Victoria researcher links tail evolution of species separated by 300 million years

Weaponized tails of dinosaurs, extinct armadillo species connected by ‘convergent evolution’

A Victoria researcher has helped to fill in the gaps in a dinosaur ‘tail’ as old as time.

Royal BC Museum paleontologist Victoria Arbour and Lindsay Zanno of the North Carolina Museum of Natural Sciences set out to understand why two armoured species – separated by more than 300 million years of evolution – developed similar-looking weaponized tails.

Both Glyptodonts – a group of extinct armadillo-like mammals — and Ankylosaurs – large dinosaurs – have unusual clubbed “sledgehammer-like” tails, most likely used “as weapons of intra-specific combat or inter-specific defense.”

“That’s a really weird structure to evolve,” Arbour told Black Press Media. “It’s a really uncommon kind of weapon. So I was really interested in learning a bit more about why these two groups evolved such a similar structure.”

Ankylosaurs and glyptodonts both evolved similar armoured bodies with weaponized tails, but they were separated by over 300 million years.

RELATED: Researchers ponder why new dinosaur species had feathers but could not fly

Using statistical modeling and data about the two animals’ anatomy, the researchers found evidence for strong ‘convergent evolution’ – the process of unrelated groups of animals evolving similar looking body shapes. It usually means “similar selective pressures have shaped their bodies over time” according to Arbour.

Specifically, the two animals became large and herbivorous before evolving the rare tail weapons, and developed stiff tails before the tip was enlarged into a wrecking-ball-like structure.

“We showed that the way in which they evolved their tail club over time was actually really similar,” Arbour said. “We found that they were really strongly convergent, more than we expect [to happen] by chance.

The researchers speculate that ‘tail weapons’ are rare because of the stiff backbone needed to carry them.

“It seems like there’s just kind of a cascade of features that have to be in place for this thing to evolve,” said Arbour. “And understanding why that is, is still unresolved.

There are more questions than answers as we go into the future.”

RELATED: First B.C. dinosaur skull discovered near Tumbler Ridge



nina.grossman@blackpress.ca

Like us on Facebook and follow us on Twitter

Just Posted

‘More animals could have a chance:’ Victoria Humane Society in desperate need of a home

Animal rescue currently has 163 animals in foster and volunteer homes

Free-B Film Festival celebrates 20th anniversary

Head to Victoria’s Beacon Hill Park to see some family favourites on the big screen

Join North Saanich invasives removal and experience three key benefits

Friends of North Saanich Parks says July 27 clear-up will be rewarding as well as green

Central Saanich accused of not following Climate Emergency declaration with urgent action

Motion to research climate response options and costs rejected then rescheduled in tense meeting

Esquimalt gives six-storey rental complex the green light

A new apartment building is set to go up on Admirals Road

Rich the Vegan scoots across Canada for the animals

Rich Adams is riding his push scooter across Canada to bring awareness to the dog meat trade in Asia

A year later, ceremony commemorates victims of the Danforth shooting

It’s the one-year anniversary of when a man opened fire along the bustling street before shooting and killing himself

Japanese Canadians call on B.C. to go beyond mere apology for historic racism

The federal government apologized in 1988 for its racism against ‘enemy aliens’

B.C. VIEWS: NDP pushes ahead with Crown forest redistribution

This isn’t the time for a radical Indigenous rights agenda

Two dead in two-vehicle crash between Revelstoke and Golden

RCMP are investigating the cause of the crash

Ottawa fights planned class action against RCMP for bullying, intimidation

The current case is more general, applying to employees, including men, who worked for the RCMP

Alberta judge denies B.C.’s bid to block ‘Turn Off the Taps’ bill

He said the proper venue for the disagreement is Federal Court

Most Read