It's no secret that seals and dogs have a lot in common. They bark. Their babies are called pups. They enjoy a good belly rub.
Sometimes, they even become pals.
But are they actually related biologically? The answer is: not particularly, but they're not too far from each other on the family tree of genetics.
They're both part of the group Caniformia, which means "dog-like." But then dogs branch off, along with the bear family. So seals are actually more closely related to bears than to man's best friend. We guess we can kind of see it in the claws?
There was actually debate regarding this topic within the scientific community.
Scientists figured that there was a common ancestor for all of the pinnipeds we know and love — true seals, fur seals and seal lions — but for years, they couldn't find it.
Some believed an ancient seal-like animal called Enaliarctos was the missing link. It had developed limbs with webbed back flippers. Researchers who studied biomechanics concluded these aquatic animals used both their front and back limbs to swim.
Today's fur seals and sea lions primarily use their front flippers for swimming, while true seals use their backs. The different groups evolved to use separate parts of their squishy bodies — the story checks out to us, at least.
But then, a new discovery rattled the seal evolution world!
A fossil was discovered that showed a whole new species, one that looked a lot like a giant otter.
Puijila darwini (Wikimedia/Smokeybjb)
It had webbed feet, but no flippers, allowing it to move around on land just as well as on water. In fact, Charles Darwin himself had posited that the ancestor to seals hunted mostly on land and in shallow ponds and streams. But until this fossil was discovered, the only contender was already fully flippered.
Researchers ended up naming the fossil Puijila darwini: Puijilia means young sea mammal, and dawini is after Darwin, for calling it.
So even though it's a little disappointing that seals aren't related to some kind of aquatic dog, we can at least take solace in the many dogs that look like seals, and vice versa.
Plus, giant otters are pretty cool, too.