Educator Resources main content.

Educator Resources

While excavating just outside Yellowstone National Park, a team led by paleontologist Jonathan Bloch of the Florida Museum of Natural History discovered two remarkably preserved fossils. The 56-million-year-old specimens belong to a group of archaic mammals, the plesiadapiforms (please-ee-ah-DAPE-i-forms). These small mammals were as small as mice, ate fruit, and lived in trees. The new fossils offered compelling evidence that the plesiadapiforms are more closely related to modern primates than to flying colugos, which had previously been proposed. Instead of having webbed hands or gliding flaps like colugos, plesiadapiform fossils showed hands that could grasp and manipulate food—a defining trait of primates.

Class Discussion

Have students view the snapshot. For more background information, have students read the article on this related link:

Then use the following questions to guide a class discussion:

  • What new discovery did paleontologist Jonathan Bloch and his team make?
  • How about “what did they look like?” instead?
  • Plesiadapiforms were once thought to be related to colugos. What did the new fossils show?
  • What defining trait of primates did plesiadapiforms have?
  • What is the significance of identifying plesiadapiforms as primates?

Copyright © 2004-2007 American Museum of Natural History. All rights reserved.