New Canadian research into 500 million-year-old carnivore fossils has revealed an early ancestor of modern-day squids and octopuses, solving the mystery surrounding a previously unclassifiable creature.

"This is significant because it means that primitive cephalopods were around much earlier than we thought, and offers a reinterpretation of the long-held origins of this important group of marine animals," Martin Smith, University of Toronto and Royal Ontario Museum paleontology PhD student, said in a release.

Quirks & Quarks Listen to Bob McDonald's interview with study co-author Martin Smith from the University of Toronto, from the May 29th edition of Quirks & Quarks.

Smith and University of Toronto and Royal Ontario Museum paleontologist Jean-Bernard Caron published their findings in Wednesday's peer-reviewed journal Nature.

Up until the mid 1970s, paleontologists only had one fossilized Nectocaris pteryx to work with, but it was not a good enough specimen to classify the animal as being a precursor to a specific sea creature.

Over the course of the past three decades, scientists have discovered 91 new Nectocaris pteryx fossils at the Burgess Shale Formation in the Canadian Rockies, one of the world's most famous fossil sites.

A joint study of these two- to five-centimeter-long fossils by university and museum researchers shows that Nectocaris was kite-shaped and flattened from top to bottom. It had large, stalked eyes and a long pair of grasping tentacles, which the researchers believe helped it capture prey.

"Fossils like Nectocaris help us to map out how the groups alive today might be related, and how they evolved," said Smith. "This tells us something about how biodiversity originated in the past, and helps us to understand the rich tapestry of life today."