In the Dinosaur Provincial Park in Alberta, Canada, researchers have uncovered a 76-million-year-old dinosaur tracksite. It may be the first ever evidence of a multitaxic dinosaur herd. That means that the herd contained not just more than one species, but more than one taxon of dinosaurs!
The Dinosaur Provincial Park is well-known for its fossil yields, but footprints are rare. Despite decades of collecting fossils there, researchers only discovered this site in 2024.
Ceratopsians with Ankylosaurs
The tracksite includes 13 clear ceratopsian (horned dinosaur) footprints, from at least five individuals walking side by side. An ankylosaur (armoured dinosaur) walked among them, indicating mixed-species movement.
Individual tracks of Ceratopsipes
Single track of possible ankylosaurid: (A) photograph. (B) digital model.
Nearby tracks of two large tyrannosaurs cross the herd’s path, hinting that this ceratops-ankylosaur grouping may have acted as protection against predators. Others also spotted a small theropod footprint.
Herding for Mutual Protection
The inclusion of an ankylosaur among ceratopsians hints at the idea of shared defense, since tyrannosaurid predators nearby possibly necessitated herd cooperation among herbivores. However, researchers caution that the tracks may have formed over several days, not in a single event, so conclusions on intent remain tentative.
“The tyrannosaur tracks give the sense that they were really eyeing up the herd, which is a pretty chilling thought. But we don’t know for certain whether they actually crossed paths”, said Dr. Bell
Individual tracks of tyrannosaurids.
So far, this is the first evidence that we have found of a mixed herd of different dinosaur species. Mixed herding is known in modern animals. For example, mixed herds of zebras and wildebeests are commonly seen in Africa.
Right Place at the Right Time
“Dinosaur Provincial Park in southern Alberta, Canada, is unquestionably one of the premier localities worldwide for understanding Late Cretaceous terrestrial ecosystems”, wrote the scientists in their paper. It has yielded hundreds of skeletons and huge numbers of isolated bones and teeth. That’s why it is considered an ideal location for understanding dinosaur evolution and palaeoecology.
Despite its abundance of fossils, dinosaur footprints and trackways are surprisingly rare here. This makes the discovery of these footprints all the more valuable.
“It was incredibly exciting to be walking in the footsteps of dinosaurs 76 million years after they laid them down,” adds co-lead author Brian Pickles. “Using the new search images for these footprints, we have been able to discover several more track sites within the varied terrain of the Park, which I am sure will tell us even more about how these fascinating creatures interacted with each other and behaved in their natural environment.”