Look at two shapes. One is round and soft, like a cloud. The other is sharp and jagged, like broken glass.

Now someone tells you that one is called “bouba” and the other is called “kiki”. Which is which?

You probably did not have to think. Bouba is the round one. In a study of people who speak 25 different languages, about 72% made the same call.

It is strange when you stop to think about it. Both words are made up. Nobody taught you what they mean. And still the answer arrives before the question is finished.

Where could the match come from?

One guess comes from 2001, when the neuroscientists V. S. Ramachandran and Edward Hubbard made the two words famous. Say “kiki” slowly. Your tongue taps the roof of your mouth in a sharp, quick way, a little like the jagged line looks.

If that is the reason, the match lives in speech, and it belongs to people. But the evidence is awkward. Three-day-old chicks made the match in a 2026 study, which ScienceBlog covered in February, and chicks do not talk. Chimpanzees and gorillas did not in a small earlier test.

So a team at the University of Parma tried an animal that lives among human speech but does not use it. They tried dogs.

What they did

The study was published in Proceedings of the Royal Society B on 14 October 2026 and tested 70 pet dogs.

Each dog faced two screens, one showing a round shape and one a spiky shape. A speaker played “bouba” or “kiki”. The owner held the dog still for 20 seconds while a camera filmed.

It is worth pausing on the word “looking”. The team did not track the dogs’ eyes. An AI program worked out which way each head was pointing, and a dog counted as looking when its head faced a screen.

For 19 of the dogs, the owners wore headphones playing rock music. They could not hear the word, so they could not nudge their dog without knowing it.

What the dogs did

Dogs looked more at the round shape when they heard “bouba”, and more at the spiky one when they heard “kiki”. The dogs with headphoned owners did the same.

The team shared its open data, and it holds a detail the paper does not spell out. In the first group of 51 dogs, every single dog spent a bigger share of its looking time on the round shape during “bouba” trials than during “kiki” trials.

Now look at how big “longer” is. The dogs only looked at the screens for about 6 of the 20 seconds. On “bouba” trials, the round shape got about 3.4 seconds and the spiky one about 2.6. On “kiki” trials it flipped, with about 2.1 seconds for round and 3.6 for spiky.

That is a shift of about one second. Small, but it went the same way for every dog.

Their first glance did not follow the sound. The paper says it went to both shapes about equally. The pattern only appeared over the full 20 seconds.

The spiky twist

The dogs also had a pull of their own. In the first group, they were quicker to look at the spiky shape, whatever sound was playing.

Here is what the Parma press release says, translated from the Italian:

  • Dogs look more at the round shape for “Bouba” and at the spiky shape for “Kiki”.
  • This supports the idea that the effect is part of a wider set of sound-and-sight matches shared across species, and not a purely human trait tied strictly to language.
  • In children and chicks, the effect seems strongest for linking round shapes with “Bouba”. Dogs may have a different built-in leaning.
  • For now, no one can say if the difference comes from the species, from each dog’s experience, or from the objects dogs usually deal with.
  • Future studies will check if the match shows up early in life, how widespread it is across species, and whether living with people made it stronger.

What it does not show

This does not mean the dogs understood anything. “Bouba” and “kiki” mean nothing, and that is the point of using them.

The group was also narrow. These were medium to large dogs with medium-length snouts, tested in one lab in Parma. The paper says more studies are needed to learn how the effect begins and what it is for.

Try it yourself

You can run a small version at home, and you do not need a dog.

  1. Draw one round, cloud-like shape and one sharp, spiky shape.
  2. Ask a friend or family member, one at a time so nobody copies: “One of these is called bouba and the other is kiki. Which is which?”
  3. Say nothing else.
  4. Count how many pick round for bouba.

I tried it at a family gathering while writing this piece. I asked 27 people, and all 27 said the round shape was bouba.

That is higher than the 72% from the 25-language study, and it is worth keeping in proportion. A family party is not a lab, and I cannot rule out that people overheard each other. Your own group may split differently. The match is common, not universal.

Then think about the dog. If a chick and a dog both seem to link “bouba” with something round, maybe words did not invent the link. Maybe they borrowed one that was already there. The dogs do not prove it. They make it a little harder to dismiss.