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Science: Supernova blasts 'led to walking'

Supernovas, exploding stars, could have made human's ancestors start walking on two legs, according to a paper published on Tuesday. The study published in the Journal of Geology showed that supernova explosions bombarded the Earth with cosmic energy starting 8 million years ago, with a peak about 2.6 million years ago, bringing about an avalanche of electrons in the lower atmosphere. Those electrons triggered an enormous upsurge in cloud-to-ground lightning strikes that ignited forest fires around the globe, setting off a chain of events that ended with bipedal apes, such as homo habilis, dubbed "handy man" as they are believed to have been the first makers of tools.

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