Longer childhood and adolescence

As teeth develop, new enamel layers form daily. Scientists used CT-scanning to count the enamel layers on the 160,000 year old teeth of a 7-8 year old Homo sapiens child found at Jebel Irhoud, Morocco. The layers show that the teeth were growing and erupting at the same rate as those of seven- to eight-year-old children today, telling us that this fossil human child was growing at the same rate as living humans.