FOOTPRINTS found in Canada are the first evidence of social interaction between different dinosaur species more than 75 million years ago, scientists have said.
The findings of a new study by an international team of researchers, published today, indicate that multiple species of dinosaur were herding together, similar to how species such as zebra and wildebeest co-herd.
Teams were led by the University of Reading’s Dr Brian Pickles; Dr Phil Bell of the University of New England, Australia; and Dr Caleb Brown of Royal Tyrrell Museum of Palaeontology in Canada.
Researchers were working at Dinosaur Provincial Park in Alberta, Canada–world-famous for its abundant fossils, but dinosaur footprints were virtually unknown at the site.
The discovery, made during an international field course in July 2024, includes footprints from multiple dinosaur species walking alongside each other, which researchers say is the first evidence of mixed-species herding behaviour in dinosaurs.
The teams were also surprised to find the tracks of two large tyrannosaurs walking side-by-side, perpendicular to the herd.
They say this raises the prospect that the multispecies herding may have been a defence strategy against common apex predators, but more evidence is needed to confirm this.
Excavation of 29 square metres of the site revealed 13 horned dinosaur (ceratopsian) tracks from at least five animals walking side by side, with a probable armoured dinosaur (ankylosaurid) walking in the midst of the others.
The full findings of the study were published in the Open Access Journal PLOS One today, Wednesday, July 23.
Dr Phil Bell, University of New England, said: “I’ve collected dinosaur bones in Dinosaur Provincial Park for nearly 20 years, but I’d never given footprints much thought.
“This rim of rock had the look of mud that had been squelched out between your toes, and I was immediately intrigued.
“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.”
Dr Brian Pickles, University of Reading, said: “It was incredibly exciting to be walking in the footsteps of dinosaurs 76 million years after they laid them down.
“Using the new search images for these footprints, we have been able to discover several more tracksites 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.”
Dr Caleb Brown, Royal Tyrrell Museum of Palaeontology, added: “This discovery shows just how much there is still to uncover in dinosaur palaeontology.
“Dinosaur Park is one of the best understood dinosaur assemblages globally, with more than a century of intense collection and study, but it is only now that we are getting a sense for its full potential for dinosaur trackways.”
The study is available to read on the DOI Foundation via: doi.org/10.1371/journal.pone.0324913
