C.S. Lewis
The biogeography is a branch of the physical Géographie and ecology which studies the Vie on the surface of the sphere by analyzes descriptive and explanatory of the distribution of the living beings, and more particularly of the communities of living beings.
Indeed, the living beings are organized to give different landscapes which one calls “formations” (generally called according to their profiles or the vegetable formations the component). In fact the vegetable formations mark more Paysage, the alive plant (pertaining to the Biosphère), and which has interactions with the atmosphere, the Hydrosphère and the Lithosphère (the substrate).
A long time, the tendency of the biogéographes was to want to describe the space distribution of the living beings in a virgin Land of any anthropic influence. It was in particular the approach of Pierre Birot (1909-1984) in the vegetable formations of the sphere .
But this approach is called today into question. The concept of climax is contestable from the naturalist point of view, and the current forests are not comprehensible without taking account of the heritages of the glacial reconquest: certain sites of the Alps would have a hêtraie potentially but do not present any because the beech was not established there since its glacial refuges.
But it is not all. On forests which underwent centuries of practices usagères involving an impoverishment of the soil, the determinism climate-edaphology does not have any more a direction. The forest of Andaines, in Normandy, present of the very degraded grounds and the formations without relationship with the climaxes as defined by Henri Gaussen, as Gerard Houzard showed it. An extreme case is that of the Polémosystème: the forests developing on the old frontlines of 1914-1918 are absolutely aberrant from the naturalist point of view, and incomprehensible if account of the history is not taken.
This current approach, which develops in France since the beginning of the years 1980, constitutes the historical biogeography impelled by Gerard Houzard then Jean-Jacques Dubois.
Thus, two profiles are opposed or are complementary: the naturalists and the biogéographes. The latter utilize the human factors to describe the Paysage which mainly results from the action of the Man. The Écologie of the landscape tries to reconcile these two approaches.
Evolution of biogeography
The development of a discipine scientific master key generally by three or four phases. Biogeography illustrates this maturation well.The first phase is descriptive. As of the end of the 18th century, one of the first tests on the geography of alive was proposed by Buffon, but it is at the 19th century that was born really biogeography like scientific discipline. These fathers of biogeography are the explorers of 18th and 19th centuries, among which of Candolle, Alexander von Humboldt (1769-1859), Aimé Bonpland (1773-1858), Alfred Russel Wallace (1823-1913), Charles Darwin (1809-1882), Sir Julian Huxley (1887-1975), Philip Lutley Sclater (1829-1913)…
The following phase seeks to thus include/understand the history of faunas (that of the flora remaining then outstanding) their evolution. This research was started in a primarily narrative way however by Darwin, Wallace and Huxley but it is Ernst Mayr which adds really this temporal dimension in 1965: its objective being to analyze the origin, differentiation, the development and the installation of faunas in relation to the space-time history of the mediums.
The following stage with which the names with George Evelyn Hutchinson are associated (1903-1991), Robert MacArthur (1930-1972) and Edward Osborne Wilson (1929-) are the hypothético-deductive approach envisaging the distributions of the organizations and the processes implied starting from assumptions then to check on the ground the predictions of these assumptions. This predictive biogeography endeavors to explain fundamental mechanisms such as immigration, colonization, the extinction, the structuring and the renewal of the settlements. An example of this step is the theory of the insular biogeography of McArthur and Wilson (1963 and 1967).
The fourth phase is the experimental biogeography which consists in testing assumptions on some of the mechanisms studied by predictive biogeography: to create new mediums artificially, to split up spaces, to set up or remove in experiments barriers with colonization, to handle numbers of species on confined areas, to make substitutions of species, etc
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