Summary:Chimpanzees have been observed yawning and lying down when a humanoid android mimics the facial expression of a yawn, suggesting contagious yawning by an artificial agent. This study is the first to demonstrate contagious yawning in response to an inanimate model, suggesting that yawning, in addition to being a social reflex, may also be a calming signal.
The most intense yawning response occurred when the robot’s mouth was fully open, with no response to expressions of surprise or neutrality. These findings open new possibilities for understanding nonverbal communication and the evolution of empathy between species.
Important facts:
- First dead trigger: Chimpanzees have shown that yawning is contagious in humanoid androids: an unprecedented discovery.
- Authentic answer: The yawning response depended on how far the robot’s mouth was open, suggesting perceptual sensitivity.
- Rest signal behavior: The chimpanzees also made the bed together and only lay down when yawning, suggesting a strong behavioral bond.
Source: St. George’s University of London
Chimpanzees (Pan troglodytes) can produce android yawns that mimic human facial expressions, according to new research from City St. George’s, University of London.
The study, published in Scientific Reports, shows that chimpanzees yawn and lie down in response to an android yawning. This suggests that it may be a signal to relax rather than simply triggering an automatic response.
According to the authors, the results demonstrate for the first time that yawning is contagious through an inanimate model. The study also sheds light on the role of social factors in shaping yawning disease.
Contagious yawning (where observing another animal yawning elicits a similar response in an individual) is primarily seen in mammals and some fish. Although the evolutionary origins of yawning and its contagiousness are still unknown, some animals, including humans, can be infected by the yawning of other species.
To test the chimpanzees’ responses, Dr Ramiro Joly-Mascheroni, Honorary Research Fellow at City Saint George’s, Professor Beatriz Calvo-Merino, Professor Tina Forster (Professor of Cognitive Neuroscience at City Saint George’s) and colleagues from the University of Girona used the Android cap on 14 adult chimpanzees, aged between 10 and 33, at the Fundació Mona Primate Sanctuary in Spain.
The android’s head made facial expressions—yawn, open yawn, and neutral—and each facial movement lasted for 10 seconds. The chimpanzees displayed a contagious yawn in response to the android’s yawn.
The adult chimpanzees gradually responded to the android’s different facial expressions. The greatest yawning morbidity occurred when the android’s mouth was fully open (yawning), when its mouth was partially open (yawning), and when the android had its mouth closed, there was no contagious disease. Only during yawning did they collect the bed before lying down.
Lead author Dr. Joly-Masheroni said: “Our results show that chimpanzees exhibit a contagious form of yawning when exposed to an inanimate, non-biological organism, a humanoid android, that appears to be yawning.
“Despite its ridiculously basic functions (we still don’t know exactly why we yawn, why yawning is contagious), yawning may still have an evolutionarily ancient nonverbal communication role, and its contagious aspect could help us discover more about how humans and animals developed forms of communication and social interaction.”
Professor Calvo-Merino said: By examining primate yawning responses to artificial agents, we can understand mechanisms of social cognition and interactions beyond humans. This interdisciplinary research fosters collaborations between fields such as psychology, robotics, and zoology.
Researchers say that further research is needed into the mechanisms behind this response to determine whether other actions performed by robots or artificial beings are contagious to animals and to what extent this response resembles that of humans.
About this social contagion research news
Author: George Wigmore
Source: St. George’s University of London
Contact: George Wigmore – St. George’s University of London
Image: The image is credited to StackZone Neuro
Original Research: Open access.
“Chimpanzees yawn when observing an android yawn” by Ramiro Joly-Mascheroni et al. Scientific Reports
Abstract
Chimpanzees yawn when they see an android yawn.
This study examines contagious yawning in adult chimpanzees (Pan troglodytes) in the presence of a non-biological humanoid, an android. The chimpanzees observed an android displaying specific facial expressions, including yawning and wide-eyed gazes.
The results showed that adult chimpanzees displayed yawning disease among agents, with a graded response: the highest contagiousness occurred when the android’s mouth was fully open (yawning condition), the lowest response occurred when the mouth was partially open (open-mouth condition), and there was no contagiousness when the android’s mouth was closed (closed condition).
In addition, the chimpanzees exhibited sleep-related behaviors, such as gathering sleeping materials, nesting, and lying down, while they observed the android yawning.
This suggests that the yawning of an unknown model may serve as a contextual cue for comfort, rather than triggering a motor resonance response.
These results contribute to understanding the susceptibility of nonhuman primates to infection-induced behavior, particularly yawning, even when stimulated by an artificial factor.
This study sheds light on the role of social factors in the development of contagious yawning and calls for further research on interspecies and intraagent interactions.
