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The Great American Biotic Interchange
1Department of Anatomy, Case Western Reserve University School of Medicine, Cleveland, OH, USA.
Current Biology : CB
|July 20, 2026
Summary
The Isthmus of Panama's emergence 5 million years ago enabled a two-way exchange of large land mammals. This event significantly impacted animal migration and biodiversity across the Americas.
Area of Science:
- Paleontology
- Zoology
- Geology
Background:
- The formation of the Isthmus of Panama approximately five million years ago was a pivotal geological event.
- This land bridge connected North and South America, facilitating faunal interchange.
Purpose of the Study:
- To introduce the concept of the Great American Biotic Interchange.
- To highlight the two-way exchange of large land animals following the isthmus's emergence.
Main Methods:
- Review of paleontological and geological evidence.
- Analysis of fossil records detailing faunal distribution.
Main Results:
- Documented the significant migration of large land mammals between the two continents.
- Identified distinct North American and South American fauna that crossed the isthmus.
Conclusions:
- The emergence of the Isthmus of Panama triggered a major event in evolutionary history.
- This interchange profoundly shaped the mammalian ecosystems of North and South America.
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