508-million-year-old bristle worm fossil found in B.C.
A fossil species of bristle worm has been discovered at the 508-millionyear-old Marble Canyon site in B.C.’s Kootenay National Park.
The worm, found by researchers from the Royal Ontario Museum and the University of Toronto, is called Kootenayscolex barbarensis.
“It’s a totally new species to science,” said Karma Nanglu, a PhD candidate in the department of ecology and evolutionary biology at the University of Toronto.
“It’s really small, and so it’s a lot smaller than the two best known (bristle worms) from the Burgess Shale. It’s about 21/2 centimetres in total length.”
The fossil, which must be viewed through a microscope, is one of the best preserved fossil species they’ve found in the area.
It’s helping scientists better understand annelids, a group of animals that includes present-day leeches and earthworms. The early evolutionary history of annelids, in particular the origin of their heads, has a relatively poor fossil record.
Nanglu said Kootenayscolex barbarensis is unlike any other bristle worm that’s been studied due to its more complex head.
“Previously all of the Burgess Shale (bristle worms) were thought to have a relatively simple head,” he said. “It’s pretty much similar to the pattern that we would expect if you look at the modern forms and try to trace back what their early ancestor might have looked like.
“This (bristle worm) is a little bit different.”
The fossil also provides insight into its role in the food chain.
They found sediment in the gut that suggests the worms played an important role by recycling organic material back to other animals that preyed on them — similar to their present-day relatives.
The research was published Monday in the journal Current Biology.
The Marble Canyon fossil site, home to at least a dozen new species, was stumbled upon by researchers in 2012 in Kootenay National Park as they worked at the nearby Stanley Glacier site.
It’s believed the area and its fossils will further the understanding of animal life during the Cambrian Period, when most of the major groups of animals appear on the fossil record.