A University of Calgary paleontologist shows off a Pachyrhinosaurus skull . It 's one of the biggest , if not the biggest , of its kind at 2 to 2.5 meters , she says . It took several more months ( and the removal of 5 tons of rock ) to unearth it in three pieces and show it off to the world . The discovery is significant because it suggests that giant dinosaurs were more diverse than previously thought and may have been able to adapt their lifestyles in response to changing environmental conditions as they spread across North America during Pachyrhinosaurs lived about 70 million years ago in Calgary 's Alberta and Alaska .
A University of Calgary paleontologist shows off a Pachyrhinosaurus skull . It 's one of the biggest , if not the biggest , of its kind at 2 to 2.5 meters , she says . The discovery is significant because it suggests that giant dinosaurs were more diverse than previously thought and may have been able to adapt their lifestyles in response to changing environmental conditions as they spread across North America during Pachyrhinosaurs lived about 70 million years ago in Calgary 's Alberta and Alaska .