When Dinosaurs Ruled the Arctic Circle

Pachyrhinosaurus and Edmontosaurus - undertook an epic migration every year to reach the fertile grounds of the northern latitudes in summertime. This was far from an easy task. Deadly predators lurked nearby looking to pick off weaker members of this giant herd. But evidence is starting to suggest that these two maybe have used their complementary strengths to fend off predators and communicate.