Scientists have found the record of a whale’s life in, of all places, its ear.  The carcass of a blue whale, which died after being struck by a ship, has yielded a 10″ slab of ear wax which researchers have found to reveal not only the age of the whale, but  also its stress level, and the pollutants in the water in which the whale was swimming.

This Dead Whale Is Helping Science in an Incredibly Gross Way

Two of the handlers of the sacred plug were Stephen Trumble and Sascha Usenko, professors at Baylor University in Waco, Texas. Knowing that past researchers have probed whale blubber to suss out what chemicals the creatures were exposed to, they decided to do the same with their earplug. So they barraged it with various laboratory tests to build a timeline of their luckless whale’s life, as defined by what hormones it secreted and what poisons it encountered in the seas. Their results, recently published in the Proceedings of the National Academy of Sciences, showed that the animal had a colorful chemical history, one that was not exactly pleasant.

By the time it reached maturity, the whale had already sweated out buckets of cortisol, a hormone associated with stress. That might be due to environmental pollution or competition with other breeding whales. The researchers also found pesticides, PCBs, mercury, and flame retardants. All these things washed over the whale’s body and were lodged in its wax, although their effects on its overall health remain a matter of speculation. 

Usenko and Trumble say this is the first time in history someone’s gleaned a whale’s life story this way. “There is nothing like it. It really should be classified as a new field of research,” Usenko said. They hope in the future this method can be used on other plugs kept in storage around the world, so that science can understand more about how whales are affected by our pollution, fishing nets, and sonar and thudding engine noise, as well as anthropogenic climate change. (The whale that provided Baylor’s earwax would probably add “ship collisions” to the list, if it could.)

Thanks to Phil Leon for contributing to this post.