Why Did Neanderthals Go Extinct?

Modern man played an indirect role in the downfall of this ancient species.

Posted Feb 27, 2021 | Reviewed by Kaja Perina

  • Modern humans exhibited higher growth rates and migrated more quickly than did Neanderthals, thus permitting them to populate and repopulate areas more efficiently.
  • It is impossible to ascertain the degree to which environmental factors such as climate change or volcanic eruptions contributed to Neanderthals' extinction. 
  • Future research could focus on agent-based modeling of factors such as hunting techniques or pathogen resistance.

There’s no question that modern humans have been responsible for the extinction of countless species. Curiously, our competitive advantages could have spelled the end for Neanderthals, according to the results of a novel model analyzing hominin interactions in time-varying climate environments. Results of the study are published in a recent issue of Quaternary Science Reviews.

“Modern Humans are the sole survivor of a group of hominins that inhabited our planet during the last ice age and that included, among others, Homo neanderthalens, Homo denisova, and Homo erectus,” wrote Axel Timmermann. “Whether previous hominin extinctions were triggered by external factors, such as abrupt climate change, volcanic eruptions or whether competition and interbreeding played major roles in their demise still remains unresolved.”

Source: irstone/123RF

The author found that competitive exclusion likely played a key factor in the end for Neanderthals. In ecology, competitive exclusion is the principle that two species are unable to coexist in the same ecological niche for long before one becomes extinct due to competition for limited resources. A premise of competitive exclusion is that Anatomically Modern Humans (AMHs) were twice as good at utilizing extant food sources compared with Neanderthals.

Modern Humans' Advantages Included More Rapid Migration

Modern humans also exhibited higher growth rates and migrated more quickly, thus permitting them to repopulate areas more efficiently after a rapid decline in Neanderthal populations, due, for instance, to Dansgaard–Oeschger Events (D-O Events), which were rapid climate changes that occurred during the last glacial period. These repopulated areas had higher starting densities of Homo sapiens, which contributed to disadvantageous conditions for Neanderthals in terms of competition, according to the author.

Ultimately, although important regionally, abrupt climate change likely played only a limited role in the global decline of Neanderthals. Moreover, according to the model, interbreeding and assimilation, which are suggested as important factors in the death of the European Neanderthals, are effective only in decimating species in areas of low food competition.

The author also noted that modern humans had better tools at their disposal than did Neanderthals. Specifically, Homo sapiens possessed blades and bone/antler tools. Additionally, modern man may have exhibited better hunting skills, including the use of domesticated dogs, as well as enhanced resistance to pathogens arising from the African continent. (Homo sapiens migrated from Africa around 100,000 years ago.) Taken together, these factors could have proffered modern man a competitive advantage over Neanderthals, thus facilitating the process of competitive exclusion.

What We Know And What Future Studies Will Examine

Future research could focus on agent-based modeling or bulk-parameter modeling of factors including the social/cultural superiority of Homo sapiens, hunting techniques, or pathogen resistance.

The rapid extinction of Neanderthals happened between 35,000 and 50,000 years ago. It occurred after modern humans settled to subtropical and extratropical regions of Europe and Asia between 40,000 and 60,000 years ago. Neanderthals settled in climatically and environmentally restricted areas, and probably lived in smaller and more fragmented groups, according to previous research.

“This study confirms the notion that innovative generalists [Homo sapiens] with higher levels of mobility, fecundity and plasticity, outcompete specialists [Homo neanderthalens], who lived in smaller and more fragmented habitats,” the author concluded. “What specifically constituted the key competitive advantage of HS over HN is difficult to ascertain.”