Were dinosaurs warm-blooded? Scientists just discovered a new species of the duck-billed hadrosaur that roamed the plains of Alaska. The newly found herbivore is named Ugrunaaluk kuukpikensis, or “ancient grazer” in Inupiaq, the language of the native Alaskan Inupiat people. This ancient creature is the fourth dinosaur species to be identified in Northern Alaska, and its discovery further opens a window into what Gregory Erickson of Florida State calls “a lost world of dinosaurs that we didn’t realize existed.”
Although the global climate of the Mesozoic Era, during which the dinosaurs reigned, was considerably warmer and wetter than it is today, the planet still maintained a diversity of biomes. Ecosystems flourished even near the Arctic Circle, where the Earth’s tilt then and now causes months of winter darkness. Even in the dark, “life finds a way.”
Although the ancient Alaskan climate was cool, it was far from the tundra we know today. “It was certainly not like the Arctic today up there—probably in the 40s was the mean annual temperature,” says Erickson. “Probably a good analogy is thinking about British Columbia.” Mark Norell, curator of paleontology at the American Museum of Natural History in New York, suggested Ugrunaaluk likely lived in the Arctic year-round, since long-range seasonal migrations would have been too strenuous on juvenile dinosaurs.
Ugrunaaluk kuukpikensis grew to be 30 feet long and had hundreds of teeth, which it used to grind and tear the tough vegetation it ate. Although the dinosaur could use all four legs in its locomotion, it usually would have been standing on two legs. While it’s clear Ugrunaaluk was not the only dinosaur in the neighborhood, scientists have not yet found any fossils from crocodiles, turtles, lizards or other cold-blooded reptiles. This suggests that perhaps dinosaurs were warm-blooded, able to regulate their own body temperature to make them more resilient against the cold. The discovery is documented in a recently published paper by researchers at Florida State and Alaska University. If you can’t get enough of polar dinosaurs, be sure to check out Walking With Dinosaur’s Spirits of the Ice Forest.