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.
Scientists working in Ethiopia say they've found the earliest known fossil on the ancestral line that led to humans. It's part of a lower jaw with several teeth, and it's about 2.8 million years old. Anthropologists say the fossil fills an important gap in the record of human evolution. Although it's risky to say you've got the first or oldest of anything, Brian Villmoare, a paleoanthropologist at the University of Nevada, Las Vegas, is sure he and his team have the earliest specimen of Homo, the human genus.