Animals photo

So, here are the rules: To answer, follow us on Twitter and tweet at us with the hashtag #mysteryanimal. For example:

Hey @PopSci, is the #mysteryanimal a baboon?

And then I might say “if you think that’s a baboon, perhaps you are the baboon!” But probably not, because this is a positive environment and all guesses are welcome and also this is not a very common animal so guess whatever you want!

The first person to get it right wins! We’ll retweet the answer from @PopSci, and also update this post so your amazing animal knowledge will be permanently etched onto the internet. Show your kids! Your dumb kids who thought that was a baboon!

Update: We have a winner! @sqwerin correctly guessed that this is a water opossum, Chironectes minimus, which is otherwise known as a yapok. The water opossum is a marsupial native to Latin America, from southern Mexico through the northern part of South America. It’s much smaller and sleeker than the opossums we’re familiar with here in North America (namely the hideous yet impressive Virginia opossum), but has the same facial structure and some of the same habits.

That said, the water opossum is unusual in lots of ways! For one, it is the world’s only living aquatic marsupial. Marsupials aren’t afraid of the water and many are fine swimmers, but none spend the majority of their time in the water besides the water opossum. It has a bunch of adaptations to deal with a life in the freshwater streams and ponds in which it’s found; it has webbed back feet, its fur repels water and helps keep it buoyant, and its pouch actually seals shut to keep young dry while the mother is swimming. (The male has a waterproof pouch, too, but doesn’t keep young in it; its purpose seems to be keeping the male’s genitalia dry.) Its creepy, oddly human-like front feet are used to grab food, mostly crustaceans.

The water opossum isn’t particularly rare. It’s nocturnal, and its population is shrinking a little bit due to deforestation and water pollution, but it’s listed as Least Concern, so hopefully you’ll be able to see its weird little hands for awhile yet. Hi water opossum!