Pachyrhinosaurus

Pachyrhinosaurus was one of the most unusual ceratopsians of the Late Cretaceous, distinguished by its remarkable lack of typical nose horns. Instead of the sharp horns seen in relatives like Triceratops, Pachyrhinosaurus bore thick, flattened bosses of bone on its nose and above its eyes — essentially rough, padded platforms that may have been used for shoving matches with rivals or intimidating predators.

This heavily-built herbivore roamed what is now Alberta, Canada, and Alaska approximately 73 to 69 million years ago. Like other ceratopsians, it likely lived in herds and spent its days cropping low-growing vegetation with its parrot-like beak. The elaborate frill at the back of its skull, adorned with various horns and projections depending on species, probably served for species recognition and display.

The first Pachyrhinosaurus fossils were discovered by legendary Canadian paleontologist Charles M. Sternberg in 1946 along the Red Deer River in Alberta. He formally named the genus in 1950, but the specimens remained relatively obscure for decades. It wasn't until the 1980s, when massive bonebeds containing dozens of individuals were excavated, that scientists could truly appreciate this dinosaur's anatomy and behavior.

The Alaskan specimens are particularly fascinating — they represent some of the northernmost dinosaurs ever found, suggesting Pachyrhinosaurus could tolerate cool, dark polar winters. Whether they migrated seasonally or endured months of darkness remains one of paleontology's intriguing mysteries.