It seemed out of place, and not only because the skull of the critter, which couldn't have been much bigger than a bunny rabbit, was found under a dinosaur's fossilized foot.
"We've never found a mammal there in these rocks before," researcher Jim Kirkland told the Salt Lake Tribune. "This one skull turns out to be a complete oddball."
They were in eastern Utah, and the fossilized cranium his colleague Jennifer Cavin had stumbled upon this month may have farther reaching implications than its size implies.
First off, she stumbled on a totally new species, which has been named Cifelliodon wahkarmoosuch, according to the journal Nature, where lead author and assistant professor of clinical integrative anatomical sciences at the Keck School of Medicine of the University of Southern California published their findings.
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But the "oddball" location of the discovery also led Huttenlocker's team to the conclusion that our present-day continents may not have split apart from one another quite as many years ago as most scientists believe, according to KSL. The 130-million-year old skull is evidence that the super-continental breakup of the landmass known as Pangaea may have occurred about 15 million years later, to be exact.
Think of the Cifelliodon wahkarmoosuch as a cross between a cat and raccoon, except that the researchers believe that it was actually an egg-laying species, according to KUER. What's even stranger is that once the eggs hatched, the creatures suckled their young, like mammals.
The skull the team found was about three inches across. CT scans showed it probably had a small brain and enlarged olfactory bulbs, which meant a keen sense of smell — one of the many precursors to modern mammals it exhibits, according to the Tribune.
And it is believed to have been covered in hair. So while they may not have been pretty, the diminutive critter might fill in a substantial portion of the missing links in mammals' evolutionary tree — even though they're not all the way mammal.
They're classified as Hamamiyidans — which thrived before the rise of modern mammals, which took place after the giant asteroid slammed into the earth, killing off most of the dinosaurs 65 million years ago, according to Live Science.
Huttenlocker and his team provided evidence that Cifelliodon is closely related to other species from the Cretaceous period (145 million to 66 million years ago) that have been found in northern Africa and Madagascar, according to Nature.