Chomp a cup for science

Chomp a cup for science

When you walk into a bar you expect to see whiskey bottles and beer taps, not stacks of tooth-imprinted foam cups.

Yet at the Fermilab Users' Center, the cups hold a place of honor behind the bar. They serve as a conversation piece and as evidence of the varied ethnic backgrounds of people who come to the Illinois lab from dozens of nations.

“One time we were at the bar, solving the problems of the world, and the conversation came up who was Native American and who wasn't,” said Ernie Villegas, a mechanical engineer at Fermilab.

True to their scientific roots, the group put the question to a test: They asked people to bite the foam lips of disposable cups.

The results reveal a pattern dubbed “shovel tooth” or “spade tooth,” in which the backs of the incisors have a cupped, shovel shape and leave a U-shaped mark.

This pattern, called Sinodonty, appears only in those with northern Asian or Native American ancestry. It was first described by anthropologist Christy Turner of Arizona State University. He said the distribution of the trait suggests that people from northern China migrated to Mongolia and then across the Bering Strait to North America about 14,000 years ago.

Fermilab's René Padilla was surprised when the trait showed up in his family. Some theorize that Native Americans carried the trait to Latin America; Padilla assumes this is how his Puerto Rican ancestors picked it up.

At last count, people at Fermilab had collected 16 bite patterns showing the trait. They would love to find more samples, especially from other laboratories.

“You would be surprised. A lot of people that you wouldn't think have it, will. There are so many mixtures of blood that people don't really know what they are,” says Villegas, who is half Apache. He brought the cup test to Fermilab two years ago after learning about shovel tooth on a vacation to the Dakotas.

“I wouldn't say that it's a study, really,” he says, “but it's an interesting thing to do.”

Tona Kunz