The male blue whale whose earplug was harvested for the study. (Photo : Michelle Berman-Kowalewskic, Ph.D., Santa Barbara Museum of Natural History, Santa Barbara, Calif.)
It might not be pretty, but it turns out that a blue whale's earwax can reveal a plethora of information about the whale's history, as well as more insight into the pollutants that pervade our oceans, according to a new study in the Proceedings of the National Academy of Sciences.
"The type of information we can derive from these earplugs along with our methodology is exceptionally valuable. There is nothing like it. It really should be classified as a new field of research," said Sascha Usenko, an assistant professor of environmental science in Baylor's College of Arts and Sciences.
Scientists led by researchers from Baylor University were able to reconstruct valuable information about a blue whale's personal history by studying the different layers of wax that had built up in the whale's ears. Whales, lacking an effective apparatus to clean out their ears, end up with deposits of earwax that can date back to their earliest days. Experts can analyze the levels of hormones, such as the stress-related cortisol, allowing them to get a clearer picture of the whale's emotional and physical journey.
In addition to the biological data about the whale, the team also realized that the earwax contained some key insights into environmental issues such as manmade pollutants in our oceans.
"Scientists in the past have used this waxy matrix as an aging tool, similar to counting tree rings. Then, the question arose: Could whale earwax chronologically archive chemicals, such as man-made pollutants?" Usenko said.
Whale blubber has been used in the past to derive chemical exposure, but the new earwax method allows scientists to look further into the past, since it accumulates without much deterioration. In the study, the researchers came across pesticides, flame retardents, mercury, and more, highlighting the impact that manmade chemicals have on the environment, even after we've stopped using them.
You can read the full published study in the Proceedings of the National Academy of Sciences.