Paleontologists have suggested this was the case, as so many Tyrannosaurus fossils are found clustered together. But scientists could never be sure whether a group lived and perished in close proximity or were swept away by flood waters and deposited in the same location.
But a set of Tyrannosaurus tracks -- found, as so many other dinosaur fossils are, in British Columbia -- suggests the fearsome predators migrated in groups and scoured the tundra of western North America in search prey in an organized fashion.
Paleontologists at the Peace Region Paleontology Research Center in Tumbler Ridge, British Columbia, confirmed the three sets of pristinely preserved Tyrannosaur tracks were made at the same time. They show all three dinos were of similar age and traveling in the same direction. They belong to one of the three Tyrannosaurus species that populated B.C. and Alberta some 70 million years ago -- Albertosaurus, Gorgosaurus and Daspletosaurus -- all cousins to the better known T. rex.
"When you find three trackways together, going in same direction, it's not necessarily good evidence for gregarious behaviour. They could be walking along a shore. But if all the other animals are moving in different directions, it means there is no geographical constraint, and it strengthens the case," explained Richard McCrea, curator of paleontology at the research center and lead author of a new study on the findings -- published this week in the journal PLOS ONE.
"It's about as strong evidence as you can get without going back in a time machine and observing them," McCrea added.