Contagious yawning has been reported for humans, dogs and several non-human primate species, and associated with empathy in humans and other primates. Still, the function, development and underlying mechanisms of contagious yawning remain unclear. Humans and dogs show a developmental increase in susceptibility to yawn contagion, with children showing an increase around the age of four, when als...

Contagious yawning, the onset of a yawn triggered by seeing, hearing, reading, or thinking about another person yawn is a well-documented phenomenon. The mechanisms that drive contagious yawning are as yet unknown, but there is recent evidence of a link between contagious yawning and self-processing (S.M. Platek, S.R. Critton, T.E. Myers, G.G. Gallup Jr., Contagious yawning: the role of self-aw...

In all the species of nonhuman primates for which data on sex differences in the frequency of yawning are reported, males yawn much more than females (Bertrand 1969; Deputte 1978; Goy and Resko 1972; Hadidian 1980; HA and DeVore 1965; Redican 1975; Rinaldi 1985; Wolfheim and Rowell 1972). This différence has been related to sexual dimorphism in canine size: The larger size of male canines may m...

In humans, the susceptibility to yawn contagion has been theoretically and empirically related to our capacity for empathy. Because of its relevance to evolutionary biology, this phenomenon has been the focus of recent investigations in non-human species. In line with the empathic hypothesis, contagious yawning has been shown to correlate with the level of social attachment in several primate s...

In humans and apes, yawn contagion echoes emotional contagion, the basal layer of empathy. Hence, yawn contagion is a unique tool to compare empathy across species. If humans are the most empathic animal species, they should show the highest empathic response also at the level of emotional contagion. We gathered data on yawn contagion in humans (Homo sapiens) and bonobos (Pan paniscus) by apply...

The proposed system aims to enhance transportation safety by reducing the number of accidents caused driver fatigue and drowsiness, which have become increasingly common. analyzes facial bodily gestures such as eye tiredness yawning identify signs drowsiness fatigue. Eye aspect ratio (EAR) is used detect measuring distances between horizontal vertical landmarks. Yawn detection performed calcula...

Six adult female chimpanzees were shown video scenes of chimpanzees repeatedly yawning or of chimpanzees showing open-mouth facial expressions that were not yawns. Two out of the six females showed significantly higher frequencies of yawning in response to yawn videos; no chimpanzees showed the inverse. Three infant chimpanzees that accompanied their mothers did not yawn at all. These data are ...