News Paleontology

A flexible bone that helps mammals chew dates back to the Jurassic Period

The structure may have helped give rise to the Age of Mammals, a new fossil suggests

Microdocodon gracilis fossil

JURASSIC CHEWER  This fossil of the shrew-sized mammal ancestor Microdocodon gracilis, which lived about 165 million years ago, reveals that the shape of the hyoid, a flexible bone that aids in chewing, is similar to that of modern mammals. 

Z.-X. Luo/Univ. of Chicago

By Carolyn Gramling

- More than 2 years ago

Chew on this: Millions of years before the emergence of true mammals, an early ancestor had a tiny, saddle-shaped bone connected to the jaw that was thought to belong to mammals alone.