When Serena Williams or Rafael Nadal make a great save or win a tennis match their faces fill with joy and they excitedly pump their fists. When they miss a save or lose a match, their faces flood with disappointment and they angrily punch their fists.  It turns out that extreme excitement and extreme anger look very similar. We believe we distinguish these feelings by gazing at people’s faces, reading them for subtle changes in emotion. But researchers recently found that people more accurately understand mood when they examine body language.

“When people rate a whole image, it was clear to them—they saw winners and losers,” explains Hillel Aviezer, now an assistant professor of psychology at the Hebrew University of Jerusalem. “When you see the faces alone, it is really confusing.”

Aviezer—who was a postdoctoral student with Alexander Todorov, a professor of psychology at Princeton University and a coauthor of the paper—wanted to see how accurate people were at predicting emotions when they examined facial expressions and body language. Psychologists often ask subjects to describe what someone is feeling by looking at a series of pictures of actors mimicking emotions. But Aviezer wondered how participants would react to more realistic, less scripted visages.

The researchers asked 45 undergraduate students to join one of three groups. One group looked at complete images of tennis players, meaning the photos included faces and bodies, as the athletes reacted to either winning or losing. The second cohort looked only at the faces of tennis players as they triumphed or failed. And the third set examined only the bodies of the tennis players responding to wins or losses.

Students that looked at either the complete photo, including face and body, or just an image of the body more accurately predicted the tennis player’s feelings. Those who saw only the faces had a 50/50 chance of correctly predicting whether the person was happy or angry.

“Many of these findings are pretty surprising because they went against the standard textbook [answer],” says Aviezer.  

Even though it seems that body language leads to more accurate impressions of mood, the participants did not realize it. Fifty-three percent of the participants that ranked the entire image believed they understood the tennis player’s emotion because of her facial expressions.

 “More than half of the participants believe they are reading facial cues … this study gave different results.”

Aviezer also asked another group of participants to look at photos where the face showed one emotion, such as extreme happiness, but the body displayed another feeling, such as extreme anger. Then he asked the subjects to mimic the facial expressions, generally a simple lab activity. If the face looked happy, but the body language projected anger, the students made angry faces, not happy faces.

“They changed their faces based on the bodies. We thought they would be good at imitating a posed face,” Aviezer says.

Overall, the report finds that body language plays a much larger role in understanding emotions. 

“We think the face is very important. [But] we don’t give the body much credit with how much information [it shares].”

The report appeared in the journal Science. 

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Timothy Clary / AFP/ Getty Images

U.S. swimmer Garrett Weber-Gale (L), shown with Michael Phelps, demonstrates the universal and time honored signal for victory at the Beijing Olympic Games on August 11, 2008.

Flat screens, phones and laptops soon will blaze with a body-language blitz: sweaty palms clasping mouths in disbelief, muscled arms folded in disagreement and – the sweetest Olympic pose – two fists hoisted aloft in displays of golden bliss.

“That position – the arms raised high – evokes triumph and it’s very ancient,” says Margaret J. King, director of the Center for Cultural Studies & Analysis in Philadelphia.

That traditional victory stance, rooted in the older, limbic portion of our brains where base emotions are fueled, may have been flashed when the earliest humans celebrated their first conquests, King suggests. Simply put, it pretty much predates Rocky,  "The Breakfast Club" and Notre Dame's "Touchdown Jesus." 

“I’m a cultural analyst but I use anthropology and I would bet that comes from a good hunt, from having successfully hunted and killed prey,” King said. “The Plains Indians’ dances used this as well, where the arms were over the heads, and that’s really, really important for group morale: ‘We won!’ ”

Scholars speculate that Neanderthals some 30,000 years ago had neck structures that gave them the ability to produce sounds similar to modern humans. If that’s so, why is body language still such a rich and vital part of our communication? Why didn’t evolution long ago wean away our need to silently reveal our inner feelings through postures and gestures?

“We still use body language because that’s the way our brains worked (eons) years ago when we first became human,” King said. “That brain is still ticking away; all research based on evolutionary psychology demonstrates that we are living in the 21st century with that same ancestral brain. This is what is called hard wiring. We still have the same bodily workshop. We just do different stuff in that workshop.”

“Body language is not an either-or situation,” adds Dennis Kravetz, a Scottsdale-Ariz.-based psychologist who specializes in male-female communication and body language. “If speech is more sophisticated than body language, then why haven’t chimps, dogs, and other animals developed speech as part of their evolutionary history? Rather, body language enhances communication.”

Evolution may have stripped away many outmoded human parts and proclivities that we no longer need but body language remains an essential tool in our modern communication kit, both Kravetz and King contend.

“We send out signals because that's the way it has worked for millennia: anything human beings have been doing for that long is not likely to change anytime soon,” King said. “It’s the language of sociability: You can tell if someone likes you. Can we work together? Can I trust you?

“We’re looking at body signals all the time to tell, first of all, if people are safe or unsafe. That’s one of the first things we look for in business is trust - is this a safe person to deal with?”

Likewise, if someone is marrying into a family, that person’s initial body language is carefully scanned by the family, she added, as they “look for the signals that say this is a consistent person, or that his words and language are not matching his body language, meaning he is not a person you can trust.”

Fair enough, but according to Charles Darwin’s theory of natural selection, certain traits are passed from generation to generation that allow human offspring to be better suited to survive this world. How does unintentionally broadcasting your anger, sadness or frustration through “negative body language” help you – or your great-great grandchildren – endure? Why hasn’t evolution sapped those awkward poses (hands on hips, crossed arms) from our nonverbal playbook?

While those signals subliminally convey bad feelings, they also alert others around us – hopefully friends or colleagues – that the person fidgeting, fumbling or looking forlorn may be in some emotional trouble. These unintended expressions are, in a sense, silent 911 calls.

“Communicating anxiety or sadness is not bad at all,” said Kravetz, author of "Relating Effectively.” "These are just as important … as feeling happy, excited and other positive states of mind. Body language helps us more fully communicate with another humans irrespective of what we are (saying).”

And in the workplace, if such “negative” body language is expressed among close company allies, “the sense of the group is: this guy is frustrated; something is off base here,” King said. “It’s a signal that the group needs to address this issue together – that we need to do something

“We have to work in teams. Human life is highly social and highly territorial. It explains a lot of our behavior,” she added. But like our ancient ancestors, "body language helps us relate to other people.”

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Michael Probst / AP

No one wants to see their broker doing this.

We've seen the facepalm in the now all-too-familiar images of woeful stock brokers, hands on their faces as they receive news of the plummeting stock market. (There's even a Tumblr, The Brokers With Hands on Their Faces Blog, devoted to cataloging images of, well, brokers with hands on their faces.) We witnessed it when Secretary of State Hillary Rodham Clinton covered her mouth as she watched Navy Seals execute Osama bin Laden (although she blamed it on allergies) -- and we even see this gesture when beauty pageant contestants are crowned.

When humans are scared or shocked, we tend to put our hands over our mouths, hold our foreheads or place our hands over our cheeks. But why?

“It’s called the pacifier gesture,” says Janine Driver, president of the Body Language Institute in Washington, D.C. “It’s like a kid sucking his thumb. When our hands go up and touch our faces, it’s saying to ourselves ‘It’s OK, it’s safe.’ It’s like our mother giving us hug. It says we’ll get through this.”

Driver explains that when we witness a terrible accident, hear bad news or are in disbelief, putting our hands over our mouths is physically expressing that we can’t emotionally take anything else in.

But as common as it seems, body language researchers have found not everyone around the world covers their mouths when they are shocked, scared or surprised, and women tend do palm their faces more than men.

"The softer version of this is a man in the boardroom who puts his pointy finger over his lips and his hands on his chin,” says Driver, who became a body language expert while working as an investigator for the Bureau of Alcohol, Tobacco, Firearms and Explosives and is the author of the book "You Say More Than You Think."

Other gestures expressing fear or surprise include grabbing our wrists like Martha Stewart did each day as she went to trial or covering our top lip with an index finger and putting our hand over our chin.

But the body language gesture universally used around the world when we are scared is opening our mouths in an oval shape and raising our eyebrows, Driver says.

“This is in our DNA,” she says. “It doesn’t matter if you’re black, white or Hispanic, from Iraq, Zimbabwe or Chicago.”

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