During a campaign led by the University of Exeter, scientists discovered a 500-year-old clam of the species Arctica islandica, also known as the Ocean quahog, in the depths of the North Atlantic. This discovery positions the clam as one of the oldest marine organisms ever studied, offering unique data about environmental changes that have occurred over centuries. Remarkably, the clam was born in the early 16th century, prior to modern instruments that measure ocean temperature or chemical composition.

The clam's shell grows in annual layers, akin to the rings of a tree, which allows for a natural record of its surrounding environment at the time each layer formed. Each layer serves as an archive of information including variations in ocean temperature and salinity, as well as other environmental factors. By analyzing these layers, scientists can reconstruct historical data regarding ocean conditions, enabling better understanding of climate change impacts on marine ecosystems over time.

This finding holds significant implications for the study of marine biology and climate science, as it provides a living window into conditions that existed long before contemporary data collection. Such information is vital for informing current environmental policies and understanding long-term ecological trends in an era increasingly impacted by climate change.