A skeleton of a seven-and-a-half year old boy who died 49,000 years ago has revealed new insights into Neanderthal growth.
A study of his bones suggests our extinct cousins were slow to grow up, just like modern children.
But owing to their different physiology – such as a larger brain case – Neanderthal children showed some unusual growth patterns.
For instance, Neanderthals had a slightly more extended period of brain growth than modern humans.
The child’s brain was roughly 88 per cent the size of an average adult Neanderthal whereas modern humans tended to have on average 95 per cent of adult brain weight by that age.
Overall, the study suggests Neanderthals and modern human growth patterns are surprisingly similar – a discovery that adds to our understanding of human evolution.
The well-preserved skeleton, dubbed El Sidrón J1, was found in a Spanish cave of the same name in the 1990s along with a dozen of his family members.
Researcher Antonio Rosas and colleagues from El Museo Nacional de Ciencias Naturales studied the specimen, dubbed had mix of baby and adult teeth.
This provided them with a rare opportunity to estimate the age at death by looking at small markings preserved in teeth.
They believe the boy died at 7.69 years of age and analysis reveals some of the vertebrae had still not fused properly.
Yet these same vertebrae tend to fuse in modern day humans around the ages of four to six.
‘Prolonged brain growth is a way to distribute energy during a longer period which makes growth easier’, Dr Rosas said.
Dr Rosas said that researchers do not currently know if this would have meant they remained child-like for longer.
But the research suggests that the extended development of brain and spinal growth was a result of Neanderthals’ unique body form and physiology.
‘The brain is an expensive organ which demands energy for growing and working.
‘This is the biological strategy that higher primates – especially humans – have developed in evolution’.
The brain of El Sidrón J1 was roughly 87.5 per cent of the size of an average adult Neanderthal brain upon death, whereas modern humans tend to have on average 95 per cent of adult brain weight by that same age.
While there are some differences in terms of growth, overall, the similarities in delayed development between Neanderthals and modern humans is striking.
Humans have a fairly slow life development compared to some other primates.
Chimps, for instance, usually have their first child at 14.
But because human brains have more time to develop, they have more time for learning – and this was also the case for Neanderthals.
Research released earlier this month revealed Neanderthals survived much longer than previously thought.
Previous research suggested that the ‘Vindija Neanderthals’ living in Vindija Cave in northern Croatia lived as recently as 32,000 years ago.
But a new radiocarbon dating method has found that these remains were actually more than 8,000 years older than this initial estimate.
This means the Neanderthal group died just before the arrival of modern humans in Europe, the researchers, from the University of Oxford, claim.