The effects of the melting polar ice caps may one day be felt well beyond the poles, though. As the polar ice caps shrink, sea levels begin to rise, creating serious problems for coastal areas around the globe. Fortunately, we can do our part to slow down and prevent the environmental changes causing the polar ice caps to melt.
Paabo and colleagues used a new method for sequencing ancient, degraded genetic material to put together the 400,000-year-old specimen's mitochondrial genome. It is the oldest DNA ever found outside permafrost conditions -- in other words, it was not permanently frozen.
The oldest human remains were discovered in Ethiopia by a team of archeologists in 1967, and were originally estimated to be only about 130,000 years old. In 2005, more sophisticated dating techniques put the human skulls at about 200,000 years, confirming that they are the oldest known human fossils.