Life Cycle of a Primate's Bite
Do primates like chimps and apes have baby teeth that they lose?A. Humans are not unique in shedding and replacing their milk teeth, or deciduous teeth, and other primates do so for the same reason: They have different teeth for different diets at different stages of life.
There are three basic kinds of teeth: incisors, to bite and gnaw; canines, to stab and seize; and molars and premolars, to grind and chew. Like all mammals, primates initially feed on milk, and so need no teeth. As they begin to eat solid foods, the deciduous teeth emerge, to be gradually replaced by an assortment of permanent teeth.
In limited studies, according to "Primate Dentition: An Introduction to the Teeth of Nonhuman Primates," by Daris R. Swindler (Cambridge 2002), among all the apes orangutans show the greatest similarity to human beings with respect to their deciduous teeth.
Primate dentition has been studied for clues to development and evolution. The timing of emergence and loss of baby teeth, for example, is coordinated with the interval before weaning. In a 1989 study in The Journal of Human Evolution, gorillas were found to have a faster attrition rate for juvenile teeth than two other closely related primate species, orangutans and chimpanzees, suggesting to the researchers that weaning took place earlier in gorillas and possibly in fossil hominid species that showed a similar pattern, with implications for their reproduction rate. C. CLAIBORNE RAY
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