Polar Dinosaurs Endured Cold Dark Winters

Polar dinosaurs such as the 3.3-ton duckbill Edmontosaurus are thought by some paleontologists to have been champion migrators to avoid the cold, dark season. But a study now claims that most of these beasts preferred to stick closer to home despite potentially deadly winter weather.

While some polar dinosaurs may have migrated, their treks were much shorter than previously thought, University of Alberta researchers Phil Bell and Eric Snively conclude from a recent review of past research on the animals and their habitat. Polar dinosaurs include hadrosaurs, ceratopsians, tyrannosaurs, troodontids, hypsilophodontids, ankylosaurs, prosauropods, sauropods, ornithomimids and oviraptorosaurs.

This idea goes against a once-popular "Happy Wanderers" theory published in 1980 by paleontologist Nicholas Hotton III, who thought that long-distance migration allowed polar dinosaurs to escape the coldest winter temperatures. ...

In fact, some evidence suggests polar dinosaurs tolerated the cold remarkably well and adapted to lasting through the tough winters, Bell and Snively write. Sauropods, theropods and ankylosaurs all endured three months of winter darkness, possibly foraging on tough stuff like conifers, ginkgoes, horsetails and ferns, rather than hibernating or burrowing, some research suggests.

The mean annual temperatures at the poles were warmer than they are today, around 41 degrees Fahrenheit (5 degrees Celsius), according to research noted by Bell and Snively. This meant more foliage was available for munching, and also blocked movement and left less wide open space for migration.

Also, it is now known that some small theropod dinosaurs, including some tyrannosaurs, had feathers that could have kept them warmer in colder climates. Among polar dinosaurs, that could apply to troodontids, ornithomimids and oviraptorosaurs, which are all theropods. - livesci

Do the Ica Stones show any dinosaurs with feathers? They do show plenty of patterns. T-Rex with feathers? They seem to show a bumpy feature of dinosaur skin recently discovered: