New research out of Texas says that the endangered blue whale species could be saved by its earwax. Blue whales build up layers upon layers of earwax throughout their lives that form a plug up to a foot long that sticks there until they die. Gross I know but it’s for the best. Kind of how it works with tree-ring dating, scientists can look at this plug and find the whale’s age, changes in hormones, and what chemicals they are exposed to in the ocean—providing information about the human impact on these creatures, and what’s killing them off. At one time blue whales were found in every ocean, they are now down to 8,000 thanks to overhunting.