If I fits, I sits

🌿 budding · planted 2026-10-22 · tended 2026-10-22 animalscatsscience

Ahrim wondered why cats love sitting in anything they fit in. It turns out scientists have wondered too, and a few of them actually tested it.

1. A box is a safe place

Cats are both predators and prey. Out in the wild, a small cat has to hunt but also avoid being hunted. An enclosed space covers their back and sides, so they only have to watch one direction. It's the perfect spot to rest and to ambush from.

There's evidence it calms them down. In a 2014 study from Utrecht University, newly arrived shelter cats that were given a hiding box had lower stress scores and adjusted to the shelter faster in the first few days than cats without one. To a cat, a box is a small portable home.

2. Cats like it warmer than we do

The temperature a cat is comfortable at without spending energy (its thermoneutral zone) is roughly 30–36°C, much warmer than a typical room. Cardboard is a good insulator, and curling up in a tight space keeps body heat in. So a box is basically a small heated room for them. That also explains why cats love laptops, sunny spots, and warm clothes fresh out of the dryer.

3. Even a box that doesn't exist works

This is my favourite part. In 2021, researchers ran a citizen-science study literally titled "If I fits I sits". Cat owners at home put shapes on the floor:

a real square made of tape
a Kanizsa square, an optical illusion made of four "Pac-Man" shapes that make our brains see a square that isn't really there
a control shape that looks like nothing

The cats sat in the illusory square about as often as the real one, and more often than the control. That suggests cats might perceive the "box" in the illusion too, just like us. The sample was small (only a few dozen cats finished the test), so this is still a 🌿, but it's a very fun result.

It also explains why a cat will sit in a square of tape on the floor. To them, an outline might be enough to count as a "box."

So, in short

A box is safety, warmth and a hunting spot all at once. And maybe, for a cat, the idea of a box is already a box.