The 1950s discovery of dinosaur bones in the Arctic sparked controversy over whether there was a permanent dinosaur presence at higher latitudes, or whether large animals migrated there for the summer. Subsequent evidence supported the idea that some dinosaur species survived long nights in both the Arctic and Antarctic, but a new study in current biology revealed further: Many species lived there. Paleontologists have previously found evidence of habitat near the Arctic Circle. However, the species involved could not be identified. Dr. Patrick Druckenmiller of the University of Alaska readily accepted such an invention.
“We have not only shown the presence of presence remains in the eggs of one or two species or simply scattered, but we have documented at least seven species of dinosaurs breeding the arc,” he said in a statement. “This is the first time anyone has shown that dinosaurs can reproduce at these high latitudes,” says Druckenmiller. The Prince Creek Formation site sits on the Colville River in Alaska and is located 5-10 degrees from the pole towards the end of the Cretaceous.
The Earth was then a warmer place, but the average temperature at the site throughout the year is still thought to be around 6 degrees Celsius (42ºF). There was almost no sun and precious little warmth for four months every winter. Yet, this position supports a great deal of life. Drakenmiller and colleagues found hundreds of bones and teeth of baby dinosaurs. Some did not lay eggs, while others suffered the unfortunate consequences of hatching.
Instead of reflecting on a variety of closely related species, their findings include hydrocephalus, ceratopsians (a family that includes thescelosaurs), thescelosaurs, and even tyrannosaurus and other carnivores. Although families are known, most of the individual species are new to science. “It didn’t happen so long ago that the idea of finding any dinosaurs in this kind of final latitude and environment was surprising,” Druckenmiller said. “Then find out that not all of the species that reproduced the arc are really significant. We’ve been asked for a long time, ‘Did you find any eggs?’ [We] still answer ‘no’. However, we have much better: the real baby dinosaurs themselves.”