230 Million-Year-Old Fossil From Wyoming Challenges Dinosaur Origin Theories

A chicken-sized dino, the oldest known in North America, has thrown a wrench in the widely accepted timeline of early dinosaur history.

230 Million-Year-Old Fossil From Wyoming Challenges Dinosaur Origin Theories
A chicken-sized dino, the oldest known in North America, has thrown a wrench in the widely accepted timeline of early dinosaur history.