from the Ehh,-What's-Up-Doc? dept.
Scientists can peer at least nine months into a Tasmanian devil's past by studying its whiskers, a new study led by UNSW Sydney has found.
The long, wiry whiskers on these stocky marsupials hold chemical imprints from food they've eaten in the past – records that can help tell broader stories about their foraging habits, habitat use and how they respond to environmental change.
Researchers have now mapped this timescale for the first time, showing that devils' whiskers can capture seasonal dietary changes over at least nine months and potentially up to a year.
[...] Up until now, tracing a devil's culinary history with its whiskers has been a bit like using an out-of-order time machine: scientists could see the chemical records, but couldn't confirm if they were from a week, month, or year ago.
To get a clearer picture of the timeline, the UNSW-led research team fed tablets enriched in heavy stable isotopes – types of atoms that don't decay into other elements over time – to six captive devils at three-month intervals. These stable isotopes acted as timestamps, marking the whiskers with each season's passing.
When more than a year had passed, the team removed the longest whisker from each animal for analysis. They found the whiskers grew fast at first before slowing down, and that whiskers on different parts of their muzzle grew to different maximum lengths. On average, the longest whiskers held at least nine months of the animal's ecological history – but as whisker growth slows over time, the researchers suggest it's likely they can hold up to a year.
Marie R. G. Attard, Anna Lewis, Stephen Wroe, et al. Whisker growth in Tasmanian devils (Sarcophilus harrisii) and applications for stable isotope studies [open], Ecosphere (DOI: 10.1002/ecs2.3846)