Sheep can remember 50 faces, but only 50. Wait, so what happens to face #1 when face #51 comes along?
Well, it takes more than 200 neurons for a sheep to simultaneously record the faces of its herd. Over time, they use more and more of these neurons to encode faces, until it reaches max-faces, like anyone trying to hold their own at a big dinner party. Eventually, there are no new friends to make because you simply can’t remember all of them. At that point, according to Scientific American:
“The recollection of fellow sheep weakens slowly but progressively over time… with the memory of a specific individual fading first into a generalized category of familiar individuals before it is forgotten completely. Indeed, the face-processing system at work in the sheep brain is analogous to the mechanism by which humans remember and recognize individuals over long periods.”
The process of remembering and forgetting in humans works the same way. It’s face specific. Just how similar that makes the information that humans remember and the information that sheep remember is unclear. What is clear is that they know 50 more faces than you probably gave them credit for.
Just how smart are our fluffy friends? Really, we’re not clever enough to know how, but we do know that even if sheep can’t recognize themselves in a mirror test—even though that test definitely can’t tell us everything—they can be taught to recognize human faces in photographs.
Anyways, isn’t 50 faces quite a lot?