Thu March 20, 2014
Dr. Stephen Trumble, Baylor University - Analysis of the ear wax of whales
We can learn a great deal from the analysis of the ear wax of whales.
In today’s Academic Minute, Dr. Stephen Trumble, associate professor of biology at Baylor University, explains how a whale’s ear wax can help us find definitive answers to a wide array of questions.
Dr. Stephen Trumble is an associate professor of biology at Baylor University. His research primarily focuses on the physiological adaptations and mechanism of animals in extreme and changing environmental conditions. In 2003, he earned a PhD in marine biology from the University of Alaska Fairbanks
Dr. Stephen Trumble - What Can We Learn From the Ear Wax of a Whale
Scientists in the past have used whale earwax as an aging tool, similar to counting tree rings. Dr. Sascha Usenko and I questioned whether whale earwax could chronologically archive chemicals, such as man-made pollutants or hormones. We developed analytical methods capable of answering that very question.
Using a blue whale's earplug, we were able to extract and analyze the stress hormone cortisol, male sex hormone testosterone, organic contaminants such as pesticides and flame retardants, and mercury, demonstrating that both man-made and endogenous chemicals are recorded and archived in whale earwax.
We have been able to reconstruct contaminant and hormone profiles using whale earplugs, determining—for the first time—lifetime chemical exposures and hormone profiles—from birth to death—for an individual whale; information that was previously unattainable.
Historically, scientists have used whale blubber to determine hormone and chemical exposure, but that method only provides information over short, temporal scales; not to mention these samples can be logistically difficult to obtain and cost-prohibitive. With these new data derived from whale earwax, we able to assess the human impact on individual whales and multiple generations, as well as marine ecosystems.
You have this seemingly unattainable question: How are humans impacting these animals over their lifespan? There is ship traffic, environmental noise, climate change and contaminants. Now, we are able to provide definitive answers by analyzing whale earwax plugs.
Using whale earplugs we are able to go back in time and analyze archived museum earplug samples that were harvested in the 1950s and examine critical issues such as the effects of pollution, use of sonar in the oceans and the introduction of specific chemicals and pesticides in the environment over long periods of time.