Ancient Fish Species Discovered in Nova Scotia

Thursday, May 17, 2018

Fish fossils found at Blue Beach, N.S., can help fill in evolutionary gaps between fish and four-legged creatures, such as this early tetropod which was fish-like, with tail fins, gills and up to eight fingers. (Richard Hammond)

A species of fish that lived 350 million years ago has been discovered in Nova Scotia, casting new light on a little-understood time period.

The discovery was made in 2015 by Jason Anderson, a vertebrate paleontologist at the University of Calgary, at Blue Beach, N.S., and announced Wednesday.

Chris Mansky, fossil researcher and curator of the Blue Beach Fossil Museum, says Anderson located the skull of the early Carboniferous fish and was able to compare it to the family tree of better-known relatives of the fish.

Mansky says the research of Anderson and his team show the fish’s lineage appears to be a survivor of the Devonian extinction, which contradicts the notion that the extinction wiped out that group.

The species — Avonichthys manskyi — was named after the nearby Avon River and for Mansky, in honour of his years of collecting and exhibiting the fossils of Blue Beach.

The findings were published Wednesday in the United Kingdom’s peer-reviewed Royal Society Open Science journal.

Mansky said the fish is unique, and the discovery means that researchers may start looking at evolution differently.

“It paves the way for future researchers. It gives us new theory and it upsets the old theory,” he said.

“The old politics of the Devonian extinction is very much in debate. This is essentially a road map of new opportunities for young researchers who can work at this for many years… The actual shape and patterns of evolution are not so clear. To gain an understanding of how it really was, we still have a lot of work.”

A skull of the early Carboniferous fish, found in Nova Scotia, is seen here. (Source: Royal Society Open Science)

Anderson said he came across the specimen by chance during a stroll on Blue Beach.

“There’s nothing extraordinary about that moment at all. I was just literally walking along looking at the ground, kicking rocks, and I found one that was the shape of a bone. I didn’t even know it was a fossil,” said Anderson from a conference in Ottawa.

“It wasn’t until a few months later that I actually put it under a microscope.”

Anderson said there are many lingering questions, including how many of these fish species survived the extinction.

“Or is it an artifact of preservation, the fact that we just don’t have very many fossils of this age? Now that we’re actually actively exploring, will we start filling in more of these lineages? Or is this one real lucky one that managed to squeak through?” he said.

“We need to get a better idea of what other fish lived at that time, and in other places at the same time, and that will tell us more about how severely vertebrates were impacted by the mass extinction.”

He said that research has already taken him back to Blue Beach.

The site where the fossil was located is on the Bay of Fundy’s Minas Basin, which has the highest tides in the world. The sea has eroded into the shoreline, uncovering 350-million-year-old fossils.

“This highly dynamic environment, over four kilometres in length, creates unique opportunities for discoveries that would otherwise be very difficult to make,” said Mansky.

“Nature does the digging here.”

Mansky said his museum has a collection of roughly 10,000 fossils, weighing roughly 100,000 pounds. He described it as “busting at the seams,” making it impossible for researchers to examine and catalogue the material properly.

“These were findings and a paper generated from a single fossil, so we can only imagine how much more there is to be learned in the upstairs of Blue Beach Fossil Museum,” said Mansky.

“There needs to be a new paleontology centre developed here to establish a permanent foothold for this fossil collection. It’s a world-class collection and right now we have a private home-based, ma-and-pa museum. The collection has outgrown its home.”

Conrad Wilson and Jason Pardo were also authors of the article published Wednesday.