Scientists trace laughter back 15 million years through ape vocalizations

Fifteen million years before the first human word was spoken, something like laughter was already moving through the trees. Researchers who tickled gorillas and recorded the results have found that the rhythmic, breath-driven bursts we recognize as laughter are not a human invention but an ancient primate inheritance — a vocalization shared across species whose common ancestor predates our own genus by an enormous span of time. The discovery quietly repositions humanity not as the originator of complex communication, but as one more branch on a very old, very social tree.