Charles Darwin would have been proud.
When fifth-grader Adam Staley grabbed a mask depicting a wide, open mouth in a surprised "O," he did something Darwin could have predicted more than 100 years ago. Adam automatically opened his eyes wide, forming a mock shocked expression to match the surprised mouth on the mask.
In 1872, Darwin wrote "The Expressions of Emotion in Man and Animals," theorizing that facial expressions -- like sadness, anger, distrust and surprise -- are innate and universal.
At the time, it was a controversial notion, but researchers have since confirmed that some facial expressions are uniform throughout the world.
But kids like 10-year-old Adam, who were at a Maryland Science Center exhibit, didn't know they were playing out decades of research done on the face and expressions.
They were only doing what comes naturally.
The "About Faces" exhibit lets people experiment with computers, mirrors and masks to learn more about their faces. "It's been one of the most interactive and popular exhibits we have had in a long time," said Charlene Cross, a science center exhibits specialist.
"People love it because your face is so personal," she said.
"It helps people understand the emotions of the face and that emotions are not unique among a single culture, or learned. Emotions are universal. It breaks down a barrier by helping people understand there is that universal connection," said Ms. Cross.
Adam was at the exhibit with his classmates from the Forcey Christian School in Silver Spring this week.
"The science class is talking about bones and so decided to come see this exhibit," said Warner Camp, a parent who accompanied his daughter's class to the science center.
The exhibit, which travels around the country, consists of 17 displays including computers, video, mirrors, masks and graphic images. It is from the San Diego-based Reuben H. Fleet Science Center and was created by a team of scientists, artists and educators.
Some of the displays were irresistible to Adam and his friends, who seemed to love the fact that this was a hands-on exhibit. Particularly irresistible was the one that let them mix and blend their own features with the likes of talk-show host Oprah Winfrey, Frankenstein and actor Pat Morita among others.
"It makes you look different," said 11-year-old Sarah Camp as she blended her looks with Princess Di and Jane Fonda.
"You can look like a movie star," said 10-year-old Graham Claybrook as he mixed the noses and eyes of a few celebrities with his own.
(Testing out the features of Frankenstein and a green zombie were by far the most popular with this school field trip.)
Even Mr. Camp, Sarah's father, got into the act. "This is cool," he said watching the children as their faces turned unrecognizable.
Some displays dispelled a few myths the children had about their own faces. For instance, "Sym-ulations" disproved their assumption that the left and right sides of their faces were symmetrical.
Another display, "Recognition," tested their ability to recognize different facial expressions. The "Cheshire Cat" is an optical illusion exhibit that allowed one person to wipe out the face of someone sitting on the opposite side.
One computer let the children freeze-frame any facial expression they wanted -- usually the most contorted look they could come up with.
Although it was all fun for the children, faces continue to fascinate scientists, psychiatrists, artists and others. There are ongoing studies to determine why the mere forming of a particular expression produces changes in things such as the heart rate and nervous system.
Others are looking at the route of emotions through the brain by studying facial expressions.
And did you know that the left side of your face is usually more expressive than the right side? Scientists believe it could have something to do with the fact that muscles on each side of the face are controlled by the opposite side of the brain.
The children at the Maryland Science Center hadn't really considered the scientific signification of faces. "I just see it in the mirror," Adam says of his own. "I don't really think about it."
But after seeing the exhibit, he decided to reflect a bit more on his own smiling face. "I like the way it looks," he says. "It's cool!"
Where: Maryland Science Center, 601 Light St.
When: Until April 30
Cost: To enter the Maryland Science Center, $8.50 for adults, $5.50 for children 4-17. Children under 4 are free.