Project: K12 - Great American Biotic Interchange

About the project

The Great American Biotic Interchange (GABI) was catalyzed by the formation of the Isthmus of Panama during the Neogene. The GABI had a profound effect on the evolution and geography of terrestrial organisms throughout the Americas and marine organisms globally. For example, more than 100 genera of terrestrial mammals dispersed between the Americas, and numerous marine organisms had their interoceanic distributions cut in half by the formation of the Isthmus. The GABI is widely considered to have been a grand natural experiment documented by the fossil record. In addition to biotic effects, the formation of the Isthmus also affected oceanic circulation, global climates, and possibly triggered the Ice Ages during the Pleistocene. Over the past several years, new discoveries have dramatically impacted our scientific understanding of GABI. Until recently, the paradigm depicts final closure of the Isthmus during the Pliocene about 4 million years ago, and the dispersal of land mammals north and south commencing thereafter. However, this traditional scenario is being challenged by new fossil discoveries. Thus, rather than being considered a single event that occurred about 4 million years ago, the GABI likely represents a series of dispersals over the past 10 million years, some of which occurred before full closure of the Isthmus. New fossil discoveries in Panama resulting from the GABI RET (Research Experiences for Teachers) are thus contributing to the understanding of the complexity and timing of the GABI during the Neogene. This group of fossils are meant to facilitate K12 educators with examples of animals that are part of the GABI. We will be adding fossils as we scan them.

Metadata and usage reports

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Jonathan Bloch, Sean Moran, Claudia Vargas-Vergara, Michael Ziegler


10 published media groups owned by this project
10 published media groups associated with project specimens
6 project specimens
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uf:uf:19420, Gomphotherium gomphotherium

Created 2/9/2017 at 15:25
Modified 6/2/2017 at 14:53
uf:uf:206880, Eremotherium eomigrans

Created 2/18/2017 at 21:03
Modified 10/17/2017 at 20:55
uf:uf:30003, Titanis walleri

Created 12/7/2016 at 10:20
Modified 6/2/2017 at 14:53
uf:uf:4109, Titanis walleri

Created 3/1/2017 at 13:01
Modified 6/2/2017 at 14:53
uf:uf:52375, Megalonyx leptostomus

Created 12/7/2016 at 9:29
Modified 10/17/2017 at 20:55
uf:uf/tro:564, Phugatherium dichroplax

Created 2/6/2017 at 18:00
Modified 6/2/2017 at 10:16