Throughout their lives, baleen whales develop wax in their ears, just like humans do. Every six months, a new layer, or “lamina,” is deposited. The laminae have regular color differences due to annual feeding and migration patterns, allowing researchers to distinguish each and every six-month period in the whales’ lives. Since whales don’t clean their ears like we do, their entire history is recorded in the wax plug by the time they die. These earplugs have long been used by scientists to figure out the age of whales, but it turns out the wax can tell us much more about whales’ lives than just how old they are.
via Ars Technica
Image: NOAA
