Author: Robby Berman / Source: Big Think

- It’s just been discovered that whale earwax contains a record of a whale’s sub-lethal stressors.
- It’s generally agreed that cortisol is a reliable indicator of a mammal’s response to stress.
- We now have a detailed 146-year impact study of human activity on whales.
Baleen whales (Mysticeti) have been subjected to human interference for a long time. The 14-member set, which includes humpbacks, minke whales and blue whales, has dealt with being hunted, increased boat traffic and fishing, noise, and pollution. It’s been difficult to ascertain the effect all this has had on individual whales, though, due to the challenges involved in collecting hormones and tracking changes over single whale’s lifetime. Baleens themselves can provide some information, but just for the last decade. However, a remarkable long-term record of a whale’s stress history has been discovered: the whale’s earwax plug.
According to comparative physiologist Stephen Trumble of Baylor University and his team of researchers, each plug contains a history of a whale’s sub-lethal stressors. Their study, just published in Nature Communications, reveals for the first time what our activities for the last 146 years have been like for leviathans.
Gross, maybe. Incredible, for sure.
(Trumble, et al)
Black horizontal marks show six-month intervals
The baleen-whale earwax plug is large: up to a foot and a half long and two pounds in weight. Every six months — as…
The post Whale earwax reveals 146 years of humanity’s impact appeared first on FeedBox.