A new study shows that yawning is contagious among budgerigars (Melopsittacus undulatus), a social, flock-living parrot also known as budgies or parakeets. When one budgie yawns, another is sure to follow, according to the research published recently in Behavioural Processes.
Up until now, contagious yawning has been documented only in people and a few non-human primates. The researchers define contagion as the matching of reflexive or involuntary behaviors, of which yawning provides a classic example.
The findings are significant because it can help researchers understand the function of such behavior, according to Andrew Gallup, Ph.D., who worked on the study as a graduate student at Binghamton University. Gallup is now a postdoctoral research associate at Princeton University’s Department of Ecology and Evolutionary Biology.
“Comparative research on contagious yawning is important for understanding its potential function, and whether this behavior is involved in higher level cognitive processing,” Gallup said. “For instance, a recent investigation of contagious yawning concluded that the red-footed tortoise does not yawn in response to observing another tortoise yawn. The authors therefore suggest that contagious yawning is not simply the result of a fixed action pattern but may involve more complex social processes.”
Although more research needs to be conducted, contagious yawning may ultimately coordinate mental state and a group’s collective movements, according to the study. Spontaneous yawning, on the other hand, is associated with stress, arousal and thermoregulation. Spontaneous yawning has been observed in a variety of species, including budgies.
“Members of the team had been performing research on budgerigars for years, and there was an interest in whether these highly social birds displayed contagious behaviors like yawning,” Gallup said. “If contagious behaviors serve important functions, like group coordination, in social mammals, it seemed reasonable that yawning may be contagious in social, non-mammalian species as well. Similar to rodents, these birds also yawn more frequently than humans and some non-human primates, making this behavior [easier] to study in a naturalistic context.”
The researchers video recorded an undisturbed, established flock of budgies housed at Binghamton University between April 2008 and October 2009. The flock contained 21 birds (nine males, 12 females), all non-breeding, between 11 and 15 years of age. Three birds died of natural causes during the study period.
Taping sessions took place within the flock’s indoor aviary on a total of 15 days during the study period. Each taping session lasted 90 minutes and started at one of three times: early morning, afternoon or early evening. A total of 23 sessions were recorded.
Yawning was defined as a wide opening of the beak and slight closing of the eyes, followed by a brief pause with stretching of the neck.
Despite the low frequency of yawning (1.28 to 2.96 yawns per bird per hour, depending on the time of day), a bird was more likely to yawn within 40 seconds or less of another bird’s yawn, according to the study.
In addition, the study revealed that there were a “substantial number of yawns separated by at least 300 seconds from the previous yawn, but few spaced at intermediate intervals. Taken together, the inter-yawn spacing distribution suggests that yawns were social influenced (i.e. contagious). In other words, long periods of no yawns were broken by a budgerigar’s yawn that was then followed by a cascade of yawns among the others.”
Gallup said it’s possible that other highly social and large-brained birds, such as corvids, may experience contagious yawning. However, he doesn’t have any immediate plans to investigate contagious yawning in other animals.
The next step is to demonstrate contagious yawning between budgies in an experimental setting, he said.
“The current research was entirely observational, and thus it is important that we follow up with an experimental demonstration of this finding,” Gallup said. “In other words, we need to show that yawns are truly socially-contagious rather than just temporally clustered for other reasons.
“Our previous research explored the contagious nature of yawning and stretching in budgerigars through video stimuli, but there were limitations to this approach. In particular, the quality of the stimulus is questionable since it was recorded from freely behaving birds, and the degree to which the experimental birds were attending to the video screen is an issue. Therefore, in this study we tried to lay a stronger foundation for future experimental work by taking a naturalistic approach. While experimental studies are needed to confirm and clarify the degree and precision of contagion, we propose that experiments be designed using live birds as the target stimulus.”
And for those budgie-owning readers who may now try yawning in front of the bird in hopes of trying to trigger a yawn: Don’t expect much, according to Gallup.
“We do not have any evidence to suggest that budgies will yawn in response to human yawns,” he said. Although he notes that they did not explicitly investigate this possibility.