Dinosaur species had made the Arctic their permanent home and probably developed techniques to survive the cold, according to a new study published in Current Biology.
This study is the first to provide evidence that at least seven species of dinosaurs were able to reproduce at these extremely high latitudes. Species discovered include hadrosaurids (or duck-billed dinosaurs), horned dinosaurs like ceratopsians, and carnivores like tyrannosaurs. “We associate dinosaurs with tropical environments, but the whole Earth was not like that “, says Patrick Druckenmiller, lead author of the study (University of Alaska Museum of the North). The Arctic was warmer then than it is today, but conditions were still very demanding. The annual temperature was around 6 ° C, but much lower temperatures were the order of the day, with snowfall, in the winter.
“We now know that most of the carnivorous dinosaurs there probably had feathers.. You can imagine this as their own down jacket, to help them survive the winter. “ Researchers believe the smaller herbivores would bury themselves underground and hibernate. And the older ones, with more fat reserves, relied on lower quality twigs and bark to get through the winter. On the other hand, the fact that dinosaurs stayed in the Arctic all year round is further clue to the idea that dinosaurs were warm-blooded animals. They would then represent a point of evolution between cold-blooded reptiles and warm-blooded birds.