In this July 2007 file photo a young lobster is seen on Friendship Long Island, Maine. Scientists have now figured out where the growth rings are to determine the age of a lobster. Researchers found that growth rings found in the eyestalk - a stalk with an eyeball on the end connected to the body of lobsters, crabs and shrimp. In lobsters and crabs, the rings are also found in teeth-like structures in their stomachs used to grind up food. (AP Photo/Robert F. Bukaty, File)

Scientists have finally figured out how to determine the age of a lobster.

Raouf Kilada (row-OOF' kuh-LAH'-duh) of the University of New Brunswick presented his research Thursday at a lobster science conference in Portland, Maine.

Scientists already knew how to tell a fish's age by counting the growth rings found in its and a or clam's age from the rings of its shell.

But nobody knows how old lobsters can live to be. Some people estimate they live to over 100. Before now it was thought that when lobsters, shrimp and molt, they shed all parts of their bodies that might record annual growth bands.

Kilada and other researchers found that growth rings are found in a lobster's eyestalk and in teeth-like structures in their stomachs used to grind up food.