Great apes may have been laughing with a similar rhythm to modern humans for at least 15 million years, a University of Warwick study reveals. The finding offers unexpected clues to how human speech evolved.

A study of 140 laughter sequences found the same rhythmic timing pattern in humans, chimps, gorillas, bonobos and orangutans.

A new study suggests humans and great apes have been giggling in similar ways dating back 15 million years.