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If we could find one silver lining to the pandemic, it's that we have come one step closer to answering some of the questions about our feline friends.

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Thank you to Magic Spoon for sponsoring today’s episode!

Go to and use the code SciShow at checkout to get $5 off any order. [♪ INTRO]. Our cats do a lot of amusing things.

It’s what makes them so endearing and gives them control over half of the internet. And though humans have been with their feline overlords for at least 10,000 years, we are still learning new things about them all the time. Like, for example, how do they know to barf in exactly the spot you’re going to step in on your way to the bathroom late at night?

And why do they like to sit in boxes and on things that just resemble boxes, like neatly folded t-shirts and laptop keyboards? Well, thanks to all the free time everyone had in the summer of 2020, scientists are much closer to finally solving at least that particular age-old mystery. This research done with the help of volunteer cat owners not only tells us how cats respond to illusions, but it also sets us up to understand cats better in general.

And it all boils down to this: If I fits, I sits. Every cat owner knows that cats love to sit in boxes. It’s a cat thing.

There’s probably a practical reason they like to do this. The enclosed space of the box makes them feel less vulnerable, and that can help reduce stress. But it isn’t just boxes; it works with rectangles in general!

Like, if you just tape off a rectangle on the floor, cats will go and sit right in the middle of it. So, scientists were curious about this behavior and they took the question even further. In a 2021 publication, researchers studied this cat behavior using a “Kanisza square,” which is four Pacman shapes defining the contours of a square.

When we look at a Kanisza square, our brains fill in the gaps, creating the illusion of a complete square. The ability to perceive an object that we can only see a section of can help us understand the world, even if our brains sometimes play tricks on us. And the researchers discovered that cats really didn’t seem to prefer a real square over a Kanisza square.

Just like people do, the cats perceived the Kanisza square as if it was a complete square. The ability to fall for an illusion involves some important cognitive skills. And cats could only have come to this conclusion of what the image most likely was based on past experiences and their own preconceived notions about squares.

Studying how different animals perceive objects can help us understand if they experience the world similarly to humans, or if their brains do things differently. And citizen scientists were able to collect this information remotely during the pandemic, on their cats’ home turf! They gathered observations of their own cats in an “ecologically relevant” setting.

By which they mean, in cozy homes full of empty boxes. This home environment was especially important for this study because cats do notoriously poorly in laboratory settings. A thing you could probably guess if you have met a cat.

A stressed cat isn’t a very reliable subject because its behavior can be influenced by its state of mind. But when a cat is in its home with some food in its bowl and a few human faces available to show its backside to, it tends to model its more natural behavior. So, in what they believe is the first citizen science study involving cat behavior, scientists recruited cat owners to take part in this experiment.

The cat owners were taught how to present their pets with the stimulus, one of six randomized shapes to put on their floors, and how to avoid doing something that might affect the results, like interacting with the cat during the experiment. In other words, they were taught to be scientists! Now, because this study didn’t take place in a lab, the results are not perfect.

But given, like, how cats are, at-home experiments like this one may be a better way to give scientists preliminary information about cat behavior in particular. So, projects like this could help scientists figure out exactly what they’re looking for before moving on to a more controlled environment like a laboratory. And as for the research itself, well, it seems to suggest that cats, like us, can be fooled by illusions.

And that brings up some interesting questions. Like how much does domestication have to do with the housecat's susceptibility to illusions? Would a tiger sit in a giant Kanizsa square?

Further research, but probably not the kind done in people's houses, could help us understand if the way a cat sees the world has been influenced by the thousands of years the species has spent with people. And in the meantime, let’s just be glad that this novel study also helped our feline overlords get just a little closer to their ultimate objective: total domination of the internet. And am I complaining?

No. In that scenario, everyone wins. And speaking of boxes, if you loved grabbing a fun box of cereal for breakfast as a kid, you might love today’s sponsor, Magic Spoon.

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You can use the promo code [SciShow] at checkout to get $5 off any order. Thanks so much for watching, and thanks to Magic Spoon for sponsoring this episode of SciShow. [♪ OUTRO].