Dogs Match 'Bouba' to Round Shapes and 'Kiki' to Spiky Ones, Just Like Humans
Dogs seem to agree with humans that 'bouba' is round and 'kiki' is spiky
A University of Parma team led by animal behaviorist Eleonora Biffi tested 70 domestic dogs on the classic bouba/kiki effect, first described in the 1920s. With screens and speakers on either side, dogs heard a human voice say 'Bouba' or 'Kiki' while two shapes swapped positions; GoPro footage fed to an AI tracked their gaze. The dogs looked significantly more at the rounded shape for 'Bouba' and the spiky shape for 'Kiki', even when owners wore headphones playing rock music to block any cues.
It could be hypothesized that the dogs were influenced by the owners' unintentional cues. However, since humans typically show a stronger preference for rounded or curved shapes rather than spiky ones, this is unlikely.
- donjapan22
This is a fascinating article and I’m not casting shade but more of a curious question: If humans are the ones that generally associate this sound with that thing, knowing dogs are very observant of us, how do we know the dogs aren’t just copying what we are unknowingly exhibiting toward them throughout their entire lives? I have no idea how you’d pull that out of the stats though. Maybe you could find languages that have different sounds for round and spiky and compare dogs from those households to English speaking households (or rather languages with k’s for spiky and b’s for round)
- gste
I think objects with these shapes make similar sounds in the real world. Sharp shapes make percussive sounds. Round shapes make softer sounds.
Dog's have very good hearing, and their hearing must help them to model the world around them, to understand what different objects in the world are.
So I think it's less about linguistics and more about our audiovisual mapping of the physical world.
Then again, that must be where the origin of language evolved from in the first place.
- dang
Related. Others?
Evidence of the bouba-kiki effect in naïve baby chicks - https://news.ycombinator.com/item?id=47105198 - Feb 2026 (107 comments)
Which is "Bouba", and which is "Kiki"? [video] - https://news.ycombinator.com/item?id=46572742 - Jan 2026 (23 comments)
Bouba / Kiki Effect - https://news.ycombinator.com/item?id=45320327 - Sept 2025 (2 comments)
Bouba/kiki effect - https://news.ycombinator.com/item?id=40699583 - June 2024 (170 comments)
Bouba/Kiki Effect - https://news.ycombinator.com/item?id=27885703 - July 2021 (94 comments)
Bouba/kiki effect - https://news.ycombinator.com/item?id=8372550 - Sept 2014 (1 comment)
- DoctorOetker
I too would associate "Bouba" with the rounded and "Kiki" with the sharper figure, but to me this is just a relatively universal sense of continuity vs discontinuities:
the local curvature is continuous for "Bouba", every point on the curve has a single tangent, which evolves continuously as you walk along this presented curve.
For Kiki: the local curvature is discontinuous: at the inward or outward points, there are 2 tangents, so the tangent abruptly switches value when passing through this point when walking along the curve.
similarly the "B"s in "Bouba" are voiced plosives, while the "K"s in "Kiki" are unvoiced plosives.
I think people would similarily classify "Titi, Pipi, Touta, Poupa, Kouka" like "Kiki" but "Didi, Douda, Bibi, Gigi, Gouga" like "Bouba".
The vowels are obviously voiced by the vocal chord carrier wave "voice".
So when we pass through the unvoiced (T/P/K) plosives, we notice discontinuity like the discontinuously evolving tangents along the boundary curve of the figure.
Obviously mammals like dogs have a concept of continuity, topology, distance, they might get spooked by "open" stairs, because they can see between the planks, etc.
And when we hear voiced (D,B,G) plosives, the voice while muted still evolves continuously.
- ofrzeta
Related :) https://en.wikipedia.org/wiki/City_(novel)
- tdb7893
Somewhat more surprising to me is there's already evidence for this in baby chickens so it appears to exist even across very different animals.
- barkut
My fellow Frenchmen, do we tell them about Booba and "kiki" ?
- leoc
Good boys! Good boys.