close up of a young yellow chicken on a farm

‘Mind-Blowing’ Baby Chick Study Challenges a Theory of How Humans Evolved Language

February 19, 2026 | Source: Scientific American | by Cody Cottier

Why does “bouba” sound round and “kiki” sound spiky? This intuition that ties certain sounds to shapes is oddly reliable all over the world, and for at least a century, scientists have considered it a clue to the origin of language, theorizing that maybe our ancestors built their first words upon these instinctive associations between sound and meaning. But now a new study adds an unexpected twist: baby chickens make these same sound-shape connections, suggesting that the link to human language may not be so unique.

The results, published today in Science, challenge a long-standing theory about the so-called bouba-kiki effect: that it might explain how humans first tethered meaning to sound to create language. Perhaps, the thinking goes, people just naturally agree on certain associations between shapes and sounds because of some innate feature of our brain or our world. But if the barnyard hen also agrees with such associations, you might wonder if we’ve been pecking at the wrong linguistic seed.