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Biogeography is the study of the distribution of species and ecosystems in geographic space and through (geological) time. Organisms and biological communities often vary in a regular fashion along geographic gradients of latitude, elevation, isolation and habitat area.〔Brown University, "Biogeography." Accessed February 24, 2014. http://biomed.brown.edu/Courses/BIO48/29.Biogeography.HTML.〕 Phytogeography is the branch of biogeography that studies the distribution of plants. Zoogeography is the branch that studies distribution of animals. Knowledge of spatial variation in the numbers and types of organisms is as vital to us today as it was to our early human ancestors, as we adapt to heterogeneous but geographically predictable environments. Biogeography is an integrative field of inquiry that unites concepts and information from ecology, evolutionary biology, geology, and physical geography.〔Dansereau, Pierre. 1957. Biogeography; an ecological perspective. New York: Ronald Press Co.〕 Modern biogeographic research combines information and ideas from many fields, from the physiological and ecological constraints on organismal dispersal to geological and climatological phenomena operating at global spatial scales and evolutionary time frames. The short-term interactions within a habitat and species of organisms describe the ecological application of biogeography. Historical biogeography describes the long-term, evolutionary periods of time for broader classifications of organisms.〔Cox, C Barry, and Peter Moore. Biogeography : an ecological and evolutionary approach. Malden, MA: Blackwell Publications, 2005.〕 Early scientists, beginning with Carl Linnaeus, contributed theories to the contributions of the development of biogeography as a science. Beginning in the mid-18th century, Europeans explored the world and discovered the biodiversity of life. Linnaeus initiated the ways to classify organisms through his exploration of undiscovered territories. The scientific theory of biogeography grows out of the work of Alexander von Humboldt (1769–1859),〔von Humboldt 1805. ''Essai sur la geographie des plantes; accompagne d'un tableau physique des régions equinoxiales''. Levrault, Paris.〕 Hewett Cottrell Watson (1804–1881),〔Watson H.C. 1847–1859. ''Cybele Britannica: or British plants and their geographical relations''. Longman, London.〕 Alphonse de Candolle (1806–1893),〔de Candolle, Alphonse 1855. ''Géographie botanique raisonnée'' &c. Masson, Paris.〕 Alfred Russel Wallace (1823–1913),〔Wallace A.R. 1876. . ''The geographical distribution of animals''. Macmillan, London.〕 Philip Lutley Sclater (1829–1913) and other biologists and explorers. == Introduction == The patterns of species distribution across geographical areas can usually be explained through a combination of historical factors such as: speciation, extinction, continental drift, and glaciation. Through observing the geographic distribution of species, we can see associated variations in sea level, river routes, habitat, and river capture. Additionally, this science considers the geographic constraints of landmass areas and isolation, as well as the available ecosystem energy supplies. Over periods of ecological changes, biogeography includes the study of plant and animal species in: their past and/or present living ''refugium'' habitat; their interim living sites; and/or their survival locales.〔Martiny JBH et al. (Microbial biogeography: putting microorganisms on the map ) ''Nature: FEBRUARY 2006 | VOLUME 4''〕 As writer David Quammen put it, "...biogeography does more than ask ''Which species?'' and ''Where''. It also asks ''Why?'' and, what is sometimes more crucial, ''Why not?''."〔 〕 Modern biogeography often employs the use of Geographic Information Systems (GIS), to understand the factors affecting organism distribution, and to predict future trends in organism distribution.〔Cavalcanti, Mauro. (2009). Biogeography and GIS. http://digitaltaxonomy.infobio.net/?Software:Biogeography_and_GIS〕 Often mathematical models and GIS are employed to solve ecological problems that have a spatial aspect to them. Biogeography is most keenly observed on the world's islands. These habitats are often much more manageable areas of study because they are more condensed than larger ecosystems on the mainland.〔MacArthur R.H.; Wilson E.O. 1967. ''The theory of island biogeography''. ()〕 Islands are also ideal locations because they allow scientists to look at habitats that new invasive species have only recently colonized and can observe how they disperse throughout the island and change it. They can then apply their understanding to similar but more complex mainland habitats. Islands are very diverse in their biomes, ranging from the tropical to arctic climates. This diversity in habitat allows for a wide range of species study in different parts of the world. One scientist who recognized the importance of these geographic locations was Charles Darwin, who remarked in his journal "The Zoology of Archipelagoes will be well worth examination".〔 Two chapters in ''On the Origin of Species'' were devoted to geographical distribution. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「biogeography」の詳細全文を読む スポンサード リンク
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