Human-Ape Links Heard in Laughter

Human laughter is rooted in the emotional displays of the common ancestor we share with apes, suggests an analysis of the vocalizations of tickled juvenile apes and humans.

A team led by psychologist Marina Davila Ross of the University of Portsmouth, UK, undertook the task of tickling 25 young apes and humans, and recorded the resulting laughter (see video). They report this week in Current Biology that similarities between the acoustic characteristics of each species' laughter roughly reflects their genetic relatedness1.

"Particularly the gorilla and the bonobo could produce [human-like] sounds while breathing out for more than 10 seconds," says Davila Ross. The more distantly related orangutan and siamang's laughter, meanwhile, was correspondingly distinct.