Science News

Exploding Star Kicked Early Humans Onto Two Legs

A team of German scientists examining material from the seabed beneath the Pacific Ocean think that they may have uncovered an important clue to the processes that kick-started the evolution of mankind. Drilling 15,750 feet below the surface, Gunther Korshinek and his colleagues, from the Technical University of Munich, have found deposits, dating back about 3 million years, of a rare form of iron, called iron-60, which is normally only found in exploding stars. The discovery of these rare iron deposits indicates that a massive explosion occurred close to the earth, around the same time that our earliest ancestors evolved. The team believe that such an explosion would have bombarded the Earth, for up to 300,000 years, in cosmic rays sufficiently strong to alter the climate. At precisely this time in Africa the climate did change quite abruptly - it became drier, the forests retreated, and the savannah opened up. As they lost their forest homes, our ancestors were pushed out of the trees, on to the ground, and then up on to 2 legs.

31st Oct 2004