Biology 2483A Lecture Notes - Lecture 17: Estuary, Allopatric Speciation, Krakatoa

• School: Western University
• Department: Biology
• Course: Biology 2483A
• Professor: Hugh Henry

Document Summary

Biogeography is the study of patterns of species composition and diversity across geographic locations. In general, the lower latitudes have many more, and different, species than higher latitudes. For example, the amazon rainforest is the most species-rich forest in the world, with approximately 1,300 tree species. In contrast, the boreal forests of canada have only two tree species that cover vast areas. Species richness and composition also vary from continent to continent. The same community type or biome can vary in species richness and composition depending on its location on earth. Ecologists have worked to understand the processes that control these broad patterns. A number of hypotheses have been proposed, which are highly dependent on spatial scale. Here species have been isolated from one another, on different continents or in different oceans, by long distances and over long periods rates of speciation, extinction, and dispersal help determine differences in species diversity and composition.