When Continents Collide
When the Isthmus of Panama rose from the sea to connect South America to North America the two sets of animals came into competition. Who would win?
Amazing But True!
- North America and South America were separate. However, their animals, especially mammals, were very similar.
- About 2.5 million years ago, the volcanic Isthmus of Panama rose to connect the two continents through Central America. There was no competition between the two sets of animals.
- North American mammals prevailed in most cases.
- The Great American Interchange explains the migration of North American animals to South America and South American animals to North America. This migration occured in the Piancenzian age, approximately three million years ago.
Show What You Know
With the link below, learn more about the great American interchange. Then answer the following questions.
- Krulwich wonders, Look What You’ve Done, North America! (blog post): http://www.npr.org/blogs/krulwich/2013/07/24/205187973/look-what-you-ve-done-north-america
- When North and South America were separate what was going on with animals on both continents and why?
- What was the biggest difference between North American and South American mammals?
- Why did there need to be competition between the two sets of animals when the continents joined? Why does the author say that neither set had an obvious advantage?
- What is the hypothesis that scientists have for why the North American mammals did better than the South American mammals?
- Why are humans an exception to the rule of northern animals doing better than southern ones?