- Science
- BBC World, @bbc_ciencia
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We’ve all done it. We have all seen it. She is the «face of anger», of anger, fury, rage, or whatever you want to call it. And now scientists say that it seems to be part of our basic biology as human beings rather than a cultural reaction.
Researchers at the University of California at Santa Barbara (known as UCSB or UC Santa Barbara) and Griffith University in Australia identified «functional advantages that led to the evolution of the specific appearance of the anger face,» explained the center of American studies on his website.
«The expression is in every culture, and even children with congenital blindness make the same face without ever having seen one,» explains lead study author Aaron Sell, a professor at Griffith University’s School of Criminology and a former investigator for the UCSB Center for Developmental Psychology.
And the face of anger is more than a display of anger, but has evolved to perform the signals of strength of the human being.
show of force
Animals normally use their morphology during a conflict to increase the evaluation of the rivals’ fighting ability.
And now, say the scientists of the study, published in the scientific journal Evolution and Human Behavior«Recent research has shown that humans assess the fighting ability of others by monitoring signals of force, and that the face contains such signals.»
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«The expression is in all cultures, and even congenitally blind children make the same face without ever having seen one,» says the study’s author.
The researchers suggested that the muscle movements that make up the facial expression of anger were «selected because they increased others’ assessments of the individual’s strength,» which they say «increases bargaining power» between two people.
This analysis goes against the traditional theory that the angry face is an arbitrary set of features that evolved to signal aggressive intent.
To compare both theories, the researchers manipulated one by one, and in the absence of the others, the key muscles that make up the angry face.
The most common trait is a frown, and they also include widening of the nostrils, raised cheekbones, lips drawn in and out, mouth upturned, and chin pushed up and out.
bargaining power
The researchers consider that, taking into account that the face of anger increases bargaining power, the human being needs to communicate his state to avoid a conflict and, therefore, they say, it is necessary to express it facially.
«The angry face not only signals the start of a conflict. Any facial distinction could indicate it. Our hypothesis is that the angry face evolved in a specific way because it accomplishes something more for the person expressing it,» explains Sell.
«Each element,» he adds, «is designed to help intimidate others, making the angry individual appear more capable of harm if not appeased.»
One of the hypotheses from which the researchers started is that an angry face makes a person look stronger.
Using computer-generated faces, each individual component that makes up the angry face was shown to make those computer-generated people appear stronger.
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«No feature of the angry face appears to be arbitrary; they all deliver the same message,» says one of the researchers.
One of the most common features is a frown. The researchers airbrushed an image to place her eyebrows either low or raised.
«With this difference alone, neither face appeared ‘angry.’ But when these two faces were visible to the subjects, they said the face with the lowered eyebrows appeared to belong to a physically stronger man,» Sell says.
The experiment, UCSB explains, was repeated with the other features of the angry face.
«Our previous research showed that humans are exceptionally good at assessing fighting ability just by looking at someone’s face,» explains the study’s lead author.
«Given that people who are judged stronger tend to get away with murder more often, other things being equal, the researchers concluded that the explanation for the evolution of human rage face shape is surprisingly simple: it’s about a display of a threat,» he adds.
John Toody, one of the study’s co-authors, a professor of anthropology at UCSB and co-director of the university’s Center for Evolutionary Psychology, explains that this helps to understand why evolution caused the face to develop that way in moments of anger. so that it appeared at the same time as the onset of anger.
«The anger – he adds – is triggered by the refusal to accept the situation, and the face immediately organizes itself to announce to the other party the costs of not making the situation more acceptable».
And what is «most gratifying about these results,» he concludes, is that «no feature of the angry face appears to be arbitrary; they all deliver the same message.»