Rethinking Neanderthals: Survival, Genetics, and Changing Views

For decades, we have known about Neanderthals: our close evolutionary cousins who lived across Europe and parts of Asia before modern humans (Homo sapiens) spread across the globe. 

First discovered in the 19th century, Neanderthals were initially viewed as a primitive and less advanced species, distinct from us in ways that suggested they lacked the intelligence or adaptability needed for survival. However, as research has evolved, so too has our understanding of Neanderthals. Far from the brutish stereotypes once associated with them, evidence now points to a species capable of complex tool use, cultural practices, and even compassion, as indicated by the care they provided for their sick and elderly.

Despite this emerging view of Neanderthals as a sophisticated species, they did not survive the Pleistocene era, while modern humans did. Numerous theories have been proposed to explain why Homo sapiens thrived while Neanderthals disappeared around 40,000 years ago. One idea is that modern humans had superior cognitive abilities, allowing for more complex social structures, better communication, and more efficient use of resources. Others suggest that Homo sapiens were more adaptable to changing climates and ecosystems, giving them an edge as the environment fluctuated. Still, another theory posits that competition between the two groups for resources may have been a contributing factor to Neanderthal extinction.

However, Neanderthals did not vanish without leaving a trace. Genetic studies have revealed that modern humans of non-African descent carry between 1% and 4% of Neanderthal DNA, suggesting that interbreeding occurred between the two species during periods of contact. This genetic legacy indicates that Neanderthals were not completely replaced by modern humans but instead contributed to the gene pool, perhaps even passing on traits that proved beneficial to our survival.

Our perception of Neanderthals has shifted dramatically over the last few decades. The long-held view of Neanderthals as unintelligent brutes has been overturned by discoveries highlighting their capacity for art, symbolic thought, and emotional depth. We now know they buried their dead, created tools tailored for specific tasks, and may have even communicated using language. These revelations have reframed Neanderthals as a species that shared many characteristics with modern humans, blurring the lines between us and them.

In light of these changes in understanding, a recent study aimed to examine the differences in stress levels between Neanderthals and Upper Paleolithic modern humans (UPMH), seeking to uncover clues about their respective challenges during development. By analyzing enamel hypoplasia—growth disruptions in dental enamel caused by physiological stress—the study compared the two groups to see if Neanderthals experienced more difficult childhoods than UPMH. The results were striking, as they revealed that both Neanderthals and UPMH experienced similar levels of stress during childhood. However, the study also found differences in the timing of stress episodes. Neanderthal children appeared to suffer higher stress levels after the weaning period, while UPMH children faced their most significant stress early in childhood but then saw a decline in stress as they aged.

This nuanced finding challenges the notion that Neanderthals were inherently less capable of handling environmental or physiological stress compared to modern humans. Instead, it suggests that the timing and nature of their stress may have been different, possibly pointing to differences in social behavior, resource allocation, or even cultural practices between the two groups. These insights add to the growing body of evidence that Neanderthals were not as different from us as once thought, and they invite further investigation into what ultimately led to their extinction while modern humans continued to flourish.