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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