Even if you don’t share your home with a cat, you probably know from social media that cats love to get in boxes. My favorite cats-in-boxes memes show several cats sitting in boxes with the caption “Cat traps.”

But have you ever wondered why cats have this weird thing for boxes? The answer is pretty much what you’d expect: They feel safer and more secure, all tucked up in a tiny space.

Why Do Cats Like Boxes?

Some studies have found that when shelter cats are given boxes to hide in, their stress levels drop significantly. In a piece for The Conversation, veterinary behaviorist Nicholas Dodman explains that hunkering down in small, enclosed spaces is a kind of “swaddling” behavior left over from cuddling up with their moms and littermates when they were kittens.

But box sitting is more than just cute; it may be important for cats’ mental health. Dodman writes that “cats need boxes or other vessels for environmental enrichment purposes.” So please, pass those Amazon boxes along to your cats. 

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Why Do Cats Like Squares?

But it’s not just boxes. As demonstrated by the Twitter (X) hashtag #CatSquares, cats often rush over to claim a square marked off on the floor with pieces of tape. And as many a cat person has noticed, a piece of paper on your desk, table or floor is also a powerful cat attractor. 

This is peculiar. How safe and cozy can a cat feel sitting right out in the open on top of the water bill? Dodman describes it as something like the placebo effect. “This virtual box may provide some misplaced sense of security and psychosomatic comfort,” he writes.

Cats like boxes so much that they even fall for fake boxes. A team of researchers from Hunter College, CUNY, found that cats will happily sit in illusory squares.

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The Challenges of Cat Studies

But before we get into the details of that study, let’s step aside for a moment and talk about scientific studies on cats. There aren’t as many of them as you’d think based on cats’ social media popularity. The reason? Cats make extremely lousy research subjects. When researchers bring cats into the lab to test their intelligence, the cats tend to wander around, hide or just laze about, completely uninterested in what the researchers are trying to get them to do. 

David Grimm is the author of Citizen Canine: Our Evolving Relationship with Cats and Dogs. In an article for Slate magazine, he wrote that when he was researching the book’s chapter on animal intelligence, he asked Ádám Miklósi, one of the world’s top experts on the subject, about research on cat intelligence. Miklósi’s answer, according to Grimm, was, “We did one study on cats—and that was enough!”

So, the Hunter College researchers wisely decided to let the cats stay home. Instead of inviting cats to the lab, they recruited citizen scientists to test their cats at home. (It helped that this was during the lockdown phase of the COVID-19 pandemic, so plenty of people were at home with their cats, apparently getting bored with tossing catnip toys and looking for new ways to pass the time.)

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If I Fits I Sits

In the charmingly named and very clever study, “If I Fits I Sits: A Citizen Science Investigation into Illusory Contour Susceptibility in Domestic Cats (Felis silvestris catus),” the researchers tested cats to see if these notorious square sitters would be fooled by an optical illusion known as a Kanisza square. 

A Kanisza square is a visual puzzle in which Pac-Man-like circles are arranged so as to create the illusion of a square. Using paper, tape and scissors, cat owners created both real and illusory squares according to instructions sent by the researchers. And sure enough, the cats were just as likely to sit in a Kanisza square as a real one.

The study, the researchers say, confirmed previous research showing that cats are susceptible to visual illusions, which adds to the growing but still relatively meager body of research on cat cognition. The study also explored the possibility of studying cat behavior in what the paper’s authors describe as “a more ecologically valid, real-world setting.”

The study had one potential limitation. You guessed it: sample size. From an initial pool of 561 interested participants, 30 cats ended up completing the study. Maybe Miklósi was right to give up after one study and just let the cats go back to their boxes.

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