Newslink : 500-year-old clams unlock history of Earth's oceans

Clams are more than just a tasty dish in chowder, they're also important in understanding Earth's history.The world's oldest animals, 500-year-old clams have given scientists an unprecedented look at the climate history of the oceans. 

By studying growth rings in the shells of quahog clams, scientists have pieced together the history of the North Atlantic Ocean over the past 1,000 years. The method is similar to how tree rings can serve as climate proxies by revealing clues about past weather and climate changes, including droughts..... [Read it]