Friday, August 03, 2007
Adelie Penguin Diet Change
The NY Times today tells us of research on Adelie penguins in Antarctica by Dr. Steven Emslie of the University of North Carolina - Wilmington. For years Emslie has been studying Adelie penguin mummies (like the one pictured) that are preserved for tens of thousands of years in the cold dry climate of Antarctica.
Lately his research has turned to studying trends in their diet, based upon isotopic analysis of eggshell. According to the article, these studies show that about 200 years ago, Adelie diet switched from a focus on fish, to their current diet of krill and other organisms lower on the food chain. From the article:
"The timing of the shift corresponds to the rise of human hunting of fur seals in the Southern Ocean, followed later by whale hunting. Whales and seals are major consumers of krill, so some scientists have suggested that their depletion led to a surplus of the tiny crustaceans.
Dr. Emslie said his work appears to validate this hypothesis."
I'll be very interested to hear John Carlson's opinions on this.
Another full disclosure: Steve Emslie and I went to graduate school together at the University of Colorado. Steve started out in archaeology and worked for me at the excavation of 5MT(UMR)2785 near Mesa Verde in southwestern Colorado. From the beginning, Steve specialized in faunal analysis and he was always bringing stinky road-kill to the offices we shared for his comparative collection. After finishing his MA in Boulder, he became so interested in the biological aspects of faunal analysis that he switched fields and went on to get a PhD in biology from the University of Florida.
Steve has gone on to have a stellar career. His work with fossil California condors in the Grand Canyon area forms much of the scientific underpinning for the recent reintroduction of condors there. I also recently saw that work he has done with fossil remains from Sandia and Marmot Caves in New Mexico has documented California condor and passenger pigeon populations there in the Late Pleistocene.
My goodness, two old friends in the papers in two days!