Editing Biogeography (section)

===19th century===
Following the period of exploration came the [[Age of Enlightenment]] in Europe, which attempted to explain the patterns of biodiversity observed by Buffon and Linnaeus. At the birth of the 19th century, Alexander von Humboldt, known as the "founder of plant geography",<ref name=Cox /> developed the concept of physique generale to demonstrate the unity of science and how species fit together. As one of the first to contribute empirical data to the science of biogeography through his travel as an explorer, he observed differences in climate and vegetation. The Earth was divided into regions which he defined as tropical, temperate, and arctic and within these regions there were similar forms of vegetation.<ref name=Cox /> This ultimately enabled him to create the isotherm, which allowed scientists to see patterns of life within different climates.<ref name=Cox /> He contributed his observations to findings of botanical geography by previous scientists, and sketched this description of both the biotic and abiotic features of the Earth in his book, ''[[Cosmos (Humboldt)|Cosmos]]''.<ref name=Browne />

[[Augustin de Candolle]] contributed to the field of biogeography as he observed species competition and the several differences that influenced the discovery of the diversity of life. He was a Swiss botanist and created the first Laws of Botanical Nomenclature in his work, Prodromus.<ref name=Nicolson>{{cite journal | last1 = Nicolson | first1 = D.H. | year = 1991 | title = A History of Botanical Nomenclature | journal = Annals of the Missouri Botanical Garden | volume = 78 | issue = 1 | pages = 33–56 | doi = 10.2307/2399589 | jstor = 2399589 | url = https://www.biodiversitylibrary.org/part/35570 | access-date = 2022-06-25 | archive-date = 2021-08-12 | archive-url = https://web.archive.org/web/20210812103707/https://www.biodiversitylibrary.org/part/35570 | url-status = live }}</ref> He discussed plant distribution and his theories eventually had a great impact on [[Charles Darwin]], who was inspired to consider species adaptations and evolution after learning about botanical geography. De Candolle was the first to describe the differences between the small-scale and large-scale distribution patterns of organisms around the globe.<ref name=Browne />

Several additional scientists contributed new theories to further develop the concept of biogeography. [[Charles Lyell]] developed the Theory of [[Uniformitarianism]] after studying fossils. This theory explained how the world was not created by one sole catastrophic event, but instead from numerous creation events and locations.<ref name=Lyell>Lyell, Charles. 1830. Principles of geology, being an attempt to explain the former changes of the Earth's surface, by reference to causes now in operation. London: John Murray. Volume 1.</ref> Uniformitarianism also introduced the idea that the Earth was actually significantly older than was previously accepted. Using this knowledge, Lyell concluded that it was possible for species to go extinct.<ref>{{cite book|last1=Lomolino|first1=Mark V|first2=Lawrence R|last2=Heaney|year=2004|title=Frontiers of biogeography: new directions in the geography of nature|location=Sunderland, Mass|publisher=Sinauer Associates}}</ref> Since he noted that Earth's climate changes, he realized that species distribution must also change accordingly. Lyell argued that climate changes complemented vegetation changes, thus connecting the environmental surroundings to varying species. This largely influenced Charles Darwin in his development of the theory of evolution.<ref name=Browne />

[[Charles Darwin]] was a natural theologist who studied around the world, and most importantly in the [[Galapagos Islands]]. Darwin introduced the idea of natural selection, as he theorized against previously accepted ideas that species were static or unchanging. His contributions to biogeography and the theory of evolution were different from those of other explorers of his time, because he developed a mechanism to describe the ways that species changed. His influential ideas include the development of theories regarding the struggle for existence and natural selection. Darwin's theories started a biological segment to biogeography and empirical studies, which enabled future scientists to develop ideas about the geographical distribution of organisms around the globe.<ref name=Browne />

[[Alfred Russel Wallace]] studied the distribution of flora and fauna in the [[Amazon Basin]] and the [[Malay Archipelago]] in the mid-19th century. His research was essential to the further development of biogeography, and he was later nicknamed the "father of Biogeography". Wallace conducted fieldwork researching the habits, breeding and migration tendencies, and feeding behavior of thousands of species. He studied butterfly and bird distributions in comparison to the presence or absence of geographical barriers. His observations led him to conclude that the number of organisms present in a community was dependent on the amount of food resources in the particular habitat.<ref name=Browne /> Wallace believed species were dynamic by responding to biotic and abiotic factors. He and Philip Sclater saw biogeography as a source of support for the theory of [[evolution]] as they used Darwin's conclusion to explain how biogeography was similar to a record of species inheritance.<ref name =Browne /> Key findings, such as the sharp difference in fauna either side of the [[Wallace Line]], and the sharp difference that existed between North and [[South America]] prior to their relatively recent [[Great American Interchange|faunal interchange]], can only be understood in this light. Otherwise, the field of biogeography would be seen as a purely descriptive one.<ref name =Cox />