Making a positive impact
Sun, 16th Mar 2008
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from the show Cambridge Science Festival Highlights
Many people assume that meteors hitting our planet can only spell disaster for living creatures. For example, we’ve all heard about the massive meteor strike 65 million years ago that is widely believed to have done for the dinosaurs.
But scientists at the Natural History Museum of Denmark are now suggesting that in fact the opposite may be true, and that meteor strikes may in fact be beneficial for biodiversity and animal life.
Palaeontologists Svend Stouge and Dave Harper have been studying the so-called Ordovician period around 490-440 million years ago, a time when the earth was battered by more than 100 massive meteorites at one time. Surprisingly, the researchers found that after an initial negative impact on life, new and more varied species evolved in the oceans, which at that time were home to virtually all life on Earth. The researchers believe that the strikes gave evolution a serious boost in a relatively short period of time
Writing in the journal nature Geoscience, the researchers were studying meteorite craters in Sweden, such as the large Lockne crater, with a diameter of 7.5 km. Although at the moment their findings only apply to the region around the Baltic sea, the scientists say they have now found meteorites in southern China with the same chemical composition as those they studied in Sweden.
The team now plan to study craters and meteorites in China and the USA to find out whether the positive benefits of meteor strikes are a global phenomenon, which could have exciting implications for the entire history of evolution.