Cats May Be Aware of Their Body Size, Suggests Study of Their Famously ‘Liquid’ Behavior

Cats’ remarkable ability to slip through tight spaces has earned them internet fame and offered their owners endless entertainment. Some pet parents even joke that their felines are more liquid than solid. But what do cats think about the state of their own bodies, if anything?

One researcher was determined to find out. In a paper published in September in iScience, Péter Pongrácz reports that cats seem to be aware of their body size—but they only use this awareness in certain situations.

Pongrácz is an ethologist—or researcher of animal behavior—at Eötvös Loránd University in Hungary. In the past, he’s studied body size awareness in dogs, using experiments to show that the creatures have some understanding of how big they are.

For his 2019 dog study, Pongrácz asked owners to bring their canines into a laboratory, where he’d set up a wood panel with an adjustable rectangular hole. When the size of the opening was large, the dogs happily passed through to rejoin their owners on the other side. But when Pongrácz made the hole smaller, the pups began hesitating or even refusing to pass through it. To Pongrácz, this seemed to indicate that they understood they might not fit.

He wondered if cats might have a similar understanding of their body size. For the feline study, he brought his experimental setup to the animals’ homes to avoid the stress of relocating them to the lab. Even then, some cats couldn’t be bothered with walking through the rectangular holes in Pongrácz’s slabs of cardboard—despite their owners sitting on the other side, encouraging them with treats or toys, several cats were eliminated from the study for walking away. Thirty cats did complete the task, however, providing data for Pongrácz’s analysis.

Like with the dogs, Pongrácz adjusted the size of the opening to see how the cats would react. When the opening was large, many cats waltzed right through without hesitation. But when he shrank the opening’s height, keeping the width more comfortable, the four-legged participants began to hesitate.

Under the opposite condition—when Pongrácz shrank the width but kept the height comfortable—most cats never hesitated to cross through, no matter how narrow he made the opening. In this dimension, the felines “don’t use body awareness,” Pongrácz tells Science’s David Grimm.

“They’re basically like liquids,” he adds. Instead of relying on body awareness, the felines used trial-and-error for gaps with a narrow width.

This finding makes sense in the context of cats’ wild origins. In the wilderness, crouching down to squeeze through a short hole might make them more susceptible to danger by reducing their view of what’s on the other side, Pongrácz tells Science News’ Andrea Tamayo. In a domestic situation, where cats are largely safe from potential threats, their continued hesitation seems to indicate they are aware of their own body size—or, at the very least, their height.

Why do cats only use their body size awareness in some situations, while dogs seem to use it all the time? Researchers don’t know for sure, but the differences between the two species may boil down to anatomy. Cats are simply more malleable and flexible than dogs, so they just don’t have to worry about whether they’ll fit through an opening as much as dogs do, says Ivan Khvatov, a psychologist at the Moscow Institute of Psychoanalysis who was not involved with the research, to Science.

One aspect the study failed to explore was whether cats act differently around tight spaces based on their reason for passing through, as Sridhar Ravi, an aerospace engineer at the University of New South Wales in Australia who was not involved with the research, says to Science News. For instance, if a cat is pursuing a mouse, they might hesitate to squeeze through a small space, because they know they are moving quickly and want to avoid getting injured, he adds.

“That is something the study could have commented on or even experimented [with],” Ravi tells Science News.

Cats and dogs are not the only creatures to exhibit body awareness. Bumblebees, bluestreak cleaner wrasse, Asian elephants, hooded crows, rat snakes, birds called budgerigars and ferrets also seem to understand their own dimensions, suggesting that humans are not unique in this regard.

Sarah Kuta | READ MORE

Sarah Kuta is a writer and editor based in Longmont, Colorado. She covers history, science, travel, food and beverage, sustainability, economics and other topics.