One T-Rex would be scary enough. A new discovery in Canada suggests one of the most fearsome dinosaurs hunted in packs. They may have “stuck together as a pack to increase their chances of bringing down prey and individually surviving,” said study co-author Richard McCrea.
McCrea is a curator at the Peace Region Paleontology Center in Canada. The study was published in PLOS ONE yesterday.
The theory that the tyrannosaur was a pack hunter isn’t a new one, but it is a controversial one. Most researchers believe the T-Rex along with its cousin, the Albertosaurus, were lone wolves.
A discovery of multiple Albertosaurus fossils in a single bone bed in Canada’s Dry Island Buffalo Jump Provincial Park has led some to question this lone wolf theory. The finding of fossils together doesn’t mean the tyrannosaur roamed in packs, though. There’s plenty of explanations for how the fossils accumulated in one spot.
McCrea acknowledges this as he points to how the La Brea tar pits in Los Angeles was the site of many carnivores deaths as they wandered into it.
The track discovery supports the pack hunter theory though. McCrea’s team found a patch filled with footprints from multiple dinosaurs. Tyrannosaurs and other smaller dinosaurs walked the nearly 200 foot long patch that was discovered. The dinosaurs walked through a silty sediment from an overflowing river about 70 million years ago.
The other dinosaur tracks pointed in random directions, but not the T-Rex tracks. The team found seven tracks made by three tyrannosaurus’ that were parallel to each other. The three tyrannosaurs’ tracks were roughly the same depth in the sediment. This points to the three moving around it at roughly the same time. The depth of the print would change as sediment dried.
“The hadrosaur footprints are much more shallow, indicating that they came later,” McCrea told Live Science.
McCrea also pointed out how pack hunting would explain how tyrannosaurs could kill a hadrosaurs, a dinosaur about as big as a tyrannosaur, without be significantly hurt.
While they may have helped one another on the hunt, other fossils show the dinosaurs liked to head-bite each other. Not something buddies typically do.