Meet ‘Chasm’: The 75-Million-Year-Old Dinosaur Helping Scientists Bridge Evolutionary Gaps

A baby dinosaur uncovered six years ago in Alberta badlands is now providing scientists with the answers to evolutionary mysteries.

The intact skeleton of the juvenile Chasmosaurus, nicknamed ‘chasm’, is thought to be just three years old when it died, has become the anchor point for research on the species.

Paleontologists at the University of Alberta say the rare discovery has revealed surprising physical traits, and provides new understanding of the life history of horned dinosaurs, like the well-known Triceratops.

A baby dinosaur uncovered five years ago in Alberta badlands is now providing scientists with the answers to evolutionary mysteries. The intact skeleton of the juvenile Chasmosaurus, thought to be just three years old when it died, has become the anchor point for research on the species

The bones of the baby Chasmosaurus were unique in that they had remained fully intact 75 million years after death.

Researchers suspect the dinosaur may have drowned.

‘For the first time ever, we have a complete skeleton of a baby ceratopsid,’ says Professor Philip Currie from the University of Alberta, who made the 2010 discovery at Dinosaur Provincial Park in Alberta, Canada.

‘We’ve only had a few isolated bones before to give us an idea of what these animals should look like as youngsters, but we’ve never had anything to connect all the pieces,’ Currie said.

‘All you need is one specimen that ties them all together. Now we have it!’

The specimen is just over 1.5 metres long, but would have grown to five metres had it reached adulthood. And, it would have been heavier than an Indian elephant.

‘One of the greatest benefits is that we can now look at the different body proportions for Chasmosaurus as it grew up,’ Currie said.

‘We now have an anchor point with the baby that we can compare with all other specimens of this species, and from that comparison can calculate the dimensions, body weights, and ages for all other ceratopsid species.

‘We can start filling in missing pieces.’

WHAT THE SKELETON REVEALS

The bones of the baby Chasmosaurus were unique in that they had remained fully intact 75 million years after death.

The researchers suspect the dinosaur may have drowned.

Paleontologists at the University of Alberta say the rare discovery reveals surprising physical traits, and provides understanding of the life history of horned dinosaurs, like the well-known Triceratops.

The specimen is just over 1.5 metres long, but would have grown to five metres had it reached adulthood.

And, it would have been heavier than an Indian elephant.

Researchers had expected to see that a baby dinosaur of this kind would have a short ‘frill,’ the shield-like structure at the back of the head, relative to its skull.

They were surprised to find that, while the frill is broad, and squared at the back in an adult Chasmosaurus, the juvenile skeleton revealed a narrow, arched frill with a ridge down the middle.

The intact skeleton is now an anchor point for comparisons with all other specimens of this species, to calculate the dimensions, body weights, and ages for all other ceratopsid species.

The discovery of the 75 million-year-old skeleton is now allowing scientists to refine earlier research, and answer questions about the evolutionary history of the Chasmosaurus and other horned dinosaurs, like the well-known Triceratops (pictured above)

‘Unless you’ve got that basic anatomical information, you’re kind of shooting in the dark with all of these other calculations,’ Currie said.

Researchers had expected to see that a baby dinosaur of this kind would have a short ‘frill,’ relative to its skull.

The frill is the shield-like structure on the back of the Chasmosaurus’s head, and on many other horned dinosaurs, like its relative, the Triceratops.

They were surprised, however, to find that the frill was shaped differently in the young dinosaur than in the adult, Currie explains.

While the frill is broad, and squared at the back in an adult Chasmosaurus, the juvenile skeleton revealed a narrow, arched frill with a ridge down the middle.

Palaeontologists at the University of Alberta say the rare discovery reveals surprising physical traits, and provides new understanding of the life history of horned dinosaurs, like the well-known Triceratops. Research on the skeleton will continue, and Currie plans to analyse the brain case using advanced CT scanning in Japan

‘It is very different than I expected,’ Currie said.

Research on the skeleton will continue in the years to come, and Currie plans to analyse the brain case using advanced CT scanning in Japan.

‘We still haven’t plumbed the depths of the anatomical description,’ says Currie.

‘Over the next few years, I will assign different parts of the body to different students who will then focus on growth changes and their implications within ceratopsids.’

And, for the first time ever, people outside of Alberta will be able to see the skeleton while it is on display in Tokyo at the National Museum of Nature and Science.

‘Alberta has long been known as one of the centres for ceratopsian research, said Michael Ryan, one of the world’s top ceratopsian dinosaur researchers and Curator of Vertebrate Paleontology at the Cleveland Museum of Natural History.

‘The discovery and publication of the baby Chasmosaurus cements Alberta’s leadership in this area.’