Pachyrhinosaurus lakustai lived during the end of the Cretacious Period, approximately 89-65 million years ago when the earth was significantly warmer and much more humid.
It was about 6 meters (20 feet) long.
The remains from the Pipestone Creek site (Alberta, Canada) indicate that the herd was comprised of four distinct sizes - from juvenile to maturity; proving that these dinosaurs cared for their young.
Pachyrhinosaurus traveled in herds and migrated seasonally, following plant food resources.