Italian-born Stefano Vanin, forensic scientist at the University of Huddersfield, is unmasking minute creatures which contaminate crime scenes and throw sleuths off the scent and into drawing erroneous conclusions. For example, ants which clamber over a corpse's face can deposit marks which mimic the effects of a punch. Other tiny creatures can cause lesions to a dead body which closely resemble injuries left by a human assailant, says Vanin, the journal Forensic Science International reports.

It was the retrieval of the body of a 28-year-old man in the River Brenta, at Padova in Italy, that provided Vanin with the opportunity to add another piece to his jigsaw of knowledge, according to a Huddersfield statement. The man had drowned - witnesses had seen him struggling in the water - and there were no signs of injury on the body. But during the autopsy, a series of small abrasions in the upper eyelids were discovered.