Mastodon migrations north offer clues about today's animal movements: study

WHITEHORSE — The migration of extinct mastodon herds to Yukon and Alaska during warm periods between ice ages could hold clues and warning signs for today's animals moving north during a warming climate, says a new research paper.

The paper from Hamilton's McMaster University, published Tuesday in the journal Nature Communications, says mastodon herds that migrated north during the warm periods were less genetically diverse, which made them more vulnerable to extinction.

Mastodons, similar to today's elephants and extinct mammoths, roamed much of North America, including parts of Mexico. Mastodons went extinct about 11,000 years ago along with mammoths, large-toothed cats, giant beavers and western camels.

Emil Karpinski, a paleontologist at McMaster's Ancient DNA Centre, said the report is the result of six years of research that examined the fossil bones and teeth of more than 30 different mastodons.

He said the research showed mastodons migrated north several times during periods between ice ages when the Earth warmed, but didn't survive when ice ages returned.

"Mastodons were much more at home in these warmer, wooded wetland habitats with an abundance of shrubs and trees like spruce and pine for them to eat," Karpinski told a panel discussion involving about a dozen mastodon experts.

"We wanted to see, which is kind of the end hope of all this research, if what we learn about these animals could be applied to present-day species," he said.

"We're observing very similar travels in species like moose, snowshoe hare, beavers, not just ones in the Arctic, but also various birds, fish and other species that are rapidly moving northward in response to climate warming."

Karpinski said the research indicates the mastodon herds that migrated north were less genetically diverse and were more susceptible to extinction.

Grant Zazula, a Yukon government paleontologist and one of the report's authors, said the research shows mastodon herds migrated north more than once with the same disastrous results.

He said the northern mastodons were decimated with the arrival of an ice age 250,000 years ago and were also wiped out by a second ice age about 100,000 years ago.

"Their populations would have peaked about 100,000 years ago and that's when climates were essentially as warm as they are today and the environment looked very similar to today's environment," he said.

Zazula said mastodons were not equipped to survive the colder climates of the ice ages.

"What this is showing us is those populations kind of at the frontier of migrations and range extensions really lack genetic diversity," he said. "It doesn't take very much to wipe them out. It could be a change in climate. It could be hunting. It could be disease."

— By Dirk Meissner in Victoria.

This report by The Canadian Press was first published Sept. 1, 2020.

  

The Canadian Press