DOCSLIB.ORG

Gene Flow in the Environment – Genetic Pollution? G.R

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Gene Flow in the Environment – Genetic Pollution? G.R Gene flow in the environment Gene flow in the environment – genetic pollution? G.R. Squire, N. Augustin, J. Bown1, J.W. Crawford, G. Dunlop, J. Graham, J.R. Hillman, B. Marshall, D. Marshall, G. Ramsay, D.J. Robinson, J. Russell, C. Thompson & G. Wright iological invasions have had profound effects on affect plants and animals, injure us? Will crops in gen- Bhuman society from the earliest times. The spread eral, and GM ones in particular, reduce even more the of the black death in the Middle Ages, the devasta- biological diversity of arable farmland? Will they con- tions of potato blight, the effects on indigenous taminate other crops, cause more pesticide to be used, species by grey squirrels, dutch elm disease and flat- rather than less as some companies claim? worms have all been seen as detrimental to man or the environment. Others are seen as bringing benefits: An increasing number of people have a stake in the most of our crops evolved elsewhere in the world and debate - pressure groups, farmers, farm advisers, con- many culinary and medicinal herbs were brought to sumers, agrochemical companies and government. Britain by the Romans. Perhaps the greatest invasion Opinions are too often polarised. In this confronta- is the import of vast numbers of exotic plants to gar- tional atmosphere, the need is for clear, independent dens and greenhouses. Ecological invasions are an fact, answers and comment. A part of the debate is intrinsic part of ecology and evolution and we only ethical, but independent research is essential on ques- consider them bad if they impoverish our health, tions that science can legitimately address. This is not livelihood or living conditions. to say that scientists should not be ethical, but that the methods of science can only be applied to answer cer- Recent events brought awareness of a need to be tain types of question through constructing hypothe- knowledgeable and vigilant about where food comes ses and testing them by observation, experiment and from, how it is grown and what it might contain. modelling. It cannot say, for instance, that grey squir- During the 1990s, agriculture and the food chain rels or GM herbicide-tolerant crops are ‘good’ or returned to be daily topics of conversation. In 1998, ‘bad’. The answer depends on your standpoint. Sci- the concern was for genetically modified crops, and ence can, however, define what effect such organisms the term ‘genetic pollution’ came into common usage. are having or might have on wildlife, habitat and There is no place in science for such emotive terms health, and advise government and the public on the but publicly funded science must answer, as far as it risks and hazards. can, the public’s fears with facts and sound interpreta- tion. Invasions are complex biological processes. How do we study them? First there is the movement of plants The questions? Biological science is regularly in the or seeds, and the transfer of genes by pollen. The spotlight. Is habitat being destroyed by land manage- organisms have to find and occupy space and grow in ment practices? Will GM crops escape from fields, their new environment, while the pollen has to find 1University of Abertay, Dundee 45 Gene flow in the environment receptive stigmas and create a new organism. Incom- and interpreting rare events and small numbers. ing plants have to interact for space and resource with Methods and techniques are needed to do three the plants that are already there, and accumulate things: to show that an organism or gene has moved enough mass to reproduce and maintain a stronghold. from one place to another; to measure its effect on the The local environment acts on them and sorts out the existing organisms at that place; and (because these less able. Exchange of genes creates variants that are two can only be done on a small number of the organ- continually re-sorted. The nature of the invaded pop- isms) to build the greater picture from all the available ulation changes from what it was at the beginning. data. The sciences of plant ecology, genetics, zoology, pathology, mathematics and statistics are all put to use The difficulty lies in in this work. Research not the range of interacting only has to break new ground scales. Growth or in each subject but to find death, and exchange of new ways of seaming them genes, occurs through together. direct interactions between individuals. Genetic exchange and detec- The individuals occur tion Advances in knowl- in patches or fragments edge of the genetic code have and the fragments are led to robust techniques for scattered over the land- genetically typing individuals scape. Single fragments and for detecting the move- evolve their own char- ment of genetic material acteristics that fit them from one plant to another. to the local environment. The patches are not inde- Some of the techniques now in use at the Institute1,2 pendent, but potentially connected through the are shown in Figure 1. Each is appropriate for a spe- migration of seed or transfer of pollen. The individu- cific purpose. To confirm geneflow, it is essential to als in distant patches can therefore influence the inter- observe a transfer of genetic material from one indi- actions within any other patch. Clearly, the degree of vidual or group to the progeny of another. Potential connectivity will depend on whether the pollen or receptors and donors need to be genetically typed to seed moves by wind or is carried by insects or other search for distinguishing features in their DNA. Seed animals, and how sexually compatible are the plants in is collected from the potential receptor (mother) the different patches. This system evolves therefore at plants, germinated and the seedlings also genetically scales of both the patch and landscape. This is what typed. The DNA of the mother plant and seedlings makes the study of gene flow and invasions so difficult are then compared. Gene flow has occurred if a partic- and so challenging. Very advanced techniques are ular DNA sequence is found in a seedling but not in being developed and used to examine these exchanges. the mother plant. Further, if the number of potential donors is reasonably small, then some of the tech- New methodologies Movement of seed or genes into niques can trace the plant from which the pollen a fragmented ecosystem usually begins slowly and pro- came. As Figure 1 shows, the approach is being used ceeds gradually. Only when things are well on their to detect and quantify gene flow in plants ranging way are they generally noticed. The crux is detecting from feral brassicas to tropical trees. Microsatellites AFLPs (SSAPs) ISSRs RAPDs Nuclear Chloroplast -Co-dominant Mahogany -Dominant Calycophyllum -Dominant Oilseed rape -Dominant Raspberry Eucalypts Brassicas Grasslands -Single locus Pines -Multi locus Nematodes -Multi locus -Multi locus -Multiallelic Coconut -Biallelic -Biallelic -Biallelic Figure 1 Banding patterns from some genetic technologies, with which it is now possible to assess gene flow and the spatial organisation of genetic variation. The techniques are used at SCRI with the species indicated. 46 Gene flow in the environment The new genetic enabling technologies allow us to do organism enters an ecological assemblage that primar- things that were impossible a few years ago. To answer ily determines its rate of establishment, extinction or most questions, further knowledge is needed of how amplification. Many factors mitigate against the seed or pollen are moved by wind or insects, and ingress of an alien organism, and many invasion whether plants are sexually compatible. This brings in events and many cycles of reproduction are likely to new scales of operation that are influenced by the local be required before it gains a secure place. weather and the flight paths and foraging behaviour of pollinators. Molecular science can contribute to Invasions and population structure In an established knowledge at these scales by helping to define the dis- arable field or wayside patch of ground, perhaps 30 tance over which pollen can move from one plant to weed species cohabit in the soil as dormant seed. another. Among them are likely to be several of the typical, economically damaging, arable weeds: fat hen, Science in this area has recently made major contribu- cleavers, blackgrass, wild oat. Each is at least as capa- tions to the topical and contentious issue of gene ble of exploiting time windows in the weather and transfer from GM crops to wild plants. It has been husbandry as any invading type such as feral oilseed suggested that GM characters will be transferred to rape or feral beet. The existing seedbank species occur weeds giving them resistance to weedkillers and insect in some hierarchy of abundance, and are distributed pests. The flow of genes from some crops to some over space in characteristic ways. Typical abundance wild relatives is possible and will happen if GM crops rankings show a wide range from species that are very are deployed on a large scale. Indeed, crops and weeds dominant (10,000 to 100,000 in a square metre down have exchanged genes since the beginnings of agricul- to plough depth) to those that occur relatively scarcely ture, so there is nothing new in the process itself. So (<1000).Which individuals are dominant depends on far, there are few indications in the UK that crops are the soil, the rotation, the use of herbicide, and other crossing with other species to increase the latter’s abil- factors. The Institute’s unrivalled database on arable ity as a weed. Those crops and wild relatives that are buried seed (seedbanks) is continually probed to 4 most likely to exchange genes in the UK are known in answer questions on arable diversity .
Load more

Recommended publications
  • The Role of Genetic Resources for Food and Agriculture in Climate Change Adaptation and Mitigation
    March 2021 CGRFA/WG-AqGR-3/21/Inf.15 E COMMISSION ON GENETIC RESOURCES FOR FOOD AND AGRICULTURE Item 8 of the Provisional Agenda INTERGOVERNMENTAL TECHNICAL WORKING GROUP ON AQUATIC GENETIC RESOURCES FOR FOOD AND AGRICULTURE Third Session 1 - 3 June 2021 THE ROLE OF GENETIC RESOURCES FOR FOOD AND AGRICULTURE IN CLIMATE CHANGE ADAPTATION AND MITIGATION TABLE OF CONTENTS Paragraphs I. INTRODUCTION ................................................................................................... 1 – 2 II. SCOPING STUDY ON THE ROLE OF GENETIC RESOURCES FOR FOOD AND AGRICULTURE IN ADAPTATION TO AND MITIGATION OF CLIMATE CHANGE ....................................................................................................................... 3 Appendix: Scoping study on the role of genetic resources for food and agriculture in adaptation to and mitigation of climate change NF847 2 CGRFA/WG-AqGR-3/21/Inf.15 I. INTRODUCTION 1. The Commission on Genetic Resources for Food and Agriculture (Commission), at its last session, requested FAO to prepare a scoping study on the role of genetic resources for food and agriculture (GRFA) in adaptation to and mitigation of climate change, including knowledge gaps, taking into account the forthcoming special reports on terrestrial and marine systems by the Intergovernmental Panel on Climate Change (IPCC) and other available relevant sources, including examples from different regions and subsectors.1 2. The Commission further requested its Intergovernmental Technical Working Groups to review the study. II. SCOPING STUDY ON THE ROLE OF GENETIC RESOURCES FOR FOOD AND AGRICULTURE IN ADAPTATION TO AND MITIGATION OF CLIMATE CHANGE 3. The draft text of the scoping study on the role of genetic resources for food and agriculture in adaptation to and mitigation of climate change is presented in Appendix to this document.
    [Show full text]
  • Bees, Beekeepers, and Bureaucrats: Parasitism and the Politics of Transgenic Life
    EnvironmentandPlanningD:SocietyandSpaceadvance online publication doi:10.1068/d0510 Bees, beekeepers, and bureaucrats: parasitism and the politics of transgenic life Javier Lezaun Institute for Science, Innovation and Society, University of Oxford, Park End Street, Oxford OX1 1HP, England; e-mail: [email protected] Received 5 January 2010; in revised form 26 September 2010; published online 3 June 2011 Abstract. Over the last decade the flying patterns and foraging behavior of bees have become a matter of public policy in the European Union. Determined to establish a system where transgenic crops can `coexist' with conventional and organic farming, the EU has begun to erect a system of demarcations and separations designed to minimize the extent of `gene flow' from genetically modified plants. As the European landscape is regimented through the introduction of isolation distances and buffer zones, bees and other pollinating insects have become vectors of `genetic pollution', disrupting the project of cohabitation and purification devised by European authorities. Drawing on the work of Michel Serres on parasitism, this paper traces the emergence of bees as an object of regulatory scrutiny and as an interruptor of the `coexistence' project. Along with bees, however, another uninvited guest arrived unexpectedly on the scene: the beekeeper, who came to see his traditional relationship to bees, crops, and consumers at risk. The figure of the parasite connects the two essential dynamics described in this paper: an escalation of research and the intensification of political attributes. ``The founding of the naked, empty field, virgin once more, is the oldest work of the human world.'' Michel Serres (2007 The Parasite) At the turn of this century bees became a preoccupation of European bureaucrats.
    [Show full text]
  • The Cartagena Protocol and Biological Diversity; Biosafe Or Bio- Sorry
    Case Western Reserve University School of Law Scholarly Commons Faculty Publications 2000 The Cartagena Protocol and Biological Diversity; Biosafe or Bio- sorry Jonathan H. Adler Case Western University School of Law, [email protected] Follow this and additional works at: https://scholarlycommons.law.case.edu/faculty_publications Part of the Natural Resources Law Commons Repository Citation Adler, Jonathan H., "The Cartagena Protocol and Biological Diversity; Biosafe or Bio-sorry" (2000). Faculty Publications. 190. https://scholarlycommons.law.case.edu/faculty_publications/190 This Article is brought to you for free and open access by Case Western Reserve University School of Law Scholarly Commons. It has been accepted for inclusion in Faculty Publications by an authorized administrator of Case Western Reserve University School of Law Scholarly Commons. The Cartagena Protocol and Biological Diversity: Biosafe or Bio�Sorry? . JONATHAN H. ADLER* CONTENTS I. Introduction . 761 IT. TheThreat to Biodiversity. 764 ill. TheCartagena Protocol on Biosafety. 768 IV. Biosafety Versus Biodiversity. 772 V. Conclusion . 777 I. INTRODUCTION In February 1999, delegates from some 170 nations were summoned to Cartagena, Columbia to finalize an international protocol on the regulation of biotechnology. Under the auspices of the United Nations Convention on Biologi­ cal Diversity (CBD),1 national representatives and members of non-governmen­ tal organizations met to hammer out the details of a new regulatory regime for genetically modified organisms. "We need a widely accepted protocol that protects the environment, strengthens the capacity of developing countries to ensure biosafety, complements existing national regulations, and promotes public confidence in biotechnology and the benefits it can offer," proclaimed Klaus 2 Toepfer, executive director of the United Nations Environment Programme.
    [Show full text]
  • A Call to Protect Food Systems from Genetic Extinction Technology: the Global Food and Agriculture Movement Says NO to Release of Gene Drives
    A Call to Protect Food Systems from Genetic Extinction Technology: The Global Food and Agriculture Movement Says NO to Release of Gene Drives Gene drives are new tools that force genetically engineered traits through entire populations of insects, plants, animals and other organisms. This invasive technology represents a deliberate attempt to create a new form of genetic pollution. Gene Drives may drive species to extinction and undermine sustainable and equitable food and agriculture. Gene drives threaten natural systems. If released experimentally into the environment they may spread engineered genes uncontrollably through wild and domesticated species. This could alter ecological systems and food webs, harm biodiversity and eradicate beneficial organisms such as pollinators. Gene drives could disrupt lands, waters, food and fiber economies and harm Indigenous and peasant agroecological practices and cultures. Gene drives are being developed for use in agriculture. If applied, they may make farms even more genetically uniform and foreclose farmers’ rights, as enshrined, among others, in the International Treaty on Plant Genetic Resources for Food and Agriculture and in the UN Declaration on the Rights of Peasants and other People Working in Rural Areas. Use of gene drives may further entrench a system of genetically-engineered industrial agriculture, extend agro-toxin use and concentrate corporate control over global food systems, undermining the food sovereignty of farmers, food workers and consumers. Gene drives hinder the realization of human rights including rights to healthy, ecologically-produced and culturally appropriate food and nutrition. We, the undersigned, call for a global moratorium on any release of engineered gene drives. This moratorium is necessary to affirm the precautionary principle, which is enshrined in international law, and to protect life on Earth as well as our food supply.
    [Show full text]
  • Ecology: Biodiversity and Natural Resources Part 1
    CK-12 FOUNDATION Ecology: Biodiversity and Natural Resources Part 1 Akre CK-12 Foundation is a non-profit organization with a mission to reduce the cost of textbook materials for the K-12 market both in the U.S. and worldwide. Using an open-content, web-based collaborative model termed the “FlexBook,” CK-12 intends to pioneer the generation and distribution of high-quality educational content that will serve both as core text as well as provide an adaptive environment for learning. Copyright © 2010 CK-12 Foundation, www.ck12.org Except as otherwise noted, all CK-12 Content (including CK-12 Curriculum Material) is made available to Users in accordance with the Creative Commons Attribution/Non-Commercial/Share Alike 3.0 Un- ported (CC-by-NC-SA) License (http://creativecommons.org/licenses/by-nc-sa/3.0/), as amended and updated by Creative Commons from time to time (the “CC License”), which is incorporated herein by this reference. Specific details can be found at http://about.ck12.org/terms. Printed: October 11, 2010 Author Barbara Akre Contributor Jean Battinieri i www.ck12.org Contents 1 Ecology: Biodiversity and Natural Resources Part 1 1 1.1 Lesson 18.1: The Biodiversity Crisis ............................... 1 1.2 Lesson 18.2: Natural Resources .................................. 32 2 Ecology: Biodiversity and Natural Resources Part I 49 2.1 Chapter 18: Ecology and Human Actions ............................ 49 2.2 Lesson 18.1: The Biodiversity Crisis ............................... 49 2.3 Lesson 18.2: Natural Resources .................................. 53 www.ck12.org ii Chapter 1 Ecology: Biodiversity and Natural Resources Part 1 1.1 Lesson 18.1: The Biodiversity Crisis Lesson Objectives • Compare humans to other species in terms of resource needs and use, and ecosystem service benefits and effects.
    [Show full text]
  • The Effects of Introduced Tilapias on Native Biodiversity
    AQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS Aquatic Conserv: Mar. Freshw. Ecosyst. 15: 463–483 (2005) Published online in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/aqc.699 The effects of introduced tilapias on native biodiversity GABRIELLE C. CANONICOa,*, ANGELA ARTHINGTONb, JEFFREY K. MCCRARYc,d and MICHELE L. THIEMEe a Sustainable Development and Conservation Biology Program, University of Maryland, College Park, Maryland, USA b Centre for Riverine Landscapes, Faculty of Environmental Sciences, Griffith University, Australia c University of Central America, Managua, Nicaragua d Conservation Management Institute, College of Natural Resources, Virginia Tech, Blacksburg, Virginia, USA e Conservation Science Program, World Wildlife Fund, Washington, DC, USA ABSTRACT 1. The common name ‘tilapia’ refers to a group of tropical freshwater fish in the family Cichlidae (Oreochromis, Tilapia, and Sarotherodon spp.) that are indigenous to Africa and the southwestern Middle East. Since the 1930s, tilapias have been intentionally dispersed worldwide for the biological control of aquatic weeds and insects, as baitfish for certain capture fisheries, for aquaria, and as a food fish. They have most recently been promoted as an important source of protein that could provide food security for developing countries without the environmental problems associated with terrestrial agriculture. In addition, market demand for tilapia in developed countries such as the United States is growing rapidly. 2. Tilapias are well-suited to aquaculture because they are highly prolific and tolerant to a range of environmental conditions. They have come to be known as the ‘aquatic chicken’ because of their potential as an affordable, high-yield source of protein that can be easily raised in a range of environments } from subsistence or ‘backyard’ units to intensive fish hatcheries.
    [Show full text]
  • Genetically Engineered Trees the New Frontier of Biotechnology
    GENETICALLY ENGINEERED TREES THE NEW FRONTIER OF BIOTECHNOLOGY NOVEMBER 2013 CENTER FOR FOOD SAFETY | GE TREES: THE NEW FRONTIER OF BIOTECHNOLOGY Editor and Executive Summary: DEBBIE BARKER Writers: DEBBIE BARKER, SAM COHEN, GEORGE KIMBRELL, SHARON PERRONE, AND ABIGAIL SEILER Contributing Writer: GABRIELA STEIER Copy Editing: SHARON PERRONE Additonal Copy Editors: SAM COHEN, ABIGAIL SEILER AND SARAH STEVENS Researchers: DEBBIE BARKER, SAM COHEN, GEORGE KIMBRELL, AND SHARON PERRONE Additional Research: ABIGAIL SEILER Science Consultant: MARTHA CROUCH Graphic Design: DANIELA SKLAN | HUMMINGBIRD DESIGN STUDIO Report Advisor: ANDREW KIMBRELL ACKNOWLEDGEMENTS We are grateful to Ceres Trust for its generous support of this publication and other project initiatives. ABOUT US THE CENTER FOR FOOD SAFETY (CFS) is a national non-profit organization working to protect human health and the environment by challenging the use of harmful food production technologies and by promoting organic and other forms of sustainable agriculture. CFS uses groundbreaking legal and policy initiatives, market pressure, and grassroots campaigns to protect our food, our farms, and our environment. CFS is the leading organization fighting genetically engineered (GE) crops in the US, and our successful legal chal - lenges and campaigns have halted or curbed numerous GE crops. CFS’s US Supreme Court successes include playing an historic role in the landmark US Supreme Court Massachusetts v. EPA decision mandating that the EPA reg - ulate greenhouse gases. In addition, in
    [Show full text]
  • Impacts of Invasive Birds: Assessing The
    Impacts of invasive birds: assessing the incidence and extent of hybridization between invasive Mallard Ducks (Anas platyrhynchos) and native Yellow-billed Ducks (Anas undulata) in South Africa by Kirstin Stephens Thesis presented in partial fulfilment of the requirements for the degree of Master of Science in the Faculty of Science at Stellenbosch University Supervisor: Prof. Johannes J. Le Roux Co-supervisor: Dr. John Measey April 2019 Stellenbosch University https://scholar.sun.ac.za Declaration By submitting this thesis electronically, I declare that the entirety of the work contained therein is my own, original work, that I am the sole author thereof (save to the extent explicitly otherwise stated), that reproduction and publication thereof by Stellenbosch University will not infringe any third party rights and that I have not previously in its entirety or in part submitted it for obtaining any qualification. April 2019 Copyright © 2019 Stellenbosch University All rights reserved ii Stellenbosch University https://scholar.sun.ac.za Thesis Abstract Hybridization with invasive species is a major impact on native congeners, often leading to introgression and the loss of unique genotypes or co-adapted gene complexes. Therefore, hybridization needs to be managed through the removal of invasive species and their hybrids. Such management is often hampered, due to difficulties in identifying hybrids without genetic information, as hybrids are often morphologically indistinguishable from parental species. Consequently, genetic monitoring has become a useful tool in the detection and management of hybridization. Public opposition is often an additional barrier to the control of charismatic invasive species. In the case of the invasive Mallard Duck (Anas platyrhynchos) in South Africa, there is strong public opposition to their removal, founded in part, upon a lack of awareness of the potential threat that Mallard Ducks pose to the native Yellow-billed Duck (A.
    [Show full text]
  • Biological Invasions at the Gene Level VIEWPOINT Rémy J
    Diversity and Distributions, (Diversity Distrib.) (2004) 10, 159–165 Blackwell Publishing, Ltd. BIODIVERSITY Biological invasions at the gene level VIEWPOINT Rémy J. Petit UMR Biodiversité, Gènes et Ecosystèmes, 69 ABSTRACT Route d’Arcachon, 33612 Cestas Cedex, France Despite several recent contributions of population and evolutionary biology to the rapidly developing field of invasion biology, integration is far from perfect. I argue here that invasion and native status are sometimes best discussed at the level of the gene rather than at the level of the species. This, and the need to consider both natural (e.g. postglacial) and human-induced invasions, suggests that a more integrative view of invasion biology is required. Correspondence: Rémy J. Petit, UMR Key words Biodiversité, Gènes et Ecosystèmes, 69 Route d’Arcachon, 33612 Cestas Cedex, France. Alien, genetic assimilation, gene flow, homogenization, hybridization, introgression, E-mail: [email protected] invasibility, invasiveness, native, Quercus, Spartina. the particular genetic system of plants. Although great attention INTRODUCTION has been paid to the formation of new hybrid taxa, introgression Biological invasions are among the most important driving more often results in hybrid swarms or in ‘genetic pollution’, forces of evolution on our human-dominated planet. According which is best examined at the gene level. Under this perspective, to Myers & Knoll (2001), distinctive features of evolution now translocations of individuals and even movement of alleles include a homogenization of biotas, a proliferation of opportunistic within a species’ range (e.g. following selective sweeps) should species, a decline of biodisparity (the manifest morphological equally be recognized as an important (if often cryptic) and physiological variety of biotas), and increased rates of speci- component of biological invasions.
    [Show full text]
  • Section A. Crop Wild Relatives A.1
    SECTION A. CROP WILD RELATIVES A.1. Introduction What are crop wild relatives? Crop wild relatives (CWR) are taxa closely related to crops and are defined by their potential ability to contribute beneficial traits for crop improvement; for example, to confer resistance to pests and diseases, improve tolerance to environmental conditions such as extreme temperatures, drought and flooding, and to improve nutrition, flavour, colour, texture and handling qualities . A working definition of a CWR based on the Gene Pool concept or, in the 1 absence of crossing and genetic diversity information, the Taxon Group concept , has been proposed: ‘‘A crop wild relative is a wild plant taxon that has an indirect use derived from its relatively close genetic relationship to a crop; this relationship is defined in terms of the CWR belonging to gene pools 1 or 2, or taxon groups 1 to 4 of the crop’’. Pyrus salicifolia Pall., a wild relative of pear (P. pyraster Burgsd.), in Naxcıvan, Azerbaijan. This species grows in very dry and rocky areas; in some places the seeds of P. salicifolia are used to obtain the rootstock for local varieties of pears (photo: Mirza Musayev). Genetic erosion is a key problem for CWR. What is genetic erosion? Genetic erosion is a fundamental problem for CWR and has been referred to in the literature as the permanent reduction in richness (total number of alleles) or evenness (i.e. spread of allelic diversity)3 of common local alleles, or the loss of combinations of alleles over time in a defined area4. Genetic erosion can affect wild populations conserved in situ and ex situ collections (i.e.
    [Show full text]
  • How Does Human Activity Affect Species Extinctions?
    How Does Human Activity Affect Species Extinctions? od’s Word clearly artic - the resources He provided with the ulates His expectation “The ecological crisis original creation, others insist we that we should be faith - should join the largely secular move - ful stewards of His cre - is rooted in humankind’s ment to preserve that which remains ation (Genesis 2:15; Ex - of that creation. Godus 23:5, 10 -12; Leviticus 25:2-7, 23, greed and refusal to To gain a better perspective on 24; Numbers 22:23-33; Deuteronomy the relationship between human ac - 25:4; Matthew 12:11). Thus, we practice good and faithful tivities and species extinctions, we should become broadly informed on will first summarize the history of issues that affect life on our planet stewardship within the human-caused extinctions. We will and proactively accept our responsi - then describe three key lines of evi - bility to safeguard the wellbeing of divine boundaries of dence that humans have caused our cohabitants—the extraordinarily creation .” 1 many extinctions, a problem that diverse microbes, plants, and animals continues to gain alarming momen - that God created and repeatedly pro - Position Statement by the General Conference tum. Within this context, we will ex - nounced as “good” (Genesis 1). of Seventh-day Adventists plore the primary anthropogenic Today, many scientists believe we (human-related) causes of species are confronted with one of the planet’s greatest extinction extinctions and biodiversity loss. In the conclusion, we will re - events of all time, which has produced an ecological meltdown visit the Christian perspective on species extinctions and urge and biodiversity crisis.
    [Show full text]
  • "Loss of Biodiversity" Pdf File
    Home / Life / Biodiversity Loss of biodiversity Causes of the loss of biodiversity The main cause of the loss of biodiversity can be attributed to the influence of human beings on the world’s ecosystem, In fact human beings have deeply altered the environment, and have modified the territory, exploiting the species directly, for example by fishing and hunting, changing the biogeochemical cycles and transferring species from one area to another of the Planet. The threats to biodiversity can be summarized in the following main points: 1. Alteration and loss of the habitats : the transformation of the natural areas determines not only the loss of the vegetable species, but also a decrease in the animal species associated to them. Refer to “Alteration and loss of the habitats”. 2. Introduction of exotic species and genetically modified organisms ; species originating from a particular area, introduced into new natural environments can lead to different forms of imbalance in the ecological equilibrium. Refer to, “Introduction of exotic species and genetically modified organisms”. 3. Pollution : human activity influences the natural environment producing negative, direct or indirect, effects that alter the flow of energy, the chemical and physical constitution of the environment and abundance of the species; 4. Climate change : for example, heating of the Earth’s surface affects biodiversity because it endangers all the species that adapted to the cold due to the latitude (the Polar species) or the altitude (mountain species). 5. Overexploitation of resources : when the activities connected with capturing and harvesting (hunting, fishing, farming) a renewable natural resource in a particular area is excessively intense, the resource itself may become exhausted, as for example, is the case of sardines, herrings, cod, tuna and many other species that man captures without leaving enough time for the organisms to reproduce.
    [Show full text]