Bet you can't work out what this is about from the thread title. But it involves cats obliquely, so someone is bound to click on it.
According to this interesting article
, there are about as many neurons in the human digestive system as there are in a cat's brain, about 100 million. There's a lot going on down there. We tend to think of the brain being in charge of the body, but really, it's just at the head of a committee.
(Don't worry cat lovers, this doesn't actually mean our guts are as smart as a cat. The neurons are organised very differently. There are parallels between the two, both can be very demanding, but your favourite pet is in no danger of being superseded.)