A group of scientists has identified a new invertebrate species from a rare fossil found in Gaspésie's Miguasha provincial park. The species is a ctenophore, or comb jelly, a soft-bodied animal that looks like a jellyfish.
"It's a very interesting fossil, and it's revealing a lot of insights about the evolution of life," said Richard Cloutier, a paleontologist and one of the lead researchers. "It's very, very rare that we have that kind of fossil," he added.
This discovery is important because it confirms that comb jellies were among the earliest multicellular animals, giving clues about the origins of complex life forms on the planet, explained the paleontologist who works at the Université du Québec à Rimouski.
He said it supports the theory that animals evolved either from sponges or comb jellies, because it confirms that the species existed hundreds of millions of years ago, when life forms were at their most primitive.
The six-centimetre fossil was first discovered in 2017 in Miguasha, a site well known for its abundance of prehistoric fish fossils. But the specimen dates back 375 million years, from an era called the Late Devonian.
A very rare specimen
What makes this specimen unique is that the animal was preserved despite having no bones, teeth or cartilage, Cloutier said.
"Normally what we find in the fossil, it's all the hard parts," explained Cloutier. "Usually when it's a soft-bodied animal, there's nothing that could be preserved."
Hans Larsson, a paleontology professor at McGill University's Redpath Museum who was not involved in the research, confirmed the fossil's discovery was exceptional: "Imagine preserving a jellyfish for hundreds of millions of years in a rock. It's almost impossible to even imagine the odds of finding this," he said.
In fact, he said, the odds are so slim that they can be counted on someone's fingers.
Miguasha park's collection manager, Johanne Kerr, said she was very intrigued when the fossil showed up on her desk because it was very different than anything she had seen before.
So, she decided to reach out to Cloutier, and that started a quest to figure out what it was. An expert from Switzerland and one from Australia eventually also joined the research team.
Discovering that it was an entirely new species of comb jelly was really exciting and a proud moment, Kerr said. "It confirmed that the Miguasha site is really exceptional," she said.
The park, which is a UNESCO World Heritage site, has an abundance of preserved vertebrates, but finding fossils of soft-bodied species is new, she said.
"Now that we know we can find this type of fossils here in Miguasha, we'll keep an eye out for more of them," she said.
Cloutier will bring back the fossil to the Miguasha park in the coming weeks, where it will be available for other scientists who wish to examine it. It will be available for public viewing next year.