So you know when your cat comes up to you and it starts to look at you and it seems happy, it's purring and then it tries to make biscuits out of your body? It's so cute. It's cute because kitty loves you, but it's also painful because kitty's love is made out of little tiny knives. Why does it do that? Why?

There are theories of course! Some animal behaviorists believe that it's another way for cats to mark their territory, since paws have scent glands in them. The most popular theory, however, is that kneading is a neotenic behavior: a juvenile trait that is retained in adulthood. Because kittens knead their mother's bellies to stimulate milk production. This would explain why some adult cats also suckle whatever it is that they're kneading. However, adult wild cats do not knead. So, why have domesticated cats retained this trait?

Well, neotenic behaviors are most often found in domesticated animals, like house cats, partly because over the millennia humans have selected for traits that make animals more social, less aggressive, and generally nicer to be around. But the animals have probably also held on to some of their social baby-like behavior just because it serves them well when they're around people. Like, I don't know if you've heard this, but wild cats are not super social. They don't come up and cuddle, so much as trying to eat your flesh.

Felis sylvestris, the ancestor of all domestic cats, is a solitary hunter that only socializes with members of its own species when it's time to breed. So wild cats only developed social behaviors for two situations: one is "Hey baby why don't you come back to my burrow and we could make a little something-something", and the other is care-taking behaviors between mother-cats and their kittens. Unlike wild cats, though, domesticated cats have a lot of social behaviors as adults. Because they're not wild loners anymore: they have us to cuddle with, con treats out of, and demand food from. So their innate tendencies for snuggling with mom and hitting on the lady cats are put to good use on us. Hence: kneading, originally a behavior that kittens needed to survive, is now a way for adult cats to show that they trust you and feel safe. And if you had a soft pelt like mom you wouldn't feel so much of the... little knives.

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