How the apes taught us to laugh 16m years ago
Human laughter can be traced back 16 million years to the last common ancestor of humans and great apes, according to new research.
Dr Marina Davila Ross, a primatologist of the psychology department at the University of Portsmouth, England, reconstructed the origins of human laughter by mapping the laughter sounds of great apes and humans on an evolutionary tree.
Dr Davila Ross took more than 800 acoustic recordings from 22 juvenile and infant apes and three human babies while their palms, feet, necks and armpits were being tickled. The study compared the laughter sounds of all four great ape species and acoustically analysed and compared them to human laughter.
Despite acoustic differences between ape and human laughter, the results proved laughter is not a uniquely human trait, according to Dr Davila Ross.
Important
She said: "Our results on laughter indicate it has a pre-human basis. It is likely that great apes use laughter sounds to interact in similar ways to humans.
"This is important for emotional research in humans and animals as well as for the management of primates in captivity and in the wild." She added that the study showed that laughter evolved gradually during the last 10 to 16 million years of primate evolutionary history.
But she said that human laughter was nonetheless clearly distinct from the laughter of great apes because evolutionary changes had been more rapid in the last five million years.
Dr Davila Ross said that an unexpected similarity had been found between humans and gorillas and bonobos.
She explained that these apes were able to make laughter sounds while breathing out for up to four times the length of their normal breathing cycle.
hnews@herald.ie
- Ben Mitchell
