Like all mammals, the Neanderthals breast-fed their babies. Scientists wanted to know: For how long? Today in Nature, a team of researchers, including several from UC Berkeley, say they’ve answered that question by looking at the fossilized tooth of an eight-year old Neanderthal child, discovered in a Belgian cave. Asa Bradman is an environmental health scientist at UC Berkeley and a co-author on the paper. He says teeth are like a time capsule.