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★Dont wash those fossils! Standard museum practice can wash away DNA. 1.Washing，brushing and varnishing fossilsall standard conservation treatments used by many fossil hunters and museum curators alikevastly reduces the chances of recovering ancient DNA. 2.Instead，excavators should be handling at least some of their bounty with gloves，and freezing samples as they are found，dirt and all，concludes a paper in the Proceedings of the National Academy of Sciences today. 3.Although many palaeontologists know anecdotally that this is the best way to up the odds of extracting good DNA，Eva-Maria Geigl of the Jacques Monod Institute in Paris，France，and her colleagues have now shown just how important conservation practices can be. This information，they say，needs to be hammered home among the people who are actually out in the field digging up bones. 4.Geigl and her colleagues looked at 3，200-year-old fossil bones belonging to a single individual of an extinct cattle species，called an aurochs. The fossils were dug up at a site in France at two different timeseither in 1947，and stored in a museum collection，or in 2004，and conserved in sterile conditions at -20 C. 5.The teams attempts to extract DNA from the 1947 bones all failed. The newly excavated fossils，however，all yielded DNA. | 
