Neanderthal kids grew teeth faster than human kids

2007-12-05 02:59:37 Xinhua English

BEIJING, Dec. 5 (Xinhuanet) -- The Neanderthal has been grabbing a lot of headlines recently, now comes news a recent analysis reveals the teeth of Neanderthal children grew faster than the teeth of human children today, suggesting a long childhood and slow development are uniquely human traits.

Tooth development in all primates, specifically the age of molar eruption, is related to other developmental landmarks, such as weaning and first reproduction. Anthropologists have long debated the timing of such events in Neanderthals, with evidence both supporting and refuting the idea that our distant cousins grew up differently than we do.

To get a better handle on Neanderthal tooth development, anthropologists at the Max Planck Institute in Germany examined the growth lines on the teeth of a 100,000 year-old juvenile found in the Scladina caves of Belgium.

They discovered the duration of tooth growth was shorter for the Neanderthal compared to modern humans. This faster growth rate resulted in a more advanced pattern of dental development than in members of our own species. In other words, the Neanderthal child grew teeth over a shorter period of time and had more teeth present in its mouth than similarly-aged fossil and living humans.

The Neanderthal child in the study appeared developmentally similar to a 10- to 12-year-old human, but is estimated to be only about 8 years old at the time of its death.

This new evidence, detailed in the Dec. 3 online edition of the journal Proceedings of the National Academy of Sciences, suggests that other aspects of physical development were also likely more rapid in Neanderthals than in humans (Homo sapiens), indicating that the slow development and long childhood of humans today is a recent condition uniquely evolved to our species.

(Agencies)