Mollisonia plenovenatrix preserved in dorsal view, showing the large eyes, the walking legs and the small chelicerae at the front. Alberta’s famed Burgess Shales have yielded another ground-breaking fossil find — this time the oldest known ancestor of today’s spiders and scorpions. (Jean-Bernard Caron-Royal Ontario Museum)

‘Staring at me:’ Oldest known spider ancestor found in B.C.’s Burgess Shale

‘I turned my head to the right and I see this glowing light coming from this rock’

Tiny eyes blinking at him from the rockface of the Burgess Shale near Field, B.C., drew Jean-Bernard Caron to the fossil of the oldest known ancestor of today’s spiders and scorpions.

“I was sitting there along the quarry and I turned my head to the right and I see this glowing light coming from this rock,” he said. “Two eyes, almost staring at me.”

The eyes turned out to belong to a 500-million-year-old specimen of Mollisonia plenovenatrix — so well preserved that Caron and his colleague Cedric Aria were able for the first time to definitively place the long-gone beastie at the root of a family tree that now boasts thousands of branches.

It was only thumb-sized, a scurrier of ancient sea bottoms. Still, the two paleontologists from the Royal Ontario Museum say it would have a been a fierce predator.

ALSO READ: Epic animal fossil discovery in Kootenay National Park

Large eyes spotted prey. Long limbs propelled it across the sediments. Its head was like a modern multi-tool with limbs that could sense, grasp, crush and chew.

The tiny pair of structures in front of its mouth really got Caron and Aria excited.

Those same pincers can be seen on all members of the family Chelicerata. That’s 115,000 different species, and here was their progenitor.

“I was really excited about this,” said Caron, who published his findings Wednesday in the journal Nature.

“Those fossils tell us about the origin of key innovations in animal evolution. It’s important to understand how they happen. Because when they happen, there is often an explosion of life that is the consequence.”

Intriguingly, the species was clearly some distance along its evolutionary path, well-adapted to its environment and breathing through thin gills layered like the pages of a book.

“This discovery tells us that at the time of the Cambrian they were already there,” Caron said. “They probably evolved earlier than that.”

That means there’s probably another, even older ancestor out there — maybe waiting in the same Burgess Shale of southeastern British Columbia.

Those rocks are renowned the world over for their wealth of fossils from the middle Cambrian period, a time when the Earth’s biodiversity exploded. What sets Burgess specimens apart is the clarity with which the soft parts of the animals are preserved.

“I feel like a boy in a candy store,” Caron said. “There are a lot of candies to choose from and the question is which one I’m going to pick and describe first.

“We could work for decades there and still feel we haven’t scratched the surface. There’s still a lot ground we haven’t covered.”

Look for the eyes, said Caron.

“The eyes are very reflective. It’s very striking. Many fossils that we discover in the rocks, the first thing you see are the eyes, like shiny spots in the rock.”

Bob Weber, The Canadian Press

Like us on Facebook and follow us on Twitter.

Just Posted

International film series returns to Chilliwack this fall

The Chilliwack International Fall Film Series at Cottonwood 4 Cinemas runs Oct. 2 to Nov. 6

Grand opening of Molson Coors Fraser Valley Brewery at Chilliwack cause for celebration

Ribbon-cutting with dignitaries, Molson brass and family marked the official grand opening

Two more on witness stand accuse former Chilliwack youth leader of sexual touching

BC Supreme Court justice rules similar fact evidence allowed in trial of Codie Anderson

East Coast comedian Ron James bringing ‘Full Throttle Tour’ to Chilliwack Cultural Centre

James is at work on the first draft of his first book, ‘All Over the Map’

Multiple accidents on Highway 1 slowing morning commutes

One accident just past 232 Street in Langley, second is just East of Bradner Street in Abbotsford

VIDEO: Drone footage documents work to free salmon at Big Bar landslide

Video shows crews working to remove rocks and wood, and transporting salmon by helicopter

Defense says burden of proof not met in double murder case against Victoria father

Closing statements begin in trial for man accused of killing daughters Christmas 2017

B.C. dog breeder banned again after 46 dogs seized

The SPCA seized the animals from Terry Baker, 66, in February 2018

Surrey mom allegedly paid $400,000 for son in U.S. college bribery scam

Xiaoning Sui, 48, was arrested in Spain on Monday night

Three dogs found shot dead in Prince George ditch

The three adult dogs appeared to be well cared for before being found with gunshot wounds, BC SPCA says

Vancouver police could be using drones to fight crime by end of year

The police department has already purchased three drones, as well as three others for training

B.C. party bus company to be monitored after 40 intoxicated teens found onboard

Police received tip teens and young adults were drinking on party buses and limousines in Surrey

B.C. cabinet minister denies that Surrey mayor’s friend attended government meeting

Surrey councillor questions Vancouver businessman Bob Cheema’s involvement in official meeting

Rick Mercer calls out Conservative candidate in B.C. for fake meme

‘Not true. All fake. Please Stop,’ tweeted Rick Mercer in response

Most Read