Neanderthal babies appear to have spent their days much like human infants, with one major difference: They were weaned earlier, according to a new study.
The study, published in the latest issue of the journal Nature, suggests that Neanderthals lived faster and died younger than their human counterparts. That probably happened due to environmental constraints, such as cold temps and food sources, which influenced population growth and everything associated with it.
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"Weaning is critical to developmental and reproductive rates," wrote lead author and University of Sydney researcher Christine Austin. "Early weaning can have detrimental health effects but enables shorter inter-birth intervals, which influences population growth."
Researchers made the determinations after studying Neanderthal teeth. The scientists also looked at the teeth of human children and macaques for comparison.
The shift from weaning to solid food is locked into the structure of the tissues that exist in the tooth and in its roots. The evidence remains even if baby teeth are lost and replaced with permanent ones. In this study, the researchers analyzed a young Neanderthal's first molar tooth.
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The element barium, found in enamel, turns out to vary with the big dietary changes. Barium's distribution in tooth enamel rises during breastfeeding and drops quickly when the individual is weaned.
Barium levels indicate that the Neanderthal youth was breastfed exclusively for seven months, followed by seven months of supplementation. Breastfeeding then ceased and the individual began to eat, presumably with some help from its mother, parents or multiple relatives.
In comparison, prehistoric humans stopped breastfeeding when the children were between 2 and 4.
Neanderthal children had to mature faster than humans and would have received less guaranteed nutrition, which might have affected their mental and physical development.
Image: Measuring barium and calcium in a Neanderthal tooth showed a relatively early move to solid food. Credit: Ian Harrowell, Christine Austin and Manish Arora