Prof Rosas and his team believe they are right and the previous studies are wrong because for the first time they were able to study a relatively complete skeleton of a child at a crucial stage in their development. “What we see in this Neanderthal is the general pattern of growth is very similar to that of modern humans,” said Luis Ríos, a paleoanthropologist at the National Museum of Natural History of Spain, during a news conference on Wednesday. MADRID, SPAIN—Live Science reports that the paleoanthropology group at Spain’s National Museum of Natural Sciences studied the rate of Neanderthal development by analyzing the nearly complete skeleton of a young male Neanderthal discovered at the site of El Sidrón. according to an analysis of a 49,000 year-old juvenile skeleton found in a cave in northwestern Spain.The analysis was conducted by a team led by palaeobiologist Antonio Rosas of the Museo Nacional de Ciencias Naturales in Madrid, and published in the journal The scientists found that the Neanderthal child, reliably established to have been 7.7 years old at death, had a brain that was about 87.7% the size of an adult. Comparing this Neanderthal’s brain size against the adult average for the whole of the Neanderthal species—as opposed to its own adult brain size, which we can never know since it died as a juvenile—is bound to result in shaky conclusions. "Neanderthals have a larger brain and larger body and so it is logical to think that the brain of the Neanderthal continues to grow for a little longer to allow their brains and bodies to get to their adult size," he explained. Analysis of a well-preserved 49,00 year-old Neanderthal child skeleton suggests vertebrae had still not fused by the age of almost eight years old, while the same vertebrae in humans tends to fuse between the ages of four and six. Modern humans and Neanderthals emerged from a common recent ancestor, and this is manifested in a similar overall growth rate," said Antonio Rosas, from Spanish National Research Council (CSIC).
A new study shows that Neanderthal brains developed more slowly than those of modern humans, contradicting previous studies.