One of the more difficult problems associated with climate change is trying to predict what will happen to animal species when temperatures increase. It is expected that there will be winners and losers. As with so many environmental issues, however, predictions about which species will prevail and which will struggle are useful almost more to humans than to the species themselves. Disruptions of ecosystems can cause enormous headaches for humans - think of zebra mussel infestations, suburban deer invasions, fire ant population increases. So although Antarctica is rather remote, a recent study examining the response of elephant seals to the a previous warming period in earth's history provides some interesting background for scientists to use in predicting how other species might fare in a warmer world. Thanks to the generous folks over at PLoS Genetics, you can read the entire article online if you choose.
The main findings of the study, which examined DNA from old elephant seal carcasses found on the Victoria Land Coast (VLC) in the Ross Sea (hooray for Antarctic weather and its remarkable preservation qualities), were that when the VLC became ice-free about 8,000 years ago, elephant seals quickly moved to the area from Macquarie Island. When the ice returned, some went back, but all departed from the Ross Sea. The researchers examined changes in mitochondrial DNA to determine changes in population diversity. Genetic diversity expanded quickly (within a few generations) after the a colony was established on the VLC. The implications for this are that species that are highly mobile, as elephant seals are, can respond quickly to changing habitat situations. Other species that are less mobile will probably not fare as well in the face of climate change. Their findings will be useful for researchers who try to predict how various species will react to climate change, and use those findings to develop conservation plans.
Also, it's pretty frickin' cool that they got so much usable DNA from 8,000 year old elephant seal remains.