5 Facts About Animals' Brains That Will Make You Say, "IDK How To Feel About This"

Squids have doughnut-shaped brains.

(Note: this photo is not of a giant squid. Pictures of giant squids in their natural habitat are hard to come by! Please accept this cute photo of a regular squid instead.)

Soo giant squids have brains the shape of doughnuts. Not only that, but their esophagus runs directly through the hole in their brain. Because of this, squids have to bite their food into small pieces so the meal can fit through the esophagus. If the food is too big, it can scrape against their brain and cause damage. :(

Leeches have 32 brains.

A leech's internal structure is divided into 32 separate segments, and each of these segments has its own brain. In addition to that, every leech has nine pairs of testes — but that's another post for another day.
Sea squirts (I know — just, why?) eat their own brains.

The life of a sea squirt is as follows: it comes into this world as an egg that quickly turns into a tadpole-looking thing. It has one eye, a spinal cord, a tail, and a primitive brain that helps it move around. Once it finds its forever home (ocean floor, rock, boat), it attaches itself to said home. It then proceeds to eat its own brain, absorbing its tadpole-like body, and eventually turning into this creature.
An ostrich's brain is smaller than its eyeball.

So, one ostrich eyeball is the size of a billiard ball (around two inches in diameter). Now imagine two of those in an ostrich's head. Its eyeballs are so large that there is only a little room for its brain. So because science is science and evolution is weird, an ostrich's brain is smaller than its eyes — which makes sense considering it runs in circles to "escape" from predators.
Starfish don't have a centralized brain.

The starfish's anatomy is super fascinating. Starfish use sea water (instead of blood) to pump nutrients throughout their bodies. And its central nervous system is distributed throughout its legs (or arms, who am I to say?), so it technically doesn't have a localized brain.