Skip to content
News / March 19, 2009

No monkeying around with oral health

by Guy Hiscott

Researchers in Japan have observed macaque monkeys show their offspring how to clean their teeth using fibres such as human hair stolen from tourists.

The team, led by Nobuo Masataka, a professor at Kyoto University’s Primate Research Institute in Aichi Prefecture, recorded 100 examples of this behaviour by seven adult female crab-eating macaques, half with their one-year-old infants watching and half without.

The overall duration of each teeth-cleaning session was about the same whether or not the infants were present. However, when they were watching, the mothers flossed for about twice as long and twice as many times.

Professor Masataka said: ‘They probably exaggerate their behaviour to allow their infants to learn how to clean their teeth more easily.

‘The study is still at the hypothesis stage. We would like to shift our focus to the baby monkeys to check whether the mothers’ actions are effectively helping them learn how to clean their teeth.’

The research has been published in the online edition of US science journal PloS One. For further information, visit