National Geographic : 2008 Oct
JDMPI(LEFT). (ABOVE) SThe perfect teeth in a 42,000-year-old jawbone from Le Moustier in France offer an opportunity to probe into the nature of Neanderthal adolescence. Scientists penetrated the upper right canine with x-ray beams generated in a synchro tron particle accelerator in Grenoble, France, revealing daily growth lines (bars) between thicker eight-day bands (arrows) in the tooth's enamel. The evidence pinpoints when the subject died, sometime right before or after his 12th birthday. For a young person, the molars were quite well developed, suggesting shorter childhoods for Neanderthals-and less time for brains to develop in the context of the social group.