A recent hadrosaur discovery is forcing scientists to rethink some of their previously held notions about dinosaurs. Scientists believe that the duck-billed dinosaur grew to be as long as thirty feet and roamed ancient Alaska some 69 million years ago, during the late Cretaceous Period.
Researchers have concluded that the skeleton belongs to a new species of hadrosaur, one that is not related to previously discovered hadrosaurs in Canada and the rest of the United States. The skeleton is largely complete, and marks one of the most complete skeletons ever assembled. It appears that this dinosaur may have been adapted specifically to the cold weather found in Alaska.
Alaska turns out to be the key word here. Even 70 million years ago Alaska could be a cold, harsh place to live and prone to several months of darkness per year. During the late Cretaceous period much of Alaska was covered in relatively temperate polar forests that were heavily populated by deciduous trees, which lose their leaves during the winter. While summers in Alaska were relatively warm, the winters were long and cold (as they are now.)
As the atmosphere during the so-called age of the dinosaurs was filled with more greenhouse gases, the Earth was warmer overall. Much of the Earth was covered in lush forests and swampy jungles. Summers would have been longer and warmer, though as northern regions of the world would still suffer from several months of darkness due to the way the Earth rotates, winters would have still been very cold.
The hadrosaur, named Ugrunaaluk kuukpikensi, is one of only three dinosaurs so far discovered so far north. Since it lived in such harsh conditions, scientists are now questioning what they know about dinosaur physiology. Most importantly, scientists want to know how dinosaurs managed to survive so far up north. Researchers were able to piece together an essentially complete skeleton of the hadrosaur, which is so far the only complete skeleton assembled of a dinosaur found so far north. Scientists have found pieces of other skeletons.
The notion that dinosaurs were large, lethargic and cold-blooded animals has long since come to past. Still, the general presumption is that dinosaurs thrived only in warm climates. Besides surviving through cold temperatures, such dinosaurs would have also struggled to find food. One popular theory is that the dinosaurs could go into a sort of semi hibernation, or perhaps full hibernation, and endure a low-nutrient subsistence.
It’s possible that dinosaurs migrated during the winter months, but previous studies have suggested that the animals generally migrated only short distances or stayed in place. Given that the hadrosaur discovered in Alaska has not been observed elsewhere, it is possible that this dinosaur did, in fact, stay put. If so, it must have been uniquely evolved to survive the long, harsh winters found in the region.
Hadrosaurs are commonly referred to as “duck billed” dinosaurs. These dinosaurs thrived and were common during the Upper Cretaceous period, which was one of the final periods in the so-called “age of the dinosaurs.” This period is noted for its warm climate and rich vegetation. Hadrosaurs were herbivores. Owing to the difficulty of studying animals that have been extinct for millions of years, researchers know few concrete facts about the animals.
Interestingly, while it was originally thought that these dinosaurs spent much of their time in the water, it now appears that they actually lived mostly on land, but near water. While hadrosaurs may not be as flashy as a t-rex, these dinos have proven vital for helping us understand how these ancient animals lived and adapted to their environment.