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Into The Tropics: A Quantitative Study Of Mammals In The Great American Biotic Interchange, Winifred Whiteman-Jennings

Biology ETDs

For almost 100 million years, North and South America were isolated from each other. This long period of geologic separation led to the evolution of strikingly different mammalian faunas: marsupials were prevalent in South America, while ecosystems in North America were composed of placental mammals. Roughly 3 Mya, a land bridge formed between the two continents leading to an accelerated exchange of mammalian fauna. The Great American Biotic Interchange (or GABI, as this has come to be called,) led to the successful colonization of many North American species, but few South American species. The highly asymmetrical nature of the faunal …