In this month's issue of Smithsonian magazine, Eva Holland explores Canada's wealth of dinosaur fossils in the badlands of Alberta.
Drumheller, Canada, bills itself as the "Dinosaur Capital of the World" — hundreds of dinosaur skeletons have been found in the vicinity. The fossils come from 60 different species that date to the late Cretaceous period, representing as many as five percent of the world's known dinosaur species.
Alberta's Royal Tyrrell Museum is home to more than 150,000 fossils found near Drumheller, including species ranging from raptors to triceratops. But the museum isn't the only source of dinosaur information in the area — Francois Therrien, a paleontologist at the museum, believes a nearby canyon could hold new clues about the dinosaurs' extinction.
The K-T boundary, made up of the debris at a canyon carved by the Red Deer River, is the same debris left by an asteroid or comet that many believe killed the dinosaurs. The heat and collision from the impact would have killed many animals, but Therrien proposes that they may have already been a gradual decline among animal and plant species before the impact took place.
According to Therrien, climate change may have "weakened the dinosaurs enough to make an otherwise survivable event truly disastrous," Holland reports. Recent studies have concluded that some species of large herbivores may have declined before the dinosaurs' extinction, and the rocks along the Alberta river site may hold further clues about environmental change before the impact. Read more about the new theory and Alberta's dinosaur treasures over at Smithsonian.