Systematics and the Conservation of Biological
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r- rden R. I. Vane-Wright 2 rd, J. Piesman & M. D. Corwin. SYSTEMATICS AND THE is on Nantucket Island, USA: or, lxodes (Ixodes) dammini, n. CONSERVATION OF J. Med. Entomol. 15: 218-234. BIOLOGICAL DIVERSITY' ather, S. I. Moore, M. L. Wilson Incompetence of deer as reser- ase spirochete. Amer. J. Trop. ABSTRACT mier & J. A. Rawlings. 1991. from arthropods col- •urgdofen This paper concerns the role of systematics in efforts to conserve biological diversity. Biodiversity is seen both as Trop. Med. Hyg. 44:469-474. J. an interdisciplinary science (involving ecology and population biology as well as systematics), and as a socio-political Lain, J. H. Oliver, Jr., J. Piesman activity (because of the strongly anthropocentric focus of the Convention on Biological Diversity). Systematics has a . Investigation of the validity of number of key roles to play, especially with respect to maximizing our limited and fragmentary knowledge of biology us- s dammini (Acari: Ixodidae) through the predictive power of natural classification, and in helping to set priorities for conservation when, as is . Acad. Sci. U.S.A. 90: 10221— inevitably the case, resources are limited. After examining ways in which systematists must support the growing needs of society to know more about the Earth's biota, it is concluded that, because of their unique insights into the subject, rsic, U. B. Gobel, B. Graf, S. Jaur- systematists have an equally strong responsibility to take an active lead in many of the issues relating to the study, hwab & G. Zumstein. 1992. An use, and conservation of biological diversity. em for Borrelia burgdmfen based noclonal antibodies and OspA se- lin. Microbiol. 31: 340-350. Dan Janzen (1993) has asked "What does trop- itarianism" (Porritt, 1994) is the best strategy is ical society want from the taxonomist?" In relation open to debate (e.g., Allen & Edwards, 1995; to the urgent need to know more about biological Oates, 1995), but this is where most of the force diversity, this question raises further issues—no- behind national and international conservation ef- tably, is biodiversity only really important in the forts is now located. The Global Environment Fa- tropics, and does taxonomy only have a supporting cility (Glowka et al., 1994), the interim financial role in the study of biodiversity? Here I will discuss mechanism of the Convention (currently adminis- all three questions, taking the view that taxono- tered by the World Bank), is the largest single mists, and systematists in general, need to be source of funding ever made available for work on proactive as well as supportive in their work. biodiversity—a funding source which systematists seem surprisingly slow to exploit. As Robert May SHOULD SYSTEMATISTS TAKE A LEAD IN THE (1990) has observed, "Without taxonomy to give STUDY OF BIODIVERSITY? shape to the bricks, and systematics to tell us how to put them together, the house of biological science The subtitle of Global Biodiversity Strategy (Reid is a meaningless jumble." If systematics provides et al., 1992), one of the key documents produced the foundation of our understanding and ability to before the 1992 UNCED conference, is "Guidelines communicate about biological diversity, what role for action to save, study, and use Earth's biotic should systematists seek to play in the study, use. wealth sustainably and equitably." The earlier Car- and conservation of the Earth's biotic wealth? ing for the Earth (IUCN/UNEP/WWF, 1991) has the subtitle "A strategy for sustainable living." The WHAT IS B1ODIVERSITY? primary objectives of the Convention on Biological Diversity are "the conservation of biological diver- An impression can readily be formed from much sity ... the sustainable use of its components ... of the modern bioscience literature that the study and the fair and equitable sharing of the benefits of biological diversity is the preserve, not of sys- arising from the use of genetic resources" (Glowka tematics, but of ecology. The study of diversity rests et al., 1994). Thus many of these goals are un- neither with one nor the other, but with both. Bio- ashamedly anthropocentric and primarily con- diversity exists at the interface of pattern and pro- cerned with conservation for human benefit, rather cess, as for example in the twin hierarchy envis- than preservation of wildlife for its own sake. aged by Eldredge and Salthe (1984; Table 1), in Whether or not this "rampant, unapologetic util- phylogenetics and population genetics (the distinc- ' My sincere thanks are due to Peter Raven, Jay Savage, and Mick Richardson for the invitation to attend the 41st Annual Systematics Symposium. It was a delight to be in such stimulating company, meet many new colleagues, and have an opportunity to see firsthand the great achievements of the Missouri Botanical Garden. I am grateful to Dave Hollis, Scott Miller, Nigel Stork, and Paul Williams for constructive comments on the manuscript. Biogeography and Conservation Laboratory, The Natural History Museum, Cromwell Road, London SW7 5BD, U.K. ANN. MISSOURI BOT. GARD. 83: 47-57. 1996. ■•■•••■■•• tr" 48 Annals of the Missouri Botanical Garden Table 1. The twin biological hierarchy (based on El- dissimilarity between species, and basic uncertain- dredge & Salthe, 1984). ties about how to delimit the number of genes even in well-known organisms, compound any attempt to Genealogical hierarchy Ecological hierarchy estimate the protean diversity that occurs at the [pattern] [process] genetic level. Undeterred, Wilson (1992) has esti- Codons Enzymes 7 nucleotide mated something in the order of 10' Genes Cells pairs as specifying the diversity among species. to- Organisms 8 Organisms gether with more than 10' gene combinations po- [individuation] [physiological function] tentially available per typical species. Taxonomists Demes Populations might seem like chemists with a knowledge of 10 Species Local ecosystems Monophyletic taxa Biotic regions elements from the Periodic Table, while geneticists All life Entire biosphere might be compared to physicists trying to under- stand the Universe from the behavior of just a sin- gle fundamental particle. Is our ignorance of the biosphere really so extreme? tion between phylogenetic and tokogenetic relation- In 1973 a mealybug was discovered attacking ships: Hennig, 1966), and in historical versus eco- cassava in Africa. By the end of 1989 this pest was logical biogeography (Myers & Giller, 1988). causing massive crop losses throughout the African Olivier Rieppel (1988) has discussed in depth a tropics. Initial attempts to find a natural biocontrol number of the scientific and philosophical issues of agent failed, until it was realized that the meals bug the pattern versus process debate. He observed that was part of an undescribed species complex. and the analysis of pattern and process represents dif- that it only occurred naturally in the southern Neo- ferent and incompatible "ways of seeing," as "the tropics (Cox & Williams, 1981). An appropriate en- first emphasises discontinuity, while the other is cyrtid wasp was then found, tested, and introduced based on the principle of continuity." The two are into Africa. The wasp has now spread over more complementary because pattern analysis offers the than 12 million km= and gives effective control of only guide to common ancestry, and so gives direc- the mealybug throughout its African range. with an tion to the analysis of process, while process anal- annual cost benefit estimated at $200.000.000 ysis is the only way of giving pattern a causal ex- (Herren & Neuenschwander. 1991). planation. He finally concluded, given we have This example, involving a new pest and an different ways of seeing biology, that we should ac- equally unknown biocontrol agent. tells us some- cept that each has its merits and faults, and that thing special about the nature of our ignorance. Bi- each is incomplete by itself. Being complementary, ology has to deal with a staggering number of spe- we should make use of both approaches to get as cifics—there are thousands of mealybugs. and tens complete a picture of biology as possible (Rieppel, of thousands of encyrtid wasps. To solve the prob- 1988, esp. 170-171). Because of this intimate in- lem, entomologists had to find out precisely which terrelationship, it is essential that systematists work mealybug they were dealing with, locate this spe- together with ecologists and population biologists to cies in its natural habitat, and discover precisely develop a fuller understanding of biological diver- which of all those wasps was one that attacked it. sity, including its potential uses—and, most ur- The only reason this could be done quickly is be- gently, to develop more effective strategies for its cause the existing classification of bugs and wasps, conservation. however incomplete, is sufficient to form a valid basis for prediction. Once the mealybug had been SYSTEMATICS AND THE USE OF BIODIVERSITY accurately located in the system, it was possible to Current estimates of the number of extant spe- predict its geographical origin, and then what sort cies of organisms vary from 3 to 100 million; Ham- of insect to look out for as a natural biocontrol mond (1992) gave a carefully considered estimate agent. Our detailed knowledge of the biology of all of 12.5 million, but confidence limits on such fig- these myriad species inevitably lags behind our ures are incalculable. There is greater agreement knowledge of their classification, but the natural about the number of species