global Capacity for Biodiversity Science,” Paper Association for the Advancement of Science, 1999); Fe, NM: OnWood Press, 1998), 193-205. presented at the National Academy of Sciences, F. Meyerson, “Guatemala Burning,” Amicus 55. L.R. Brown, G. Gardner, and B. Halweil, Beyond Washington, DC, October 29, 1997; J. Cracraft, “The Journal, Fall, 1999, 28-31. Malthus: Sixteen Dimensions of the Population Urgency of Building Global Capacity for Biodiversity 47. C. MacFarland and M. Cifuentes, “Case Study: Problem, Worldwatch Paper, 143 (Washington, DC: Science,” Biodiversity and Conservation 4 (1995): 463- Ecuador,” in Human Population, Biodiversity and Worldwatch Institute, 1998). 475. Protected Areas: Science and Policy Issues, ed. V. 56. UN Centre for Human Settlements, An Urbanizing 67. M.E. Soulé, Science 253 (1991): 744. Dompka (Washington, DC: American Association World: Global Report on Human Settlements, 1996 68. E.O. Wilson, The Diversity of Life, 1992, p. 328. V.V. HumanHuman PopulationPopulation GrowthGrowth andand thethe BiodiversityBiodiversity HotspotsHotspots

By concentrating on such areas espite the efforts of dedicated conserva- wilderness areas have been identified: the Upper tionists of many different nationalities, Amazonia and Guyana Shield, the Congo River where needs are greatest and where significant numbers of today’s living Basin, and forests of New Guinea and Melanesia. the pay-off from safeguard measures species will become extinct in the com- These are the most pristine and least fragmented ing decades. To minimize the loss to of all species-rich regions of the world, and among would also be greatest, conserva- Dfuture human generations, international environ- the last places in the tropics where indigenous tionists can engage in a more sys- mental policymakers, strapped by limited funds, forest-dwelling peoples have any hope of main- will have to act quickly, wisely and in the right taining their traditional lifestyles. An estimated 75 tematized response to the challenge locations. How will they manage to do this? percent or more of the naturally vegetated habitat In fact, a tool exists. Conceived by British ecol- of large-scale extinctions.1 remains in each of the three major tropical wilder- 56 ogist Norman Myers in the late 1980s,2 and expand- ness areas.3

Population Action International ed upon by Myers, Russell Mittermeier and scien- Norman Myers, 1988 tists at Conservation International, the global bio- What Makes the Ecologist diversity hotspots call attention to 25 terrestrial regions of the world where biological diversity is Hotspots So “Hot”? most concentrated and the threat of loss most Analysis of hotspots is based on the number of severe. In all of the hotspots, fully intact natural endemic species (species found nowhere else in ecosystems have already been reduced to 30 per- the world) of vascular plants. These are plants cent or less of their original land surface area. with internal vessels to conduct water and nutri- And in nine hotspots—including the Philippines, ents, like grasses, flowering plants, trees and Madagascar and Brazil’s Atlantic Forest Region— ferns. Although the intact, naturally vegetated intact natural habitats are down to less than 10 ecosystems within the hotspots cover less than 2 percent of their original extent.4 As presently percent of the Earth’s land surface, over 131,000 drawn, the boundaries of the 25 biodiversity species are found within these hotspots as endemics. hotspots enclose around 12 percent of the Earth’s These account for roughly 44 percent of the habitable land surface (omitting Antarctica and world’s plant diversity. In addition, the hotspots other areas of bare rock and ice). include habitat for thousands more plant species Along with the hotspots, three major tropical that are also found outside the hotspots.3 © Rebecca Janes Because high plant diversity is, by and conservation efforts. Rates of growth of to prevent biodiversity loss, even with large, a good indicator for a richness of ter- human population provide some insight significant regulation and investment. restrial animal species, the hotspots help set into the future hotspot population, and geographical priorities for world animal allude to densities it might achieve in Results of the Analysis conservation as well. The hotspots are esti- some localities. mated to contain somewhere around 35 In the following analysis by As of 1995, more than 1.1 billion people percent of all terrestrial vertebrates (which Population Action International, popula- were living within the 25 biodiversity excludes fish) as endemics. There are also tion density and growth rates have been hotspots. Population density in the indications that at least 75 percent of all ter- estimated for each of the hotspots and hotspots was, on average, almost twice restrial animal species listed as threatened major tropical wilderness areas. The that of the world as a whole. Despite by the IUCN-World Conservation Union are analysis uses geographical data from declines in human fertility in several found within this relatively small area.3 Conservation International; a map of regions of the world, this study suggests Hotspot analysis is an ongoing process. 1995 population density produced by that population growth, which ranges from Revisions to the current list are likely in the the National Center for Global 1.0 to 3.2 percent annual growth in 24 of future. And the global biodiversity hotspots Information Analysis, at the University the 25 hotspots, remains an important fac- As of 1995, more than are not the only world-wide conservation of California at Santa Barbara, California, tor in global biodiversity conservation. On average, population in the hotspots is priority system. Others include World Wildlife in the United States; and national and 1.1 billion people were Fund’s (WWF) global 200 ecoregions, sub-national population growth data growing by 1.8 percent annually, 38 per- BirdLife International’s endemic bird areas, from various sources.5 [See Appendices cent faster than the world population and WWF/IUCN’s centers of plant diversity.4 1f, g and j.] growth rate of 1.3 percent per year, and living within the 25 This method cannot assess the full even significantly above the developing range of risks on specific groups of world’s rate of 1.6 percent per year. biodiversity hotspots. 57

Future Risk and Uncertainty Nature’s Place organisms or species. And there are Around 75 million people, or 1.3 per- The fate of a significantly large proportion numerous sources of uncertainty, par- cent of the world’s population, presently of terrestrial biodiversity is linked to the ticularly at low levels of human popula- live within the three major tropical wilder- future of these 28 biologically diverse tion density. Here, human-caused dis- ness areas. These tropical forests cover regions. But what is that future, and what turbance can vary dramatically—native around 6 percent of the Earth’s land sur- are its risks? Realistically, we cannot know habitat could be nearly pristine, inhabit- face, an area larger than China. Among precisely. Economic and cultural factors, ed by relatively small groups of indige- Earth’s most biologically diverse regions, both global and local, will matter. So will nous people who subsist with little these forests are experiencing the most policy responses to biodiversity loss. And impact on the environment. Or, signifi- rapid growth in human population: 3.1 most of these are not measurable, or are cant biodiversity loss may have resulted percent annually, on average, a level over presently unavailable for evaluation. previous to widespread settlement, from twice the global rate of population growth. Population density and population land uses like logging, grazing, mining Growth rates for developed country growth have been measured. Both imply and hunting that have extracted natural populations situated in hotspots are, in risks to biodiversity, for both will assuredly resources, abetted biological invasion or most cases, substantially higher than the play important roles in determining the dumped pollutants. That variation worldwide average for developed regions, extent and nature of human dominion over diminishes with higher population den- which is 0.3 percent. Migration, both in ecosystems, and in the success or failure of sities, in which case it becomes harder present and past decades, is the principal Key to the Global Biodiversity Hotspots and Major Tropical Wilderness Areas

Global Biodiversity Hotspots 3. Caribbean 5. Chocó-Darién-Western Ecuador Original extent remaining intact: 11% Original extent remaining intact: 24% 1. Tropical Andes Original extent protected: 15.6% Original extent protected: 6.3% Original extent remaining intact: 25% Location: the Florida Everglades and the Location: coastal plains of Colombia, Ecuador, Original extent protected: 6.3% Caribbean Islands eastern Panama Location: highlands of Colombia, Ecuador, Vegetation types: tropical moist broadleaf forest, Vegetation types: tropical moist broadleaf Bolivia, Peru, Venezuela pine forests, wetlands, mangroves forests Vegetation types: tropical moist broadleaf for- Endemic plant species: 7,000 Endemic plant species: 2,250 est, dry forests, montane grasslands Hotspot area: 264,000 sq. km. Hotspot area: 134,000 sq. km. Endemic plant species: 20,000 Population: 38,780,000 Population: 5,930,000 Hotspot area: 1,415,000 sq. km. Population density: 136 persons per sq. km. Population density: 44 persons per sq. km. Population: 57,920,000 Population growth rate: 1.2% per year Population growth rate: 3.2% per year Population density: 40 persons per sq. km. Population growth rate: 2.8% per year Ancient flora and fauna, distinct from mainland. World’s richest assemblages of lowland plants Everglades contain some 11,000 species of seed- and animals. High rates of deforestation during Endemics include 320 bird, 558 reptile and bearing plants, 25 orchid varieties, 323 bird past half-century. Ecuador’s lowland wet forest amphibian species. Origin of several important species. Islands are regional centers for marine now below 10 percent of original cover. Species crops and genetic relatives. Two-thirds of origi- endemism. Species include the solenodon (small include cycad palms, jaguar, cotton-top tamarin, nal natural vegetation cover already lost. insectivores), Caribbean manatee, many endemic harpy eagle. Habitat for Peruvian yellow-tailed woolly mon- frogs, marine turtles. key, mountain tapir, spectacled bear, marble 6. Brazilian Cerrado 58 spatula-tailed hummingbird. 4. Atlantic Forest Region Original extent remaining intact: 20%

Population Action International Original extent remaining intact: 8% Original extent protected: 1.2% 2. Mesoamerica Original extent protected: 2.7% Location: central Brazil Original extent remaining intact: 20% Location: eastern coast of Brazil, eastern Vegetation types: tropical woodlands and savannas Original extent protected: 12.0% Paraguay, small area in northern Argentina Endemic plant species: 4,400 Location: Central America, from Panama north to Vegetation types: tropical moist broadleaf forest Hotspot area: 2,160,000 sq. km. central west coast of Mexico Endemic plant species: 6,000 Population: 14,370,000 Vegetation types: tropical moist broadleaf for- Hotspot area: 824,000 sq. km. Population density: 7 persons per sq. km. est, tropical dry forest, mangroves Population: 65,050,000 Population growth rate: 2.4% per year Endemic plant species: 5,000 Population density: 79 persons per sq. km. One of largest savanna-woodland complexes. Site Hotspot area: 1,099,000 sq. km. Population growth rate: 1.7% per year Population: 61,060,000 of commercial agricultural expansion. Population density: 56 persons per sq. km. Known in Brazil as Mata Atlantica, in Argentina Agriculture, charcoal production and water proj- Population growth rate: 2.2% per year as Selva Misionera o Paranaense. 54 percent of ects are main threats. Species include maned region’s trees, 80 percent of primates are endem- wolf, giant anteater, Spix’s macaw. Distinctive continental species. Winter range for ic. Less than 5 percent of once vast forest still many North American song birds. Ranching, intact. Coastal development and urban sprawl

© coastal development and agriculture pose seri- threaten remainder. Primates such as golden lion R e ous threats. Species include the resplendent b tamarin and black-faced lion tamarin endemic to e c quetzal, ocelot, mountain squirrel. c region, as are maned sloth, red-billed currasow. a J a n es 7. Central Chile FIGURE 22 Original extent remaining intact: 30% Original extent protected: 3.1% Population Density in the 25 Global Biodiversity Hotspots and Location: Chile Major Tropical Wilderness Areas, 1995 Vegetation types: mediterranean shrublands, temper- ate rainforest. Endemic plant species: 1,605 Hotspot area: 320,000 sq. km. Population: 9,710,000 Population density: 29 persons per sq. km. Population growth rate: 1.4% per year Chilean mattoral shrublands highly 15 diverse. Region includes only tem- perate rainforest in South America, 8 14 which is home to over 3,000 20 plant species. Natural vegeta- 3 tion reduced to less than one- 19 2 18 third of original. Most densely 21 25 populated part of Chile. 5 11 B A 25 10 16 59 8. California Floristic 6 1 17 C Nature’s Place Province 4 9 Original extent remaining 23 intact: 25% Population Density 13 7 (people per sq. km.) 22 Original extent protected: 9.7% 12 24 Location: the northern portion of the Greater than 50 Mexican state of Baja California, to 10 - 50 just north of the border of the U.S. state of California Less than 10 Vegetation types: mediterranean shrublands, coniferous forest Endemic plant species: 2,125 Hotspot area: 236,000 sq. km. Population: 25,360,000 Population density: 108 persons per sq. km. Population growth rate: 1.2% per year By 1995, population density (people per square kilometer) in the global biodiversity hotspots was, on average, Chaparral shrublands along coast are heavily threat- almost twice that of the world as a whole. Out of the 25 hotspots (numbered 1 to 25 on the map), 15 had attained densities higher than the world population density of 42 people per square kilometer. For the time ened. Mountain ranges home to ancient forest rem- being, the three major tropical wilderness areas (A, B, C) remain populated at relatively low densities. nants including redwoods and giant sequoias. Source: Population Action International; data from NCGIA/CIESIN, 1998. Region contains one-fourth of all plant species in the continental United States and Canada, half of which are endemic. 9. Madagascar and 11. Guinean Forests of 13. Succulent Karoo 15. Caucasus Indian Ocean Islands West Africa Original extent remaining intact: 27% Original extent remaining intact: 10% Original extent remaining intact: 10% Original extent remaining intact: 10% Original extent protected: 2.1% Original extent protected: 2.8% Original extent protected: 1.9% Original extent protected: 1.6% Location: southwestern Namibia, South Africa Location: Armenia, Azerbaijan, Georgia and Location: Madagascar and surrounding Location: from Nigeria along the southern Vegetation types: desert succulents small section of Iran islands, including the Comoros, Mauritius, portion of West Africa to Sierra Leone and Endemic plant species: 1,940 Vegetation types: temperate montane forests Mayotte, Reunion, Mascarene, Seychelles Guinea Hotspot area: 193,000 sq. km. Endemic plant species: 1,600 Vegetation types: moist tropical forest, dry Vegetation types: tropical moist broadleaf Population: 460,000 Hotspot area: 184,000 sq. km. forest, savannas, desert, mangroves forest, mangroves Population density: 3 persons per sq. km. Population: 13,940,000 Endemic plant species: 9,704 Endemic plant species: 2,250 Population growth rate: 1.9% per year Population density: 76 persons per sq. km. Hotspot area: 660,000 sq. km. Population growth rate: - 0.3% per year Hotspot area: 587,000 sq. km. Supports roughly 3,500 plant species, more Population: 15,450,000 Population: 68,290,000 than half endemic. Distinctive semi-desert One of the most biodiverse temperate forests Population density: 26 persons per sq. km. Population density: 104 persons per sq. km. communities, many over-grazed. Problems of Asia. High levels of plant and animal Population growth rate: 2.7% per year Population growth rate: 2.7% per year include over-pumping groundwater and ille- endemism. Remnants of European and Asian Some of most species-rich habitats in gal harvest of succulent plants. Species fauna, including Caucasian tur, chamoix, ibex, About three-quarters of Madagascar’s plants Africa. Many plants and animals distinct include centuries-old welwitschia, mountain red deer, wolf, bear, lynx. and animals are endemic. Lemurs, a threat- from Congo Basin. Mammals threatened by zebra, black rhino. ened group of primitive primates, are best poaching, including lowland gorillas and 16. Sundaland known mammals. Forests now at 20 percent chimpanzees. Species include West African of pre-human extent. Smaller ocean islands 14. Mediterranean Basin Original extent remaining intact: 8% mahogany, zebra duiker (a tiny antelope), Original extent remaining intact: 5% harbor distinctive fauna. crowned eagle-hawk. Original extent protected: 5.6% Original extent protected: 1.8% Location: Indonesian islands of Sumatra, Java Location: coastal and near-coastal parts of and Borneo, Brunei, peninsular and eastern 10. Eastern Arc Mountains and 12. Cape Floristic Province southern Europe, the Middle East and 60 Malaysia. Coastal Forests of Tanzania Original extent remaining intact: 24% North Africa Vegetation types: tropical moist forests, dry Population Action International and Kenya Original extent protected: 19.0% Vegetation types: mediterranean shrub- and monsoon forests, alpine meadows, man- Original extent remaining intact: 7% Location: South Africa lands, montane coniferous forests groves Original extent protected: 16.9% Vegetation types: mediterranean shrublands Endemic plant species: 13,000 Endemic plant species: 15,000 Location: eastern Tanzania Endemic plant species: 5,682 Hotspot area: 1,556,000 sq. km. Hotspot area: 1,500,000 sq. km. Vegetation types: tropical moist forests Hotspot area: 82,000 sq. km. Population: 174,460,000 Population: 180,490,000 Endemic plant species: 1,400 Population: 3,480,000 Population density: 111 persons per sq. km. Population density: 121 persons per sq. km. Hotspot area: 142,000 sq. km. Population density: 42 persons per sq. km. Population growth rate: 1.3% per year Population growth rate: 2.1% per year Population: 7,070,000 Population growth rate: 2.0% per year Population density: 50 persons per sq. km. Home to more than 10 percent of all plant Rainforest and mangroves highly biodiverse, Population growth rate: 2.2% per year Coastal shrubland, known as fynbos, may species, much of it in coastal shrublands but threatened by agriculture, logging, burn- have highest plant species density of any known as macchia. Southern European ing. Among richest flora in Asia. Includes rela- Once a site of profuse local evolution. Now comparably-sized land ecosystem. 70 per- mountains home to remnants of once tives of crop and orchard species. Region’s just half of original cover remains. cent of plant species are endemic. One-third diverse European fauna. Turkish Taurus mangroves important marine nursing grounds. Usambara Mountains alone contain 50 of original natural vegetation lost to agri- Mountains particularly rich in plant species. Species include Sumatran tigers, rhinos, gib- endemic tree species. Threatened by fire- culture and urban sprawl. Remainder Fauna include chamoix, brown bear, mar- bons, Sunda otter-civet, Bornean tarsier and wood collection, agriculture. Home to 18 of degraded and highly fragmented. bled polecat, Egyptian vulture. Until late orang-utans. 20 known species of African violets, 16 Roman Era, North Africa supported fauna species of wild coffee, numerous birds similar to present sub-Saharan plains, including Hartlaub’s turaco. including elephants, rhino and lion. 17. Wallacea Original extent remaining intact: 15% FIGURE 23 Original extent protected: 5.9% Population Growth in the 25 Global Biodiversity Hotspots and Location: central islands of Indonesia, including Sulawesi and Moluccas Major Tropical Wilderness Areas, 1995-2000 Vegetation types: tropical moist forests, mangroves Endemic plant species: 1,500 Hotspot area: 341,000 sq. km. Population: 18,260,000 Population density: 54 persons per sq. km. Population growth rate: 1.9% per year Extremely high levels of bird, mammal and plant endemism. Moluccan archi- 15 pelago includes hundreds of heavily 8 forested islands. Mix of Asian line- 14 20 ages, such as macaques and tar- siers, with Australian lineages 3 19 such as eucalyptus trees and 2 18 marsupials. 21 25 5 11 B 18. Philippines A 10 6 16 C Original extent remaining 25 1 17 C intact: 8% 4 9 23 61 Original extent protected: 1.3%

13 Nature’s Place Location: 7,100 islands of the 7 12 22 Philippines Population Growth Rate 24 Vegetation types: tropical moist forests Above 3.0% Endemic plant species: 5,832 2.0 - 3.0% Hotspot area: 293,000 sq. km. 1.0 - 2.0% Population: 61,790,000 Less than 1% [see 15] Population density: 198 persons per sq. km. Population growth rate: 2.1% per year Densely populated, population growing rapidly. Numerous vertebrates discovered in recent years. About 8 percent of original forest remains. Over 460 endemic vertebrates. Species include Despite significant declines in human fertility in several regions of the world, human population Philippine tarsier, colugo (flying lemur), monkey- growth, which ranges from 1.0 to 3.2 percent annual growth in 24 of the 25 global biodiversity eating eagle. hotspots (numbered 1 to 25), remains an important factor in global biodiversity conservation. The three major tropical wilderness areas (A, B, C) are, on average, experiencing more rapid growth in population than the hotspots. Population growth in these heavily forested regions, as a whole, is 3.1 percent each year, a level over twice the global rate of population growth. Source: Population Action International, see Appendix 1h. 19. Indo-Burma 21. Western Ghats and Sri Lanka 23. New Caledonia 25. Polynesia / Micronesia Original extent remaining intact: 5% Original extent remaining intact: 7% Original extent remaining intact: 28% Original extent remaining intact: 22% Original extent protected: 7.8% Original extent protected: 10.4% Original extent protected: 2.8% Original extent protected: 10.7% Location: Eastern Nepal to Eastern India Location: southwestern Indian states of Location: island of New Caledonia Location: Pacific Ocean islands, from the and Bangladesh, east to Vietnam and Karnataka and Kerala, southwestern Sri Vegetation types: tropical moist broadleaf Samoan Islands and the Federated States Hainan Island (China). Lanka and dry forests of Micronesia, to Fiji, and east to Hawaii Vegetation types: tropical moist broadleaf Vegetation types: tropical moist broadleaf Endemic plant species: 2,551 (U.S.). forest, dry and monsoon forests, man- forests Hotspot area: 16,000 sq. km. Vegetation types: tropical moist broadleaf groves Endemic plant species: 2,180 Population: 140,000 forests and dry forests Endemic plant species: 7,000 Hotspot area: 136,000 sq. km. Population density: 8 persons per sq. km. Endemic plant species: 3,334 Hotspot area: 2,313,000 sq. km. Population: 46,810,000 Population growth rate: 2.1% per year Hotspot area: 46,000 sq. km. Population density: 341 persons per sq. km. Population: 2,900,000 Population: 224,920,000 Endemism due to long geographic isolation. Population growth rate: 1.4% per year Population density: 58.4 persons per sq. km. Population density: 97.8 persons 80 percent of plants endemic. Wildly color- per sq. km. Population growth rate: 1.3% per year Among South Asia’s last remaining tropical ful flowers. Extraordinary endemic reptiles Population growth rate: 1.5% per year rainforests. Densely populated. Western and high degree of endemism among birds For some islands, over 95 percent of Richest endemic bird area in Asia. In Ghats home to 84 endemic amphibian and invertebrates. Original forests down to species are endemic. Majority of original Indochina highlands biologists recently cat- species. Very high tree diversity including less than 10 percent of island. Species land bird species extinct. Remaining native alogued 2 mammals: Vu Quang ox and giant 13 species of commercially valuable dipte- include the kagu (a flightless bird), terres- birds, plant species and invertebrates suc- muntjac. Home to tiger, golden langur, less- rocarp. Uniquely high rainfall forest in Sri trial crocodiles, giant gecko. cumbing to biological invasion. Species er panda, clouded leopard, gaur and Lanka. Species include Asian leopard, include Hawaii’s native hibiscus trees and kouprey (wild cattle), Javan rhinos, several Ceylon giant squirrel, Asian elephant, lion- 24. New Zealand flightless goose (nene), Fiji iguana, orange gibbons (apes), endemic pheasants, Asian tailed macaque, Malabar parakeet. dove. 62 Original extent remaining intact: 22% elephants and many rare plants. Original extent protected: 19.2% Population Action International Location: New Zealand’s North and South 20. Mountains of South- 22. Southwest Australia Islands Central China Original extent remaining intact: 11% Vegetation types: tropical moist broadleaf Original extent remaining intact: 8% Original extent protected: 10.8% forests and temperate rainforest Original extent protected: 2.1% Location: southwestern corner of coastal Endemic plant species: 1,865 Location: parts of the Chinese provinces of Australia Hotspot area: Sichuan, Gansu, Qinghai, and Tibetan Vegetation types: mediterranean shrublands 260,000 sq. km. Autonomous Region Endemic plant species: 4,331 Population: 2,740,000 Vegetation types: temperate forests, grass- Hotspot area: 107,000 sq. km. Population density: lands, alpine meadows Population: 1,440,000 11 persons per sq. km. Endemic plant species: 3,500 Population density: 13 persons per sq. km. Population growth rate: Hotspot area: 469,000 sq. km. Population growth rate: 1.7% per year 1.0% per year Population: 12,830,000 Two-thirds of 5,500 resident plant species Endemic species evolved separately Population density: 25 persons per sq. km. in coastal kwongan shrublands are endemic. from ancestors on mainland. Other Population growth rate: 1.5% per year Region well suited to agriculture, grazing than bats, no native mammals. Almost and urbanization. Introduced plants pose One of richest assemblages of forest trees all flightless birds now extinct. Grazing major threat. Species include Albany pitcher in the world. Many rare animals and plants and introduced species are greatest threats. plant, honey possum, and dragon orchid. endemic to this region, including numerous Species include the kauri tree, giant ferns, rhododendrons, the giant panda, golden kiwi, crested penguin. pheasant, and copper pheasant. source for this continued growth, specifi- cally in the U.S. states of California Major Tropical C. New Guinea and (California Floristic Province), Florida Wilderness Areas Melanesian Islands (Caribbean) and Hawaii (Polynesia and Area: 906,000 sq. km. Micronesia); and in Southwest Australia A. Upper Amazonia and Location: Indonesian state of Irian Jaya on and New Zealand. That growth is mainly Guyana Shield the island of New Guinea, Papua New produced by domestic re-location—people Guinea, Solomon Islands, Vanuatu Area: 5,830,000 sq. km. moving from colder localities to warmer Vegetation types: montane and lowland Location: east of the Andes Mountains in moist forests, mangroves spots along coastlines, and from cities to Colombia, Ecuador, Peru and Bolivia; the Population: 6,120,000 more natural settings6—mixed with immi- northern Brazilian Amazon Basin; the Population density: 6 persons per sq. km. southern parts of French Guiana, Guyana, gration from developing countries. Population growth rate: 2.6% per year Suriname and Venezuela One hotspot, the Caucasus of Central Vegetation types: tropical moist and inundat- Largest of all tropical islands, highest in Asia, is presently decreasing in population ed broadleaf forests altitude. Lowland forests harbor over 1200 (-0.3 percent annually), though it remains Population: 14,750,000 trees species, 2000 ferns. Home to world’s Population density: 3 persons per sq. km. largest butterfly, Queen Alexandra’s bird- among the ten most densely populated Population growth rate: 3.9% per year wing, bird-of-paradise species, echidna (an hotspots. And while densely populated egg-laying mammal), marsupial mammals. southern Europe is close to stabilization, Largest remaining continuous tract of tropical Small islands contain diverse birds and rainforest. Share of global biodiversity population is still growing at a net rate of plants, distinct from New Guinea. between 15 and 20 percent. Survival of 1.3 percent annually in the Mediterranean numerous indigenous Amerindian tribes tied hotspot, bolstered by rapid growth among to fate of forest region. Forests target for Sources: Middle Eastern and North African coun- extraction of tropical timber, pulp, gold, rub- “Global Biodiversity Hotspots” (Washington, 63 ber and wildlife for international pet trade. tries within the hotspot. DC: Conservation International), Nature’s Place http://www.conservation.org/web/fieldact/ho B. Congo Basin tspots/hotspots.htm, (last accessed Jan. 8, Area: 2,886,000 sq. km. 1999). Implications Location: west central Africa, northern Angola D.M. Olson and Eric Dinerstein, “The Global Population trends in the biodiversity to Cameroon and east to Rwanda, most of 200: A Representation Approach to hotspots and major tropical wilderness Democratic Republic of the Congo Conserving Earth’s Distinctive Ecoregions,” Vegetation types: tropical moist and broadleaf areas suggest that the risks of continuing Draft Manuscript (Washington, DC: World species loss are high in the most biological- forests, upland dry forest, mangroves Wildlife Fund, 1998). Population: 54,040,000 ly diverse terrestrial regions of the world. Population density: 18 persons per sq. km. Human population density is already a sig- Population growth rate: 3.0% per year nificant concern in about three-quarters of Some of richest and most intact forests in the the hotspots, particularly the Western world. Eastern Congo particularly rich in Ghats/Sri Lanka, the Philippines and the ancient species. Species threatened by hunt- ing, logging. Home to bonobo (pygmy chim- Caribbean. The hotspots are rapidly urban- panzee), pygmy hippo, okapi, crowned crane, izing. Currently there are 146 major cities forest elephant, recently described suntailed presently located in or directly adjacent to a monkey, rare orchids and butterflies, weaver hotspot. Because of their mild climates and birds and sunbirds. locations near coastlines, mediterranean shrublands (regions with climates and vege- dwindling indigenous Amazonian popula- ing agencies, many of which have tation similar to the Mediterranean Basin) are tions is roughly 20 years below the Brazilian increased funding to biodiversity programs attractive to human settlement. Within the 25 average of 66—and it is falling.8 over the past decade. Each agency must hotspots lie 62 cities having over 1 million Tropical wilderness areas are at a cross- decide how to invest: whether to concen- inhabitants each. Of these, 22 are within the 5 roads. Policies applied to these forests have, trate efforts in the hotspots where the hotspots dominated by mediterranean shrub- in the past, resembled those in western threats are most immediate, and the lands. North America in the late 19th century that remainder of unprotected biodiversity-rich Together, unsustainable natural resource granted land to migrants, and concessions habitat is relatively small; or to dedicate extraction and the persistent spread of agricul- for logging, mining and grazing. In general, the lion’s share of its funds to establish Whatever strategies ture pose a dual threat to tropical forest habi- the results have been the same: rapid defor- reserves enclosing much larger tracts of tat. Within the Southeast Asian hotspots estation, loss of natural ecosystems, and rainforest in the tropical wilderness depopulation of native peoples. Yet, there areas.11 ultimately emerge, alone—the Philippines, Wallacea, Sundaland and Indo-Burma—cropland grew by some 11 is still time in the tropics to change the Whatever strategies ultimately emerge, million hectares (roughly the size of outcome. Recently the government of geographical patterns of human popula- geographical patterns of Bulgaria) in the decade prior to forest surveys Suriname, with assistance from the tion density, growth and migration will taken in 1992-94.7 Nearly all of this new crop- Global Environmental Facility and continue to influence decisions in global human population land was cleared from forest. More recently, Conservation International, created the biodiversity conservation.12 Future demo- rates of deforestation appear to have accelerat- Central Suriname Nature Reserve by put- graphic patterns, however, are themselves density, growth and ed, assisted by burning in 1997 and 1998, and ting aside some 16,000 square kilometers uncertain. To some extent local population by commercial logging that was stepped up of rainforest (roughly equivalent to the density and migration, particularly as they during the recent Asian economic crisis. area deforested annually in the Brazilian operate by the middle of the 21st century, 64 migration will continue to Although fertility rates in Brazil and Amazon).10 More large tracts could be will be influenced by how quickly the Population Action International Indonesia have fallen dramatically over the reserved for future needs, some as man- ongoing global revolution in reproductive influence decisions in past decade, pro-migration policies undermine aged natural resource areas and indige- self-determination is extended to couples any likelihood that high rates of population nous reserves, others as national parks, in the biodiversity-rich tropics. global biodiversity increase in the three tropical wilderness areas recreation sites and research stations. will slow in the immediate future. A half-cen- References tury ago these areas were almost exclusively 1. N. Myers, “Threatened Biotas: Hotspots in conservation. the domains of indigenous hunter-gatherers. Population and Global Tropical Forests,” The Environmentalist 8, 3 Today, only the Amazonian and Guyanan Biodiversity Strategies (1988): 178-208, p. 187. 2. N. Myers, The Environmentalist 8, 3 (1988): forests have densities of less than five people One of the most important tasks for con- 178; N. Myers, “The Biodiversity Challenge: per square kilometer. And even here, low servationists in the 21st century will be to Expanded Hot-spot Analysis,” The population density is likely to be short- determine where to salvage the scant Environmentalist 10, 4 (1990): 243-256. lived. The area’s population growth rate, at remains of evolution’s legacy. To that end, 3. R.A. Mittermeier, N. Myers, J.B. Thomsen, G.A.B. da Fonseca, and S. Olivieri, “Biodiversity 3.9 percent per year, is the highest of the the hotspots and other global biodiversity Hotspots and Major Tropical Wilderness Areas: three tropical wilderness areas. If growth prioritization systems are essential tools. Approaches to Setting Conservation Priorities,” continues at this rate, the area’s mostly Yet, knowledge of the global biodiversity Conservation Biology 12, 3 (1998): 516-520 immigrant population would double in under hotspots does not eliminate a fundamental 4. D.M. Olson and E. Dinerstein, “The Global 200: 19 years. Already, life expectancy at birth for a Representation Approach to Conserving dilemma for international donor and lend- Earth’s Distinctive Ecoregions,” Draft Manuscript (Washington, DC: World Wildlife Fund, 1998); A.J. Stattersfield, M.J. Crosby, A.J. Long, and D.C. Wege, Hotspot Population Profile: Madagascar Endemic Bird Areas of the World: Priorities for Biodiversity Conservation (Cambridge, U.K.: BirdLife International, 1998); WWF and IUCN, Centres of Plant Diversity: A Guide t is on tropical oceanic islands that evolution seems most and Strategy for Their Conservation, Vols. 1-3 (Cambridge, U.K.: IUCN, 1994 - 97). wondrously productive. Left in isolation from mainland 5. W. Tobler, U. Deichmann, J. Gottsegen, and K. Maloy, “The Ipredators and competitors, given tens of millions of years Global Demography Project,” Technical Report, 95-6 (Santa and just a modest few forms to start with, its processes have Barbara: National Center for Geographic Information produced entirely new and unusual repertoires of species. Analysis, Univ. of California, Santa Barbara, 1995). 6. D.M. Mageean and J.G. Bartlett, “Using Population Data to Madagascar, the islands of the Caribbean Sea, Polynesia and Address the Problem of Human Dimensions of the Philippines are among the best examples. Nowhere does Environmental Change,” in GIS Solutions in Natural organic evolution seem more wildly creative—almost exper- Resource Management: Balancing the Technical-Political imental—as on these islands. And nowhere today are evo- Equation, ed. S.A. Morain (Santa Fe, NM: OnWood Press, 1998), 193-205. lution’s creations more threatened. 7. Calculated from cropland expansion data for countries Two major events shaped Madagascar’s biodiversity. within the 4 Southeast Asian hotspot boundaries men- The first was its separation from Africa around 180 tioned in the text. Data are from FAO, and published in: million years ago, setting off a burst of isolated evo- World Resources Institute, World Resources, 1998-99: lution among plant and animal life. The second was Environmental Change and Human Health (New York: Oxford Univ. Press, 1998). the arrival of Homo sapiens less than 2,000 years 8. UN Economic and Social Council, “Review of ago from somewhere in the Indonesian islands. Not Developments Pertaining to the Promotion and long afterwards, much of what evolution had fash- Protection of Human Rights and Fundamental Freedoms ioned forever disappeared. 65 of Indigenous Peoples: Health and Indigenous Peoples,” E/CN.4/Sub.2/AC.4/1996/3/Add.2 (New York: U.N., Among the animals that thrived until our own Nature’s Place 1996). species set foot on Madagascar was the flightless ele- 9. Brazil National Institute for Space Research, Monitoring phant bird, one of the largest birds that ever lived. A the Brazilian Amazon by Satellite, 1997 – 1998 (Sao Paolo: pygmy hippopotamus also went extinct, along with a Instituto Nacional de Pesquisas Espaciais, 1999); J. Craig, “Ravaging of the Amazon Continues Survey Shows,” giant tortoise and an aardvark. Two giant lemurs— Reuters, Jan. 26, 1998. Archaeonindris, which was larger than a male gorilla, and 10. L. Asato, “New Partnership Backs Suriname’s Forest Megaladapis, as big as a female gorilla—disappeared after Protection Efforts,” Press Release (Washington, DC: human arrival, as did a large tree sloth-like lemur called Conservation International), http://www.conservation. Alan busch 1 org/web/news/pressrel/99-0513.htm, May 13, 1999 (last Born Babakotia. Today humans and their livestock are the only ani- 2 accessed, June 3, 1999). mals on Madagascar weighing over 12 kilograms. 11. R.A. Mittermeier and others, The Global Biodiversity Despite the losses, Madagascar remains biologically unique. Hotspots (Mexico, D.F.: Cemex, 1999). Roughly 80 percent of Madagascar’s plants are endemic. And 12. M.E. Soulé, “Conservation: Tactics for a Constant Crisis,” Science 253 (1991): 744-750; E.D. Wikramanayake and oth- though the island, which is considered part of Africa, repre- ers, A Conservation Assessment of the Ecoregions of the sents less than 2 percent of that continent’s land, it is home Indo-Pacific region (Washington, DC: World Wildlife to fully a quarter of all African plant species. More species of Fund/US, in press). orchids are native to Madagascar than to the rest of Africa. Thirty species of reptiles and 178 species of frogs—staggering numbers for one island—have been recorded 15.4 million by 1998. from the UN Population Fund (UNFPA) esti- there to date, and more are discovered each Four out of five of the country’s workers mates that Madagascar falls short of meeting year. are farmers. And three out of four earn less the present demand for contraception among All the world’s 32 species of lemurs live than $1 a day.4 Less than one-fifth of a low-income couples by $650,000 a year.6 on Madagascar and nearby islands, and hectare of cropland is available per capita, nowhere else. Twenty lemur species are one of the lowest such figures in the world. threatened with extinction, four with only To feed their families, new generations of Community-Based Population slim chances for survival. Less recognized is a Malagasy farmers have moved further upslope, and Environment second completely endemic family of small, burning the island’s remaining tropical forests The need for family planning and maternal primitive insect-eating mammals, the from the hillsides of its eastern region, and health services appears greatest in Malagasy tenrecs, compris- planting its thin soils with upland rice. Madagascar’s countryside, where infant and Madagascar 2000 Years Ago ing 30 species. IUCN-World Madagascar’s remaining woodlands cover less child mortality is nearly one-third higher than Conservation Union classi- than 20 percent of that which Malay mariners in urban areas. However, Madagascar’s Health fies 10 of these as threat- encountered some 15 centuries ago. Then, Ministry is understandably hesitant about try- ened.3 perhaps, the island held opportunities for the ing to move reproductive health services into new migrants. Today, Madagascar’s farming the countryside when demand for family plan- families are typically poor, conservatively tra- ning goes unfulfilled in the island’s rapidly Our Own Species ditional, and situated far from the meager growing cities. Most of the few efforts to pro- During the latter half of the rural services that their government provides. vide such services are run by non-governmen- 66 20th century, dramatic Recent surveys show that Malagasy women tal organizations—including several managed

Population Action International demographic changes express the desire for somewhat smaller fami- by environmental organizations focused on occurred in Madagascar. lies—on average, one child less than the saving Madagascar’s remaining biodiversity. Responding to modest present six children per woman recorded. Since 1995, APPROPOP, a program sponsored by improvements in public About 19 percent of women who lack access the U.S. Agency for International health conditions, mortality to family planning services would like to use Development, has linked local health Original rates declined in the mid- contraception to limit childbirth. Another 16 providers to environmental field projects, Forest Cover 1950s, while fertility rates percent want to lengthen the period between each at the edge of a protected area, where remained high. As a result, births. Studies suggest that delayed child- community-based natural resource projects Mangrove Tropical Moist Forest the rate of annual popula- bearing could substantially reduce infant mor- are already active. One is located near the Tropical Dry Forest tion growth climbed to 3.4 tality.5 It could also slow the growth of popu- Mostly Non-Forest Zahamena Integral Reserve, one near percent by 1985. The valleys lation by spreading out the time between Ranomafana and another near Andohahela of Madagascar’s central generations. National Parks.7 Source: Data from WCMC. plateau filled with farms Despite the gravity of reproductive health These projects have tried to minimize and began to urbanize. In less than 50 years, needs, Madagascar’s budget for family plan- habitat loss in and around the parks while the island’s population more than tripled, ning services is only one-fifth the amount developing and encouraging sustainable growing from 4.2 million in 1950 to about spent on conservation efforts. A spokesperson income-generating practices in the same gen- eral areas. In Ranomafana local villagers could attract more settlers to project sites. manage tourist campsites, returning pro- In Madagascar, however, population is pro- ceeds to committees of village elders. Half jected to triple or quadruple by 2050. There of park admittance fees return to village can be no illusion that failing to provide communities for use in conservation services for populations in wildlife-rich areas projects.8 will dissuade people from living there. On These community-based initiatives pro- Madagascar, biodiversity’s last hope lies in a vide materials and train community members partnership with its people. And that part- in a variety of environmentally sound liveli- nership requires not only effective natural hoods, from community gardening and resource management but quality health care Madagascar 1995 small-scale aquaculture to beekeeping and —including family planning services for ecotourism. For their part, health providers those who seek them. on the projects operate mobile health units offering basic health care as well as family References planning information. 1. R.E. Dewar, in Quaternary Extinctions: A Prehistoric Concern about demographic pressures on Revolution, eds. P.S. Martin and R.G. Klein (Tucson: Univ. of Arizona Press, 1984). wildlife is no doubt among the concerns 2. P. Harrison, The Third Revolution (London: I.B. that motivate these partnerships, which Tauris, 1992). combine local and foreign development 3. IUCN Red List of Threatened Animals (Gland: IUCN, workers. But an equally important motiva- 1996). 67 4. World Development Indicators 1997 (Washington, tion is simply to respond to pressing health DC: World Bank, 1997). Nature’s Place needs—needs often articulated clearly by 5. G. Refeno and others, “Madagascar: Enquete TheThe valleysvalleys ofof women and other community members Nationale Demographiqe et Sanitaire, 1992,” themselves. Synthesis Report, Demographic and Health Survey (Antananrivo, Madagascar: Centre National de Projects that link natural resource con- Madagascar’sMadagascar’s Recherches sur l’Environnement, 1994). Current Forest Cover servation with family planning and repro- 6. R. Harrabin, “Madagascar: Growing Population Remaining Forest cover ductive health services tend to view eco- Fuels Environmental Crisis,” The Guardian Population Density centralcentral plateauplateau nomic development, education and people’s (London), Wed., June 30, 1999. More than 300 7. E. Rabelhasa and D. Whyner, “Evaluation Finale 150 - 300 control over their own fertility as interrelat- des AAPS Environmentaux,” Report 50 - 150 filledfilled withwith farmsfarms ed and vital to both community well-being 15 - 50 (Antananarivo, Madagascar: Appui au Programme 5 - 15 and environmental sustainability. The demo- de Population/Planification Familiale, 1998). 0 - 5 graphic bonus, if one develops, is merely 8. Institute for the Conservation of Tropical andand beganbegan toto one among several important benefits that Environments, “Conservation Efforts,” (Stony Source: Data from WCMC, NCGIA/CIESIN. Brook, NY: State Univ. of New York, Stony result from this approach. Brook), http://notes.cc.sunysb.edu/CAS/ urbanize.urbanize. Some conservationists warn that icte.nsf/webform/conservation, February 5, 1998 improved services and training programs (last accessed, December 5, 1998). Alan Bornbusch Hotspot Population Profile: Urbanization in the California Floristic Province

ot all of the global biodiversity hotspots are situated in the trop- As with all such correlations between human population ics. Endemic plant species—the biological criteria for hotspots— growth and biodiversity, no method for quantifying the causal Nare found in great diversity in mid-latitude coastal shrublands that relationship is readily apparent. But a quick glance at the Los are graced with mild and stable mediterranean-like climates. Five such Angeles metropolitan area, home to nearly 14.5 million hotspots have been identified: the California Californians (1997 estimate), makes clear how inhospitable Floristic Province in the United dense human settlement can be for wild species. After decades States, Southwest Australia, the of population growth and suburban development, the Los Cape Floristic Province of Angeles-Anaheim-Riverside urban conglomerate covers about South Africa, Central Chile 88,000 square kilometers, an area a little larger than the state and the Mediterranean of Maine.2 The area’s crowded highways carry more than 7 cars Basin itself. for each 10 of the area’s human beings.4 And its sanitation sys- These five hotspots tems release around 800 million gallons (3 million metric tons) are also preferred human of minimally treated sewage directly into the Pacific Ocean habitat. Within their every day, placing nearby marine life at risk.5 boundaries lie nearly 40 California’s growing economy has offered mobility to millions percent of all the urban areas who have migrated from other parts of the United States, from that have reached 1 million inhabi- Latin America and from Asia. The scale of growth and many of 68 Sally tants within the 25 hotspots. its impacts, on humans as well as on biological diversity, are Ethelston Population Action International Among the most notable clashes between biodiver- nonetheless clear. California can claim more threatened species sity and human population growth is one at the western edge of the than any other U.S. state except Hawaii. In 1997, 200 of its continental United States, extending southward onto the Baja California species were listed by the U.S. Fish and Wildlife Service as Peninsula of Mexico. This hotspot, the California Floristic Province, is endangered, including the famed northern spotted owl. Even the witnessing some of the most rapid population growth in the industrial- official “state mammal,” the grizzly bear, survives only on the ized world, with few signs of the slowdown that characterizes popula- state flag. It disappeared from California’s forests in 1922.5 tion growth in much of the rest of the world. Nearly half the plant species that are unique to the United States References are found in this modest-sized hotspot, along with an estimated 30,000 1. R.F. Noss and R.L. Peters, Endangered Ecosystems: A Status Report on species of insects, 341 birds, 145 mammals, 61 reptiles and 37 amphib- America’s Vanishing Habitat and Wildlife (Washington, DC: Defenders of ians. Outside of Australia and New Zealand, no other similar-sized area Wildlife, 1995). 2. U.S. Bureau of the Census, Doc. ST-97-1 (Washington, DC: U.S. Dept. of of a developed country can compare.1 Commerce, 1997). Yet consider what California has lost as its population has grown 3. R.A. Mittermeier and others, Megadiversity: Earth’s Biologically from fewer than 1 million people in 1850 to more than 34 million at Wealthiest Nations (Mexico, C.F.: Cemex, 1997). the end of the 20th century.2 Only 1 percent of the state’s original grass- 4. U.S. Federal Highway Administration, Selected Highway Statistics and land remains, as does just 5 percent of its once-pervasive redwood Charts (U.S. Dept. of Commerce, 1995). 5. S. Shroeder, California Population Project: Protecting the Environment by 3 forests and 6 percent of its interior wetlands. Reducing the Birth Rate (Sacramento, CA: Planning and Conservation League Foundation, 1996). VI.VI. StrategiesStrategies

The protection of … major parks and he current rapid rate of species extinc- A Plan of Action tion, out of all proportion with back- Each of us can take action to preserve the reserves is conceivable, if there is a ground rates and thus clearly related planet’s wealth of living species. This report’s to human activities, should warn us willingness to share resources on a recommendations are addressed to policymak- that society is approaching a classic ers, to scientists and conservationists, and to global level – to provide major support Tdouble bind. Continued population growth the general public: from industrialized countries not and steady increases in per capita consump- tion mean that we are accumulating more • The conservation of biological diversity merely for the protection of parks and needs and more wants, much of which can should be elevated to a high priority in donor agencies, nations and communi- reserves but for the creation of condi- only be satisfied by the biological world around us. Yet, in failing to conserve biodi- ties. While innovative conservation pro- tions in which all people can live with versity, humanity is simultaneously eliminat- grams deserve support and funds, there is a pressing need to encourage broader a measure of human dignity. The deci- ing those naturally endowed options that may be key to improving our own lives, and understanding of biodiversity and its 69 sive factors will be social, political, the lives of our descendents. value to society. To further this objective, Nature’s Place It will take decades, even centuries, to governments and donors should work to and economic; they will not be limited secure the long-term survival of the richest expand the ranks of biodiversity scien- simply to [society’s] willingness to possible diversity of non-human life. This is tists and environmental educators in the one reason the future growth of human species-rich tropical countries. conserve.1 population is so critical an issue— Work should continue on innovative approach- and so important to address in es to biodiversity conservation, especially Peter H. Raven, this context. Policies that lead financial mechanisms that spread the cost of 1986 to a stabilized human popu- such strategies among all who can afford lation, though often missing them. The biodiversity that finds its home in Evolutionary in recommendations for con- poor countries matters to the survival and Botanist serving biodiversity, may be quality of life of all humanity. Mechanisms Rio among the most important in the de need to be developed that encourage all nations Director, Missouri Ja neir long run. And they must work in to shoulder the costs of species preservation, o, Vic ky Hancock Botanical Garden tandem with strategies that act more directly wherever it occurs, according to their capacity to limit further losses of species and maintain to pay and the benefits they and their descen- functioning ecosystems. dants will derive. Subsidies that lead to biodiversity loss To succeed in the long term, conserva- Convention on Biological Diversity. This should be ended, and biodiversity man- tionists will need to influence the underly- international treaty is designed to estab- agement plans should become key ele- ing conditions that drive biodiversity loss. lish rights to original genetic materials ments in national and community plan- Many scientists no doubt consider a broad- and promote commercial incentives that ning. Efforts are needed to more accurate- er role in development to be outside their encourage nations to identify, conserve ly assess and publicize the long-term value expertise. Yet, most of the larger conservation and thoughtfully manage those species of functioning ecosystems and the species organizations—IUCN-World Conservation and ecosystems within their national . . . legislation that they shelter. And legislation that specifical- Union, the World Wildlife Fund and boundaries. So far, 175 countries have ly protects species—such as the Conservation International among them— ratified the Convention on Biological Endangered Species Act in the United have integrated social scientists into their Diversity.2 Despite the importance of this specifically protects States—deserves support in all countries, professional (and mostly biologically-trained) treaty to global conservation, the United as do measures designed to keep intact staff. These organizations see the need to States is not one of them. Clearly, it species—such as the natural terrestrial, aquatic and marine influence social and economic conditions, should be. ecosystems. National and community including those that affect population growth, Human population and its dynamics Endangered Species Act in planning should require that economic so that their biological programs can succeed. go unmentioned in the Convention on development not put at risk critical biolog- Biological Diversity, despite language call- • The Convention on Biological ical resources that can never be replaced. ing for minimizing adverse impacts on the United States— Diversity, an international agreement Education on the value of biodiversity biodiversity. Clearly, biodiversity will fare aimed at maintaining the planet’s bio- is vitally needed now. Most policymakers worse if population size and density fol- diversity and equitably sharing its deserves support in all and much of the general public cannot low high-growth scenarios rather than benefits, deserves the support of all define the term biodiversity and have little low-growth ones. Just as clearly, a range nations and peoples. Negotiators 70 idea why scientists and conservationists of social policies and programs will ulti- countries, as do measures seeking to improve it and further its Population Action International find its accelerating loss alarming. That mately influence the future of biodiversi- progress should consider the interac- loss is unlikely to be reversed until those ty. Among them are population programs designed to keep intact tions between species survival and who care about it find effective ways to consistent with the Programme of Action human population dynamics. By communicate biodiversity’s importance agreed to by 179 countries (including the slowing the growth of population natural terrestrial, aquatic and beauty to the news media and the United States) at the 1994 International while improving the capacity of all general public. Conference on Population and Development people, especially women, to manage and marine ecosystems. International donors can do more to (ICPD) in Cairo. their own lives, the social investment increase the number of professionals spe- The ICPD Programme of Action affirmed strategies called for at the 1994 cializing in biodiversity. Developing coun- the principle that population policy must International Conference on tries, where the vast majority of biological be based in social investments aimed at Population and Development support diversity resides, face extreme shortages of human development and in the rights of and amplify other measures to con- biodiversity scientists and technicians with women and men to determine for them- serve Earth’s complex web of life. biodiversity-relevant skills. Developing selves the timing of childbirth and the countries also need more and better equipped At the 1992 Earth Summit (the UN size of their families. Among the most environmental watchdogs and advocates, Conference on Environment and important of these social investments is and programs that promote an environ- Development) in Rio de Janeiro, the the provision of family planning services mentally-aware and educated public. world’s nations agreed to the text of the for all who seek to use them, and that includes the vast majority of the world’s On the following point few experts demographic change on ecosystems and approximately 1.5 billion women of would disagree: for worldwide biological wildlife populations, more research may reproductive age. A recent study con- conservation efforts to be successful, agri- help scientists learn how to retain critical cluded that nearly 40 percent of all preg- culture and human settlement (housing aspects of biodiversity in certain human- nancies worldwide are either mistimed and basic services, such as power, water dominated ecosystems. or not intended at all, suggesting that and waste disposal) will have to become The survival of many • Where organizations work in remote the world’s nations still fall far short of several times more land- and water-effi- rural areas to promote biodiversity offering sufficient services, information cient and far less polluting than they are conservation, conservationists should plant and animal species and personal freedoms for couples to today. In poor agricultural economies, consider cooperating with qualified successfully manage their own reproduc- development that includes massive job providers of reproductive health serv- tive lives.3 Governments should support creation in urban areas, land equity in will depend on ices. They can do so without jeopard- the policies agreed to at the ICPD in rural areas, and serious protection and izing their mission in conservation by 1994. These policies would facilitate an management of forests will likely be need- investments made today, working as part of broad-based efforts early peak in the size of human popula- ed to halt tropical deforestation. to promote community development, tion while immediately improving the Put simply, society should invest in address basic human needs, and both directly in well-being of women and their families. conserving biodiversity just as it invests in improve the management of natural Efforts to address human population harvesting it. If humanity would apply to resources that sustain human and growth and biodiversity loss go hand in conservation a mere fraction of the finan- biodiversity conservation non-human life. hand. And the survival of anything like cial resources and technological genius the present panoply of plant and animal that it has applied to increasing grain and As women have increasingly stepped and in human species will depend on investments made fish yields and modifying the landscape, forward to ask for access to family plan- ning services, some conservation and 71 today, both directly in biodiversity con- biodiversity’s future might look consider- development efforts that servation and in human development ably less bleak than it does today. community-development organizations Nature’s Place efforts that end up, as a side benefit to Eliminating subsidies that induce unsus- working in the field have begun respond- end up, as a side benefit their main purposes, slowing the growth tainable natural resource use would serve ing by entering into partnerships with of human population. the same purpose. reproductive health service organizations. Scientists can do more to help policy- These partnerships respond to explicit to their main purposes, • The public and private sectors should makers understand the implications of requests for services emanating from cooperate to diminish the environ- population growth on biodiversity. Much communities themselves. The most direct mental impacts of the expansion of slowing the growth of more research is needed, particularly benefit is that such communities are bet- agriculture and housing. Significant related to how changes in population den- ter able as a result to manage their natu- investments in research and improved human population. sity, lifestyles and land-use practices influ- ral resources and thus their stewardship standards in engineering and zoning ence long-term processes associated with of biological assets that surround them. for these sectors could help minimize biodiversity decline. When long-term data An added benefit of including family the conflict between efforts to con- is unavailable, studies that sample along a planning services in such integrated or serve biodiversity and efforts to allevi- path of increasing human density, from linked-service efforts is that population ate poverty and accommodate the near-pristine ecosystems to urban ecosys- growth is likely to slow as a result of population growth that occurs during tems, can be a revealing analytic tool. later childbirths and smaller families. At the next several decades. Besides documenting the influence of least 48 community-based projects or groups of projects worldwide now link that are associated with the demographic sustainable forestry, or tuna caught using conservation and natural-resource man- future. methods that spare porpoises, obliges the agement efforts with the provision of Rates of population growth tend to private sector to recognize biological reproductive health services to those who change slowly in the short term, but diversity’s value on its own terms. request them. In some cases such proj- aspects of society that bear upon fertility Supporting conservation organizations, ects are able to supply remote popula- can change rapidly. Among the most contributing to their purchase of critical tions with contraceptive options that important of these aspects is improved habitat, their activism on endangered At least 48 community- were otherwise unavailable. The single access to a range of choices in modern species and on reducing greenhouse gas most important component in successful contraception and other reproductive emissions, helps policymakers and busi- community-based projects appears to be health services. Similarly, delays in the ness leaders take measure of the public’s based projects or groups the active engagement of women. But it age of marriage for women, increases in concern about biodiversity loss. And the also requires that conservationists and the time interval between births, improve- way we vote, our presence at public of projects worldwide now others helping to sponsor such linked- ments in girls’ enrollment and education- meetings and interchange with the service projects be adaptable and willing al achievement, and increased female media, can eventually transform land use link conservation and to learn about human needs outside their employment and better job mobility all and water policies into those that main- area of expertise.4 could result in slower population growth tain natural ecosystems and native and lower peaks in future population size. species over the long term. Consumers natural-resource • In research publications and other today remain largely unaware of their communications, scientists and edu- • Consumers should learn about and own potential to help sustain biodiversity. management efforts with cators should use the range of future consider the role of their purchases, population possibilities—the high and their pets, and their daily activities in • Couples and individuals should con- 72 low scenarios projected by the United putting biodiversity at risk. They sider the impact of their reproductive the provision of Nations—rather than the medium sce- should inform themselves about and decision-making on the well-being of Population Action International nario alone. There are immeasurable consider how their lifestyles and their their communities and of the world reproductive health possibilities for unexpected demo- political choices influence native as a whole. graphic changes, even in the regions species and ecosystems. Only couples and individuals can services to those who where up to now there has been little Personal lifestyles and everyday choices decide when and how often to have chil- improvement in women’s status and affect biological diversity in an increas- dren. And in general, the social and eco- little decline in fertility rates. request them. ingly populous world. Both are important nomic realities of personal and family Conservationists can learn more about forms of expression in democratic soci- life tend to play the strongest roles in human population and fertility dynamics eties and in market economies. most couples’ reproductive decision-mak- and promote that understanding in their These choices are most effective when ing. But collectively such decisions will publications. When using the United they transmit strong signals—messages affect the future of biodiversity and the Nations population projections, scientists about preferences, acceptable standards quality of life of all future human beings. and educators should employ the range of and willingness to pay—to those control- Governments, for their part, should future population possibilities—the UN ling the distribution of goods and servic- encourage environmental and population high and low scenarios—rather than the es. For example, paying a little more for education, and promote the diffusion of medium scenario. This approach commu- products like habitat-friendly shade- information that leads to responsible nicates the uncertainties and possibilities grown coffee, paper produced through reproductive decision-making. No Biosphere Like Home

hen human population growth cial ecosystem, demonstrating its poten- Carbon dioxide (CO2) levels shot up dra- induces scarcity, according to one tial, dealing with its challenges and doc- matically as microbes in Biosphere 2’s Wline of economic reasoning, the umenting changes in its environment. rich garden soils quickly consumed the price of the scarce resource rises. That, it From its early stages the project drew system’s oxygen and released above-nor- can be argued, spurs innovation and frequent coverage from the science news mal quantities of CO2. Less than 18 invention, which stimulates production media. As time wore on it became appar- months after the biospherians sealed and provides reasonably-priced substi- ent that even with considerable financial themselves into the enclosure, the sys- tutes. Thus, scarcity-induced problems resources at their disposal, scientists and tem’s atmospheric oxygen concentration are eliminated, making resources once engineers are still a long way from repli- dropped by nearly one-half. again affordable. This reasoning may well cating systems that successfully deliver Air temperatures, however, climbed. “. . . there is still apply to certain non-renewable resources the services that Earth’s ecosystems offer Vines introduced to absorb CO2 grew like metals or energy sources. It is fool- free of charge. explosively, blocking light and threaten- no demonstrated hardy thinking, however, when assumed Trying to maintain Biosphere 2’s bio- ing Biosphere 2’s crops and other plants. to predict the response of non-human diversity may have been the project’s Trees stressed by high CO2 concentrations life and complex ecosystem relationships. biggest challenge. Although the enclo- dropped branches too brittle to hold alternative to If proof is needed, there is Biosphere 2. sure was over-stocked with species to their own weight. With natural processes A fully enclosed, live-in ecosystem see which could survive the competition, spiraling out of control, the researchers maintaining the located in Arizona, Biosphere 2 occupies more extinctions occurred than scientists abandoned the illusion that Biosphere 2 73 Nature’s Place 1.3 hectares and has its own atmosphere, had anticipated. Of the system’s 25 was truly isolated from Biosphere 1—and viability of Earth.” ponds, plants and animal life. The proj- species of vertebrates, 19 went extinct, pumped in outside oxygen to sustain the ect was engineered to provide data that as did most of its insect species. With human occupants within. could someday make it possible to oper- most competitors and predators gone, In summing up the lessons learned ate the life support systems needed for ants seemed to thrive, along with cock- from the project, ecologists Joel Cohen long-term space travel. A further point roaches and katydids. All of the enclo- and David Tilman concluded that “there was to help scientists learn more about sure’s pollinators became extinct, leaving is still no demonstrated alternative to life-sustaining processes on what was many of the plant species without a maintaining the viability of Earth.”2 dubbed “Biosphere 1”—the living means to successfully reproduce. Earth—and to provide insight into eco- Biosphere 2’s aquatic and marine commu- References logically sound agriculture and technolo- nities underwent comparable changes.2 1. M. Nelson, “Letters: Biospherian Viewpoints,” gy.1 The enclosure cost an estimated The most immediately hazardous Science 275 (1996). $200 million to design and construct. problem involved the ecosystem’s carbon 2. J.E. Cohen and D. Tilman, Science 274 (1996): 1150-1151. From 1991 to 1993, eight “biospheri- cycle, which came close to threatening ans” lived and worked within the artifi- the human lives that breathed its air. Demographic Hope in large part from policies and programs References for Biodiversity supported decades earlier. Voluntary 1. P.H. Raven, “Our Diminishing Tropical family planning programs were key. But Forests,” in Biodiversity, ed. E.O. Wilson At the dawn of the 21st century, we find so were other policies that increased the and F.M. Peter (Washington, DC: —and who would have predicted it?— National Academy Press, 1986), 119-122, demand for these programs—especially pp. 120-121. that human population growth is among policies that put more girls into class- 2. Consortium for Earth Sciences the most resolvable of all of the major rooms, and opened employment oppor- Information Network, “Environmental global trends that now threaten biodiver- tunities for women.6 Treaties and Resource Indicators,” Data sity. A recent study estimated that, Base (New York: Columbia University, The future could see a continuation 1999), http://sedac.ciesin.org/prod/char- The future could see a today, the population of the developing of today’s impressive decline in fertili- lotte (last accessed, Aug. 30, 1999). world is around 700 million smaller than ty—if citizens and the governments that 3. Alan Guttmacher Institute, Sharing continuation of today’s it would have been without organized represent them support and fund the Responsibility: Women, Society and Abortion Worldwide (New York: AGI, family planning programs. That figure, policies and programs that make such representing unintended pregnancies 1999). impressive decline in change possible. Decisions made today 4. R. Engelman, Plan and Conserve: A that otherwise would have contributed will have an enormous influence on the Source Book on Linking Population and to population growth were it not for the future size of world population. No Environmental Services in Communities fertility—if citizens and (Washington, DC: Population Action availability of effective contraception, is prognosticator can predict how much of projected to reach 3.1 billion by 2050— International, 1998). a difference a stabilized or even tem- 5. J. Bongaarts, W.P. Mauldin, and J.F. the governments that assuming continued investments in porarily declining world population will Phillips, “The Demographic Impact of these programs.5 make to the survival of the uncountable Family Planning Programs,” Studies in represent them support The past 30 years have seen enor- trillions of beings that accompany us on Family Planning 21, 6 (1990): 299-310. 74 mous progress toward providing univer- 6. A.O. Tsui, “Family planning programs in this living planet. But the difference Asia: Approaching a Half-Century of Population Action International sal access to family planning services, as and fund the policies and could hardly be small. And we humans Effort,” Asia-Pacific Population Research called for in the Cairo Programme of ourselves—simultaneously the threat to, Reports, 8 (Honolulu: East-West Center, Action. There is still a long distance to and the caretakers of, earthly life—will 1996); J. Bongaarts, “Demographic programs that make such go. More than 100 million married Consequences of Declining Fertility,” be among the greatest beneficiaries. Science 282 (1998): 419-420. women would like to space and limit change possible. childbirth but lack access to the means to accomplish these goals.3 Fertility rates are not descending “on their own,” in apparently spontaneous response to economic change. The investment and hard work of govern- ments—those of developing countries as well as industrialized donor nations— and non-governmental organizations have made a difference. Studies of Southeast Asian nations suggest that today’s population growth rates resulted AppendicesAppendices

Appendix 1: Data Sources and Methodology a Demographic estimates and projections tion, endangered, and critically endangered. In trend is described by a curve generated by the the early 1990s, IUCN’s Species Survival Commission modified exponential function For past estimates and future population projec- standardized a series of methods that scientists S = cA-z tions, this publication uses data from the United now use to determine the category into which a where S is the number of original species Nations 1998 medium-range projections, which species under study is appropriately fit.3 remaining, c is a constant and z controls the estimate past populations at 5-year intervals from Readers in the United States should be care- shape of the curve. The z-value ranges between 1950 to 1995, and project from 2000 to 2050.1 ful not to confuse IUCN’s conservation status 0.15 and 0.35 over most of the research that has The UN long-range projections, which project categories with those established in the been conducted on this topic. There is a growing population for India, China, and the world’s Endangered Species Act and used by the U.S. 2 consensus that 0.25 is a good approximation for 75 regions are used for senarios out to 2150. Sub- Fish and Wildlife Service. In the United States, the value of the exponent z in most cases.4 national estimates of population density, used in unlike in the IUCN system, threatened and Nature’s Place the global biodiversity hotspot analysis, were endangered remain separate categories. obtained using geographic information systems d Estimating body weights of data. Methods employed in this analysis are out- IUCN (which retains the acronym from its human and livestock populations lined in section h of this appendix. former name, the International Union for the To estimate the total mass of humans, we began Conservation of Nature) is an international body with age-specific expected body weights b Threatened species (conservation status) headquartered in Gland, Switzerland, that brings described by the National Research Council,5 together over 900 governmental and non-govern- Population Action International and most envi- averaged for males and females, and fit a poly- mental organizations. These embrace more than 2 ronmental organizations recognize the IUCN Red nomial curve to this curve (r = 0.99). We 12,000 scientists from 139 countries concerned List as the principal authority on the conservation reduced the age-related weights by 20 percent to with environmental conservation, management, status of known species. Featured on the Red List account for lower average weights in developing regulation and protection. This report uses IUCN are species that biologists, working in conjunction countries. Then, average body weight in kilo- as its principal source for conservation status, with the IUCN–World Conservation Union, have grams (BW) for each age group is: scientific names, and for the spelling of common determined to be threatened with extinction. BW = 0.8(0.0006[AGE]3 - 0.0949[AGE]2 names of species. These are species believed to be nearing extinc- + 4.6361[AGE] + 1.9325), where AGE is the median age for each 5-year age tion or declining rapidly. There are three degrees c The species-area relationship of threatened status in IUCN’s system (listed from category. For age category 80+, AGE was set to least to most threatened): vulnerable to extinc- Over time, the number of original species tends 80. To estimate global human body weight we to decrease with the loss of habitat area. This estimated the average for each 5-year category, multiplied by the number in that age plants and animals. A species was g Geographic information Hotspot land area was calculated category, and then summed for all age counted as being likely not to incur ele- systems (GIS) data layers using Spatial Analyst and CI’s hotspot categories in the world population. vated risks of extinction due to the con- Spatial population density data are layer. Spatial Analyst provided the per- For domestic animal species, we tinued proliferation of human-dominat- obtained from the Gridded Population centage of each country occupied by the used adult weights from various ed ecosystems if the species was identi- of the World, 1995, published by the hotspot. Data from the UN Food and sources, and used the median weight fied with a human-made structure, a National Center for Global Geographic Agricultural Organization (in World 6 from the range listed. We assumed that land-use type, or a domestic species. Analysis (NCGIA), University of California, Resources, World Resources Institute, in species living more than two years, Key words included: city, suburb, road- Santa Barbara, USA. These data can be 1997) were used as the source for most one-year-olds attain one-third of adult side, mine, waste place, garbage dump, downloaded from Columbia University’s country areas. Total land areas for weight, two-year-olds two-thirds of building, farm, livestock, crop or gar- Center for International Earth Science Anguilla, Federated States of Micronesia, adult weight, and from three years den. Because large predators are effec- Information Network (CIESIN) Website, Marshall Islands, Mayotte, Monaco, onward they attained adult body tively eradicated to reduce losses to at the following address: http://www. Montenegro, Northern Mariana Islands, weight. For species living two years, livestock, the method likely overesti- ciesin.org/datasets/gpw/globldem.doc. Palau, Pitcairn Islands, and the West Bank we assumed two-thirds weight for one- mates the number of large predators html.9 The year 1995 is the basis for all were taken from data provided by The year-olds, and full weight thereafter. that will survive in human-dominated population density mapping in this CIA World Factbook, 1997. ecosystems. publication. Average hotspot population density e Estimating population For example, in three guides to North Hotspots and major tropical wilder- was calculated using Spatial Analyst densities of mammals American birds, descriptions of about ness boundaries were created and digi- applied to NCGIA’s Gridded Population Robert Henry Peters used numerous 25 to 35 species (roughly 5 percent of tized by Conservation International (CI). of the World, 1995. As a preliminary studies of mammals to derive statistical the 650 birds) mention cities, lawns, CI continues to identify hotspots from step to calculating average hotspot models that relate adult body weight to and buildings or farm fields, crops and among the most biodiverse regions of growth rates, population density was livestock. Using the same method, 76 the observed abundance of these ani- the world, and to modify boundaries of calculated for the total hotspot, the por- mals in the wild. Peters’ work predicts about 15 percent of listed European tion of each country within the hotspot. Population Action International the hotspots that it presently recognizes. that the density of mammalian species’ birds fall in this category. For flowering Current forest cover and original for- In cases where sub-national population within their home ranges, if living in plants, around 10 percent mention est cover, used in the Madagascar case growth rate data were available, popu- an undisturbed condition, should vary human-dominated ecosystems. Some study, were mapped from various coun- lation density was determined for sub- according to the following relationships:7 70 percent of these are weedy exotic try sources by the World Conservation national units (provinces, states). species. In guides of North American Hotspot population growth rates Population Density of Carnivores Monitoring Centre.10 plants (around 380 species) some 15 were estimated by partitioning hotspots = 15 x [Average Body Weight] - 1.16 percent show similar references. For into their respective countries and Population Density of Herbivores mammals, however, more than half of h Biodiversity hotspots and provinces within countries, and calcu- - = 103 x [Average Body Weight] 0.93 these references are for bats, most of human population analysis lating a population-weighted average of which roost in buildings and are being Geographical information systems map- growth rates for all of the portions. f Species in human-dominated exterminated because of this habit. ping and analysis was conducted using Where hotspots covered only portions ecosystems Also in that number are predators that ArcView software, a product of Earth of countries, sub-national data (provin- To produce rough estimates of the occasionally kill livestock, some of System Resources, Inc. (ESRI). Population cial or state data) were used when number of species that presently show which have been actively hunted with densities of hotspots and major tropical available to weight the portions within signs of co-existing with humans in some success. Omitting these groups wilderness areas were determined using those sub-national units. In this publi- human-dominated ecosystems, we sur- provides a more realistic estimate of Spatial Analyst, an application devel- cation sub-national population growth veyed several guides to well-studied around 5 percent.8 oped for ArcView workstations by ESRI. rates were applied to parts of Argentina, Australia, Brazil, Bolivia, Colombia, China, Ecuador, France, India, Indonesia, References j Sources for sub-national census data Mexico, Panama, Peru, South Africa, 1. UN Population Division, World Population Argentina: Instituto Nacional de Estadística y Censos (INDEC), Spain, Turkey, the United States, and Prospects: The 1998 Revision (New York: Anuario Estadistico 1998, (Buenos Aires: INDEC, 1998), Venezuela in order to determine aver- United Nations, 1998). 2. UN Population Division, World Population http://www.indec.mecon.gov.ar/default.htm, (last age population growth rates for biodi- Projections to 2150, (New York: United accessed: Nov. 29, 1999); 1997 Britannica Book of the versity hotspots or major tropical Nations, 1998). Year (London: Encyclopaedia Britannica, 1997). wilderness areas. 3. IUCN Red List of Threatened Animals (Gland: IUCN-World Conservation Union, 1996); Australia: Australian Bureau of Statistics (ABS),”ABS Statsite,” i Human population between IUCN Red List of Threatened Plants (Gland: Australian Demographic Statistics, Catalogue No. 3101.0, the tropics IUCN-World Conservation Union, 1998). March Quarter 1998 (Canberra: ABS, 1998), 4. N. Myers, “Global Biodiversity II: Losses,” in http://www.statistics.gov.au, (last accessed: Dec. 4, There were several methodological Principles of Conservation Biology, ed. G. K. 1998); 1997 Britannica Book of the Year (London: steps used in estimating population Meffe and C.R. Caroll (Sunderland, MA.: Encyclopaedia Britannica, 1997). within the tropics, the land situated Sinauer, 1997), 110-139. 5. NRC, “Recommended Dietary Allowances,” between the Tropics of Cancer and Brazil: Instituto Brasileiro de Geografia e Estatistica (IBGE), 10th Ed. (Washington, DC: National Research “Diretoria de Pesquisas, Population Census 1991,” Capricorn. First, an estimate was made Council, 1989). of the 1995 tropical population. Where 6. B. Grzimek (ed.), Grzimek’s Animal Life (Brasilia: IBGE, 1991), http://www.ibge.gov.br (last countries were wholly within the trop- Encyclopedia., Vol. 10 - 14 (New York: Van accessed: Nov. 29, 1999). ics, national populations were obtained Nostrand Reinhold, 1972-75); National China: China National Statistics Bureau, “China Cities,” (Beijing: from the UN Population Division, and Zoological Park, “Animal Facts,” Data Base, http://www.fonz.org/animals/animalfacts.ht China Today, 1999), http://www.chinatoday.com/ summed. To estimate contributions to m (last accessed, August 30, 1999); various city/a.htm, (last accessed: Jan. 20, 1999); People’s this sum from countries straddling the sources. Republic of China, Atlas of the People’s Republic of China, tropics, sub-national tropical popula- 7. R.H. Peters, The Ecological Implications of ed. Sun Xiudong (Beijing: China Cartographic Publishing 77 tions were estimated using the 1995 Body Size (New York: Cambridge Univ. Press,

House, 1989). Nature’s Place World Population Density GIS layer. 1983). 8. C.S. Robbins, B. Bruun, and H. S. Zim, A Colombia: Departamento Administrivo Nacional de Estadística A somewhat different method was Guide to Field Identification: Birds of North (DANE), “Censo de Población y Vivienda de 1993,” used to estimate for past years (1950 to America (New York: Golden, 1983); R.T. (Bogotá: DANE, 1993), http://www.dane.gov.co/, (last 1990, at 5 year intervals). For countries Peterson, G. Mountfort, and P.A.D. Hollom, A accessed: Jan. 20, 1999); DANE, XV Censo Nacional de wholly within the tropics, again the UN Field Guide to the Birds of Britain and Europe, Poblacion y IV de Vivienda: Colombia, vol. I (Bogotá: Population Division’s estimates were The Peterson field guide series, 8 (Boston: Houghton Mifflin, 1966); R.T. Peterson and DANE, 1986). used and summed. Because GIS sub- M. McKenny, A Field Guide to Wildflowers: Ecuador: Instituto Nacional Estadística y Censos (INEC), national population density data does Northeastern and Northcentral North America not exist prior to 1995, it was assumed (Boston: Houghton Mifflin, 1968); W.H. Burt “Proyecciones de la Población Total por Años Calendario that the percentage of the population in and R.P. Grossenheider, A Field Guide to the Según Provincias: Périodo 1990-2000,” (Quito: INEC, no those sub-national areas within each Mammals: North America North of Mexico, date), http://www4.inec.gov.ec/master.htm, (last 3rd ed. (New York: Houghton Mifflin, 1980). country that straddles a tropic (such as accessed: Nov. 29, 1999); 1997 Britannica Book of the 9. W. Tobler, U. Deichmann, J. Gottsegen, and Year (London: Encyclopaedia Britannica, 1997). Australia, China, India, Mexico and K. Maloy, “The Global Demography Project,” others) was identical to the 1995 per- Tech. Report, 95-6 (Santa Barbara: National India: National Statistical Institute of India (NSII), “Population centage. This source of inaccuracy Center for Geographic Information Analysis, Statistics, India 1991: Population Data,” (New Delhi: makes this a rough estimate, but one Univ. of California, Santa Barbara, 1995). NSII, no date), 10.World Conservation Monitoring Centre, “A that should be accurate to within a http://www.censusindia.net/cendat/sub.html, (last Global Overview of Forest Conservation,” CD- hundred million people. ROM (Cambridge, U.K.: WCMC, 1997). accessed: Dec. 8, 1998). Indonesia: UN Statistics Division, “Popmap,” CD ROM, INT/96/P74/WWW (New York: UN, 1998). Mexico: Instituto Nacional de Estadística, Geografía e Informática (INEGI), ”Estadísticas Demográficas y Socioeconómicas de México,” (Mexico: INEGI, 1997). Peru: Instituto Nacional de Estadística e Informática (INEI), “IX Censo Nacional de Población y IV de Vivienda, 1993” (Lima: INEI, 1995), http://www.inei.gob.pe/, (last accessed: Feb. 9, 1999). South Africa: Statistics South Africa (SSA), “The People of South Africa: Census 1996,” (Pretoria: SSA, 1998), http://www.statssa.gov.za/census96/HTML/DEFAULT. HTM, (last accessed: Nov. 13, 1998). Spain: Instituto Nacional de Estadística (INE), “España en cifres,” (Madrid: INE, 1997), http://www.ine.ex/htdocs/espcif/espcifin.htm, (last accessed: Feb. 11, 1999). Turkey: State Institute of Statistics, (Ankara: Prime Ministry 78 of Turkey, 1998), http://www.die.gov.tr, (last

Population Action International accessed, Nov. 29, 1999); 1997 Britannica Book of the Year (London: Encyclopaedia Britannica, 1997). United States: U.S. Bureau of the Census, “State Population Estimates and Demographic Components of Population Change: July 1, 1997 to July 1, 1998,” Doc. ST-97-1 (Washington, DC: U.S. Dept. of Commerce, 1997), http://www.census.gov/popula- tion/www/estimates/statepop.html, (last accessed: June 22, 1999). Venezuela: Oficina Central de Estadística y Informática (OCEI), “XII Censo de población y vivienda, 1990,” (Caracas: OCEI, no date), http://www.ocei.gov.ve, (last accessed: March 9, 1999); 1997 Britannica Book of the Year (London: Encyclopaedia Britannica, 1997). Appendix 2: Figures and Their Sources

Figure 1: Possibilities in the Figure 6: Human Colonization and Figure 12: Human Fertility Change in Figure 18: Limited Alternatives: Demographic Future Associated Species Loss Highly Biodiverse Countries Population Growth and Responses in Source: data from UN Population Division, Source: adapted from J. Diamond, The Source: UN Population Division, World Agriculture and Housing World Population Projections to 2150, (New Third Chimpanzee: The Evolution and Population Prospects: The 1998 Revision Source: Population Action International York: United Nations, 1998). Future of the Human Animal (New York: (New York: United Nations, 1998); list of Figure 19: More People, More Non-Native Harper Collins, 1992). biodiversity countries from R.A. Species Figure 2: Population and Status of the Figure 7: Islands of Nature: Population Mittermeier, P. Robles Gil, and C. Source: adapted from E.H. Rapoport, “The Great Apes Growth and the Isolation of Protected Goettsch Mittermeier, Megadiversity: Process of Plant Colonization in Small Sources: see reference following text Areas Earth’s Biologically Wealthiest Nations Settlements and Large Cities,” in Humans (Mexico, C.F.: Cemex, 1997). Figure 3: Counting Earth’s Species Source: R.S. Reid, L. Kruska, U. as Components of Ecosystems, ed. M.J. Source: adapted from N.E. Stork, Deichmann, P.K. Thornton, and S.G.A. Figure 13: World Population: McDonnell and S.T. A. Pickett (New York: “Measuring Global Biodiversity and Its Leak, “Human Population Growth and Past and Projected Springer-Verlag, 1993), 190-207. Decline,” in Biodiversity II: Understanding the Extinction of the Tsetse Fly,” (unpub- Source: UN Population Division, World Figure 20: Nitrogen Pollution and and Protecting Our Biological Resources, lished manuscript, 1999). Population Projections to 2150, (New Population Density ed. M.L. Reaka-Kudla, D.E. Wilson, and Figure 8: Domesticated Demographics: York: United Nations, 1998). Source: J.J. Cole and others, “Nitrogen E.O. Wilson (Washington, DC: Joseph the Growth of Domesticated Animals Figure 14: Population in the Loading of Rivers as a Human-Driven Henry Press, 1997), 41-68. Source: data from FAO STAT, CD-ROM Industrialized Countries Process,” in Humans as Components of (Rome: Food and Agriculture Source: UN Population Division, World Ecosystems, ed. M.J. McDonnell and Figure 4: Species Numbers Organization, 1998). Population Prospects: The 1998 Revision S.T.A. Pickett (New York: Springer-Verlag, and Habitat Area 79

Source: adapted from A. Dobson, Figure 9: Newly Emerging Diseases (New York: United Nations, 1998). 1993), 141-162. Nature’s Place Conservation and Biodiversity (New York: Source: D. Pimentel and others, “Ecology Figure 15: Understanding Momentum Figure 21: People and Property Values Scientific American Library, 1996), p. 66. of Increasing Disease,” Bioscience 48, 10 Source: UN Population Division, World Source: data from U.S. Census Bureau, (1998): 817-826. Population Prospects: The 1998 Revision “Taxable Property Values: Assessed Figure 5: Centers of Crop and (New York: United Nations, 1998). Valuations for Local General Property Livestock Origin Figure 10: Population in the Tropics Source: estimates by Population Action Figure 16: Trends in Extinction Taxation,” GC92, Vol. 2 (Washington, DC: Source: N.I. Vavilov, “The Origin, U.S. Dept. of Commerce, 1996). Variation, Immunity and Breeding of International; data from GIS analysis of Source: data from World Conservation Cultivated Plants,” transl. K.S. Chester, World Population Density, 1995, GIS Data Monitoring Centre, Global Biodiversity: Figure 22: Population Density in the Chronica Botanica, 13, 1-6 (1949-50); Layer (CIESIN/UNEP, New York/Sioux Status of the Earth’s Living Resources Biodiversity Hotspots N.W. Simmonds, Principles of Crop Falls, SD, 1997). (London: Chapman & Hall, 1992). Source: Population Action International, Improvement (New York: Longman, Figure 11: Expected Population Densities Figure 17: Threats to Species data from GIS analysis of World 1979); N. Myers, The Wild Supermarket: of Mammals Source: (A.) Population Action Population Density, 1995, GIS Data Layer the Importance of Biological Diversity to Source: adapted from equations pub- International; (B.) D.S. Wilcove and oth- (NCGIA, University of California, Santa Food Security (Gland: World-Wide Fund lished in R.M. Peters, The Ecological ers, “Quantifying Threats to Imperiled Barbara, 1994). for Nature, 1990). Implications of Body Size (New York: Species in the United States,” Bioscience Figure 23: Population Growth in the Cambridge Univ. Press, 1983). 48, 8 (1998): 607-615. Biodiversity Hotspots Source: Population Action International, synthesized from various sources, see Appendix 1h. Selected Recent Publications From Population Action International

Population & Environment Studies Population Policy Ship to: Research Forest Futures: Population, Consumption and Wood Name Resources (NEW) Africa’s Population Examines impact of shrinking forest cover worldwide Challenge: Accelerating Organization on resources and human quality of life. Contains Progress in Reproductive Street Address insert chart ranking 157 countries by per capita forest Health availability in 1980, 1995, and 2025. (1999. 68pp. Highlights the progress City, State/Province, Zip/Postal Code, Country English. $9.00) Africa has made in expand- ing access to reproductive Telephone Email Profiles in Carbon: An Update on Population, health care and the chal- Please make checks or money orders in U.S. dollars, drawn on a Consumption and Carbon Dioxide Emissions lenges countries face to pro- U.S. bank, payable to: Population Action International Highlights neglected linkages between population and vide quality services for all 1300 19th Street, NW climate by chronicling CO2 emissions from 1950 to their people. (1998. 88 pp. 2nd Floor 1995. Includes charts on 145 countries by 1995 per English, French. $9.00) Washington, DC 20036 USA capita emissions, and 180 individual country charts. For bulk orders, contact Carolyn Ross: (1998. 40 pp. English. $5.00) Educating Girls: Gender Phone: 202-659-1833 Gaps and Gains Fax: 202-293-1795 Sustaining Water, Easing Scarcity: A Second Update Wall chart ranks 132 coun- Email: [email protected] PAI revision of estimates and projections of the tries by difference between 80 Order publications on-line at http://www.populationaction.org amount of fresh water available to each person in school enrollment rates for All domestic orders are postpaid. Population Action International most countries from the present to 2050. Based on girls and boys, showing All orders to be shipped outside the USA will be charged postage. 1996 UN population projections, which reflect a slow- where girls lag furthest Publications are available in limited quantities, at no charge, to residents of ing of population growth. (1997. 20 pp. English. behind boys. Illustrates the developing countries. $5.00) link between education and Order Form teen birthrates and offers Description Quantity Language Item Price Total Price Plan and Conserve: A Source Book on Linking strategies for increasing Population and Environmental Services in girls’ access to education. Communities Eighth in PAI’s Report Card Unique guide summarizing the history of integration series. (1998. Wall chart. of population and environment programs. Profiles 42 English, French, Spanish. community projects. (1998. 112 pp. English. $9.00) $6.00)

Forging the Link: Emerging Accounts of Population TOTAL and Environment Work in Communities (NEW) PAYMENT BY: ❒ VISA ❒ MASTER CHARGE ❒ CHECK Examines feasibility of integrating reproductive health and environmental sustainability into the same devel- Card Number:❒❒❒❒❒❒❒❒❒❒❒❒❒❒❒❒ opment project. Summarizes efforts of last 25 years Exp. Date ❒❒ ❒❒ Signature and explores benefits and challenges of approach. (1999. 56 pp. English. $9.00) Please copy form and send with payment Population Action International

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Officers Directors The Council Chair Vincent Anku Joseph D. Tydings, Chair Constance Spahn Vicki-Ann E. Assevero C. Payne Lucas, Vice Chair Vice Chairs Anthony C. Beilenson Robert Fearey, Secretary William H. Draper, III Pouru P. Bhiwandi Norman E. Borlaug Victoria P. Sant Marion M. Dawson Carr Sharon L. Camp Chair Emeritus William Clark, Jr. A.W. Clausen Robin Chandler Duke Bill Green Barber B. Conable Kaval Gulhati Henry H. Fowler Treasurer Yolanda Richardson Julia J. Henderson Scott M. Spangler Allan Rosenfield Lawrence R. Kegan Secretary Fred T. Sai Edwin M. Martin Phyllis Tilson Piotrow Isabel V. Sawhill Robert S. McNamara President Timothy L. Towell Wendy B. Morgan Amy Coen Joseph C. Wheeler Thomas H. Roberts, Jr. William D. Zabel Elmer Boyd Staats

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