Based on three fossilized baby teeth, researchers at the Università di Bologna have discovered that Neanderthals raised their children much like we do today. The team found that Neanderthal children were surprisingly similar in how they developed and also in how they were weaned off their mother’s milk.
“The beginning of weaning relates to physiology rather than to cultural factors,” said study co-first author Alessia Nava. “In modern humans, in fact, the first introduction of solid food occurs at around 6 months of age when the child needs a more energetic food supply, and it is shared by very different cultures and societies. Now, we know that also Neanderthals started to wean their children when modern humans do.”
A combination of geochemical and histological analyses of the teeth revealed that they belonged to three different Neanderthal children who lived between 70,000 and 45,000 years ago in a small area of Northeastern Italy.
Just like trees store a record of environmental data in their tree rings, teeth register information in their growth lines. Using various techniques to access this information, the scientists were able to show that the Neanderthal children had been introduced to solid foods at around 5 to 6 months of age.
“In particular, compared to other primates, it is highly conceivable that the high energy demand of the growing human brain triggers the early introduction of solid foods in child diet,” said study co-first author Federico Lugli.
Despite the fact that Neanderthals are closely related to Homo Sapiens, there has been a lot of uncertainty regarding their pace of growth and early life metabolic constraints.
“This work’s results imply similar energy demands during early infancy and a close pace of growth between Homo sapiens and Neanderthals. Taken together, these factors possibly suggest that Neanderthal newborns were of similar weight to modern human neonates, pointing to a likely similar gestational history and early-life ontogeny, and potentially shorter inter-birth interval,” explained study co-senior author Stefano Benazzi.
The three baby teeth analyzed for the study were found between the modern-day provinces of Vicenza and Verona in the Broion Cave, Fumane Cave and the De Nadale Cave. Using time-resolved strontium isotope analysis, the scientists collected data on the movement of these particular Neanderthals.
“They were less mobile than previously suggested by other scholars,” said study co-senior author Wolfgang Müller. “The strontium isotope signature registered in their teeth indicates in fact that they have spent most of the time close to their home: this reflects a very modern mental template and a likely thoughtful use of local resources.”
The study is published in the journal Proceedings of the National Academy of Sciences.