| Was oral hygiene the earliest human 
      custom?November 05 2003 at 02:06PM
         London - An American scientist may have settled a conundrum that could 
      have widespread implications about the customs, diet and oral health of 
      early humans - did they use toothpicks?
 Curved grooves on the roots 
      of teeth from ancient hominids suggest they were indeed concerned about 
      dental hygiene and used implements to pick their teeth.
 
 But critics 
      of the hypothesis have pointed out that modern humans who regularly use 
      toothpicks do not have similar grooves.
 
 Leslea Hlusko, a 
      palaeontologist at the University of Illinois at Urbana-Champaign, 
      believes grass stalks were used as toothpicks by early humans and made the 
      distinctive dental grooves.
 
 "Unlike wood, grass contains large 
      numbers of hard, abrasive silica particles. This may explain the grooves 
      seen on ancient teeth," New Scientist magazine said on 
      Wednesday.
 
 To prove the point, Hlusko ground a piece of grass along 
      a tooth from a baboon and also on a human tooth.
 
 "In both, the 
      grass left marks almost identical to those seen in scanning electron 
      microscopic images of early hominid teeth," the magazine 
      said.
 
 Dental grooves have been found on fossil teeth dating back 
      1.8 million years. If it was made by toothpicks it could qualify as the 
      oldest human custom yet recorded, according to New Scientist.
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