As chimpanzees grow, so does yawn contagion

Oct 16, 2013
The ability to empathize may influence chimpanzees' susceptibility to contagious yawning. Credit: Elainie Madsen

As sanctuary-kept chimpanzees grow from infant to juvenile, they develop increased susceptibility to human yawn contagion, possibility due to their increasing ability to empathize, says a study published October 16, 2013, in the open-access journal PLOS ONE by Elainie Madsen and colleagues from Lund University.

Scientists examined the extent to which two factors affected chimpanzees' to : their age, and their emotional closeness to the person . Thirty-three orphaned chimpanzees, 12 infants 1 to 4 years old, and 21 juveniles 5 to 8 years old, were included in the trials. A trial sequence consisted of 7 five-minute sessions: a baseline session, followed by three experimental sessions, where the human repeatedly either yawned, gaped or nose-wiped, and three post-experimental sessions, where social interactions continued without the inclusion of the key behaviors. Each chimpanzee separately observed an unfamiliar human and a familiar human preforming the sequence.

Researchers found that yawning, but not nose-wiping, was contagious for juvenile chimpanzees, while infants found neither yawning nor nose-wiping contagious. Specifically, human yawning elicited 24 yawns from the juvenile and zero yawns from the . Chimpanzees appear to develop susceptibility to interspecies contagious yawning as they grow from infant to juvenile, possibly due to their developing ability to empathize with the person yawning. Emotional closeness with the yawning human did not affect contagion. Madsen added, "The results of the study reflect a general developmental pattern, shared by humans and other animals. Given that contagious yawning may be an empathetic response, the results can also be taken to mean that empathy develops slowly over the first years of a chimpanzee's life."

As chimpanzees grow, so does yawn contagion
Researchers found that yawning, but not nose-wiping, was contagious for juvenile chimpanzees, while infants found neither yawning nor nose-wiping contagious. Credit: PLoS ONE 8(10): e76266. doi:10.1371/journal.pone.0076266

Aside from humans, cross-species yawn contagion and a gradual development yawn contagion, has previously only been demonstrated in dogs.

This video is not supported by your browser at this time.
Human yawning elicited 24 yawns from the juvenile chimpanzees and zero yawns from the infants. Chimpanzees appear to develop susceptibility to interspecies contagious yawning as they grow from infant to juvenile, possibly due to their developing ability to empathize with the person yawning. Credit: PLoS ONE 8(10): e76266. doi:10.1371/journal.pone.0076266


Explore further: Danish museum discovers unique gift from Charles Darwin

More information: Madsen EA, Persson T, Sayehli S, Lenninger S, Sonesson G (2013) Chimpanzees Show a Developmental Increase in Susceptibility to Contagious Yawning: A Test of the Effect of Ontogeny and Emotional Closeness on Yawn Contagion. PLOS ONE 8(10): e76266. DOI: 10.1371/journal.pone.0076266

add to favorites email to friend print save as pdf

Related Stories

Puppies don't pick up on yawns

Oct 23, 2012

Do you get tired when others yawn? Does your dog get tired when you yawn? New research from Lund University establishes that dogs catch yawns from humans. But not if the dogs are too young. The study, published in Springer's ...

Why yawning is contagious in bonobos

Nov 14, 2012

Being socially close to another bonobo is more likely to make bonobo apes yawn in response to the other's yawns, according to research published November 14 in the open access journal PLOS ONE by Elisabetta Palagi ...

Fetuses yawn in the womb, according to new research

Nov 21, 2012

The 4D scans of 15 healthy fetuses, by Durham and Lancaster Universities, also suggest that yawning is a developmental process which could potentially give doctors another index of a fetus' health.

Recommended for you

Danish museum discovers unique gift from Charles Darwin

12 hours ago

The Natural History Museum of Denmark recently discovered a unique gift from one of the greatest-ever scientists. In 1854, Charles Darwin – father of the theory of evolution – sent a gift to his Danish ...

Top ten reptiles and amphibians benefitting from zoos

14 hours ago

A frog that does not croak, the largest living lizard, and a tortoise that can live up to 100 years are just some of the species staving off extinction thanks to the help of zoos, according to a new report.

User comments : 0