Dinosaur fossils come in all shapes and sizes, but complete skeletons are among the rarest of finds. Well preserved remains of young prehistoric beasts, meanwhile, are even more difficult to come by. So, when a team of researchers unearthed an intact baby skeleton, they were understandably astonished at their discovery. But what the remains told them about both how the creature lived and how it died would be even more amazing.
Back in 2010 archaeologists were digging in Dinosaur Provincial Park near Calgary, Canada, when they came across something astonishing. Indeed, their find was unlike anything they’d seen before.
The park is a hive of fossil-related activity, having gained UNESCO World Heritage status in 1979. Over the past few decades, then, researchers have unearthed dozens of dinosaur species from the land there. And most of them are on display at the nearby Royal Tyrrell Museum, which opened in 1985.
Now, Dr. Philip Currie was one of the researchers on the 2010 dig. Known as one of the men who inspired Jurassic Park’s Alan Grant, Currie works as a research associate for the Tyrrell Museum and is also a paleobiologist at the University of Alberta.
While digging away in a hillside, Currie uncovered what initially looked like a fragment of turtle shell. On further inspection, however, he saw that it was actually a bone from the rear of a Chasmosaur’s head. Indeed, Currie could tell by the ridges along the back of the skull.
The Chasmosaurus belli, to give it its scientific name, was a herbivorous animal similar to the Triceratops. In fact, the Chasmosaurus came from the same family as that iconic dinosaur – a family known as Ceratopsids. Somewhat amazingly, every single known Chasmosaur specimen has come from Dinosaur Provincial Park.
However, the one found by Currie and his team of researchers was exceptionally rare. Indeed, while almost every previous intact specimen found had been of an adult Chasmosaur, this discovery was far too small to be another one of those.
In fact, it was a baby Chasmosaur – and an intact one, at that. Over the years, archaeologists had managed to find some bones from similar juvenile dinosaurs. However, they’d never before found a near-complete baby fossil that had remained so impeccably preserved.
“The big ones just preserve better: they don’t get eaten, they don’t get destroyed by animals,” Currie told Live Science. “You always hope you’re going to find something small and that it will turn out to be a dinosaur.”
Baby fossils are incredibly important for scientists in figuring out how the dinosaur’s bones changed over the course of its life. What’s more, without a complete sample it’s difficult to know for sure how they grew. And as researchers like Currie know only too well, individual bones can only tell us so much.
Now, because the five foot-long fossil was so impeccable, the researchers were even able to pinpoint precisely how this poor baby dino died. And the way in which the young Chasmosaur had met its end was far from glamorous. It was, moreover, probably only three years old at the time of its death.
Indeed, there was no evidence of injury or bite marks from a predator. The fossil had, instead, been buried under moist sediments. Consequently, the archaeologists determined that the most likely cause of death was drowning.
Apparently, the unlucky Chasmosaur had become trapped in a rivulet, where it eventually drowned. After its death, sediment began to bury the body. It then lay submerged for around 70 million years before Currie and his team unearthed it in 2010.
In conditions such as these, smaller bones are rare in that they often become lost in the current or otherwise displaced. But before any of that could happen with the Chasmosaur, it had already embedded itself within the sediment. And, as a result, its skeleton was almost perfectly preserved.
What’s more, the dinosaur even left a distinctive imprint upon the rocks where it found its final resting place. Indeed, the rosette-like pattern of its skin had etched itself into the rocks below – further proof of the well preserved nature of the fossil.
Yet unfortunately, the Chasmosaur wasn’t entirely intact. In fact, a cavity had opened beneath the rock at some point over the millennia, which subsequently swallowed up the skeleton’s forelimbs and washed them away. But the remains that Currie and his team discovered were, however, still far more complete than most others that had been previously found.
Don Brinkman, Director of Preservation and Research at the Royal Tyrrell Museum, enthused to CBC News, “There’s nothing else like it that I know of. It’s as close as you can get to a dinosaur mummy.”
What’s more, the extraordinary find has already helped scientists to understand more about these prehistoric creatures. For example, they now know that the Chasmosaur’s characteristic head frill changed over the course of the creature’s first 20 years of life.
Researchers also used the skeleton to determine the size difference between young and adult Chasmosaurs. Interestingly, the proportions of the animal’s body and legs remained largely the same throughout its life. The young would therefore likely have been able to easily keep up with the older Chasmosaurs.
Thanks to the almost-complete nature of the fossil, Currie and his team expect they’ll be able to better identify the other singular Chasmosaur bones they’ve unearthed in the past. So, their rare find will be a subject of study for years to come at its new home in the University of Alberta.