The Prehistoric Mustelidae Thread- Weasels, badgers, wolverines etc

A tiny skull once thought to belong to an ancient miniature cat is actually the earliest relative of wolverines, minks, otters and weasels ever found in North America, researchers say.

Corumictis wolsani, would have been tiny enough to sit in your hand, but trying to pick it up would probably not have been a good idea.

"It has these incredibly sharp teeth, sharper than some weasels today," said Ryan Paterson, who led the research while doing his master's degree at Carleton University. "It was probably a ferocious little thing, despite being the size of the tiniest weasel on the planet."

orumictis lived between 28.8 and 25.9 million years ago during the Oligocene, a time when camels, three-toed horses and rhinos roamed North America.

That makes it at least a million years older than any other weasel found in North America before and just a couple of million years younger than the oldest weasel found in Europe, the researchers report.

At that time, the area that is now modern-day Oregon was getting cooler and drier, and forests were thinning out into more open grasslands. Burrowing rodents similar to ground squirrels and groundhogs were starting to appear. That's the kind of prey modern weasels generally prey on.

"We thought there might be a connection between other things popping up that live in these open habitats and our own critter, Corumictus, coming on the scene," Paterson said.

While modern weasels have long skinny bodies that allow them to squeeze and slither into rodents' narrow burrows, the researchers have only Corumictis's skull and teeth and none of its body. So while they know it was tiny, they don't yet know if it was long and skinny.

"It could be bulkier, like a wolverine," Paterson said.