景观遗传学简介
随着人类活动能力的增强,人类对景观的改变和塑造能力也达到了历史中的最高点。物种的生存空间和生存质量受到了极大的威胁。正如Hanski在他的《萎缩的世界》里所描述的,这个世界正在急剧萎缩。
萎缩的世界里,不同的物种将做什么反应呢?这是我们,包括生态学家、保护生物学家、进化生物学家、景观管理者等所关心的问题,并且给予了极大的研究热情。
景观遗传学正是在这种科学和现实的背景下应运而生的。景观遗传学从遗传进化的角度研究景观破碎化对物种和种群的影响。景观遗传学源于种群遗传学和景观生态学 在理论和方法上的交叉,但其对空间异质性的分析使这个学科有别于种群遗传学和景观生态学。通过解译存在于种群内和种群间的空间遗传格局(Spatial Genetic Structure,SGS),去推测景观格局和环境因子对物种进化的影响。景观遗传学的研究结果将为景观管理和生物保护提供有意义的参考(Manel et al. 2003, Holderegger & Wagner 2006)。
空间模型发展的三个阶段:
第一阶段是岛屿模型。很多经典的种群遗传学理论都是从这个模型推倒得出的,比如可以通过种群间遗传分化程度估计平衡种群间的基因流。这个模型基本上不考虑空间信息,种群的基因流默认为是一个相同的固定值;
第二阶段是复合种群模型。因为对空间信息处理的一统化和模糊化,岛屿模型很难解释其观测到的遗传分布格局。复合种群模型将空间分布的种群看成是不均一的,存在灭绝和再定殖。这个模型的发展也促使人们在景观尺度上思考遗传分布的格局和起因。
邬建国老师的《景观生态学》书上(P45,第一版)有关于复合种群的类型和特征的描述。复合种群模型强调种群空间的不均一性,更多的是从种群本身的性质出发去反映遗传分布和空间的关系,比如种群大小、性比,Manicacci等人1992年有过这方面的论述(在“LG文献第一帖”上已附上此篇文章)。这些因素具有很强的空间相关性,但是并不能直接反映遗传的空间分布规律。Hanski & Gaggiotti (2004,Ecology, Genetics and Evolotion of Metapopulation),其中关于“Metapopulation Genetics”章节的讨论,是一种空间隐式模型,空间信息被简化在种群分化系数FST中。
第三阶段是景观模型。“复杂性和不完美性”无法阻止景观模型最近二十多年的快速发展和运用,因为相比简化模型而言,其更接近现实,对特定问题具有更强的预测性。景观模型的思想运用到遗传格局的空间分析上,也就催生了“景观遗传学”。
景观遗传学研究什么?下面是景观遗传学重要的文献中给出的一些定义:
Manel et al. TREE(2003) Landscape genetics: combining landscape ecology and population genetics
“...landscape genetics, which is an amalgamation of molecular population genetics and LANDSCAPE ECOLOGY. This discipline aims to provide information about the interaction between landscape features and microevolutionary processes, such as gene flow, genetic drift and selection.”
Holderegger & Wagner Landscape Ecology (2006) A brief guide to Landscape Genetics
"landscape genetics endorses those studies that combine population genetic data, adaptive or neutral, with data on landscape composition and configuration, including matrix quality. "
Storfer et al. Heredity (2007) Putting the ‘landscape’ in landscape genetics
"Landscape genetics has emerged as a new research area that integrates population genetics, landscape ecology and spatial statistics. ...landscape genetics provides a framework for testing the relative influence of landscape and environmental features on gene flow, genetic discontinuities (Guillot et al., 2005a) and genetic population structure."
景观遗传学的定义在某些程度上泛化。学科发展之初,很难用一个严格的框架定义它,另一方面,也许确实是为了吸引更多的不同生物学背景的人参与到这一交叉研究中来。不过,对于景观遗传学,我们仍有这样一些共识:遗传的空间分布规律是其重要研究内容,通过探讨这种分布规律和景观的关系,来思考景观的功能。
景观遗传学研究近期迅速升温,更多的是出于物种保护目的的需要。我们急需要了解物种生存能力的空间依赖关系以及如何实施我们的保护计划,如何管理我们的景观。景观遗传学也许提供了一个很好的思路和方法。
 
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国际上作景观遗传学的实验室或机构
University of Idaho Lab for Ecological & Conservation Genetics
http://www.cnrhome.uidaho.edu/default.aspx?pid=78477 景观遗传理论和方法研究小组。
Brad McRae National Center for Ecological Analysis and Synthesis University of California, Santa Barbara http://www.nceas.ucsb.edu/~mcrae/
Andrew Storfer Washington State University, School of Biological Sciences Amphibian Range Limits: Comparative Studies of Geographic istributions of Genetic Variation http://www.wsu.edu/~storfer/index.html
Wildlife Genetics Purdue University http://www.agriculture.purdue.edu/fnr/html/faculty/Rhodes/walnut.html http://www.agriculture.purdue.edu/fnr/html/faculty/Rhodes/genetics.html
Population genetics and Geographic Information Systems GEO 565: Annotated Bibliography By Josef Uyeda http://dusk2.geo.orst.edu/gis/student_bibs/uyeda.html
Landscape genetics of southwestern coyotes http://www.vgl.ucdavis.edu/research/canid_diversity/projects/coyotes.html
Landscape Genetics of the Great and Little Miami Watersheds http://www.epa.gov/eerd/LandGen.htm
Application of landscape genetics to predicting the spread of chronic wasting disease in Wisconsin http://wildlife.wisc.edu/coop/CWD/LandGen_Page.html
Natural Resources DNA Profiling and Forensic Centre DNA Building, Trent University, Canada http://web.nrdpfc.ca/landscapegenetics.html
Landscape genetics of invading and recipient ladybird species NERC Reference : NE/F012101/1(一个小的资助项目) http://sotw.nerc.ac.uk/list_full.asp?pcode=NE%2FF012101%2F1
Cornelia Bae?ler Germany Department of Community Ecology Helmholtz-Centre for Environmental Research - UFZ http://www.ufz.de/index.php?de=7264
Dr. Nusha Keyghobadi Molecular ecology and landscape genetics The University of Western Ontario http://www.uwo.ca/biology/Faculty/keyghobadi/index.htm
Yixin Zhang, Ph.D. Assistant Professor Department of Biology Freeman Aquatic Building Texas State University - San Marcos http://www.bio.txstate.edu/~zhang/ This project is studying the Hong Kong newt (Paramesotriton hongkongensis).
Landscape Genetics of Swamp Rabbits and Bobwhite Quail in Illinois http://www.siu.edu/~wildlife/c_nielsen/berkman.html Cooperative Wildlife Research Laboratory, Southern Illinois University Carbondale
Comparative Landscape Genetics of Darwin's Finches http://www.biology.uc.edu/faculty/petren/LAB/research.html
Landscape genetic patterning of Walleye Sander vitreus: Vicariance, postglacial dispersal and spawning philopatry Carol A. Stepien, Rachel N. Lohner, and Douglas J. Murphy Population and Fishery Genetics of Walleye http://www.utoledo.edu/as/lec/fishery/walleye/Walleye.html
Population Genetics Seminar http://dbs.umt.edu/courses/biol561/schedule.htm The University of Montana, Missoula
Evolutionary Biology at San Diego State University
http://www.bio.sdsu.edu/eb/pubs.html (发表文章)
David O. Wallin Ongoing Research Interests http://www.ac.wwu.edu/~wallin/research.htm
Royal Botanical Gardens http://myprofile.cos.com/proteus
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