Researchers studying tooth wear patterns in ancient Homo reveal that – as climate began to fluctuate severely in the Ice Age – Neanderthals adapted their diets in a different way than our own species. The findings, published in PLOS One this week, suggest that human dietary strategies gave our species an edge over Neanderthals.
The Neanderthal lineage survived for hundreds of thousands of years throughout western Eurasia, successfully dealing with both harsh and changing environments. Why they went extinct some 40,000 years ago is still a mystery. Some researchers would expect Neanderthals to be better adapted than Homo sapiens – a species that evolved in Africa – to live in Europe during extreme climate instability. But, modern humans replaced Neanderthals, suggesting that our species had some survival advantage.
To investigate the influence dietary strategies had on Neanderthal decline, a team led by Sireen El Zaatari of Eberhard Karls Universität Tübingen analyzed microwear textures on the fossilized molars of 52 Neanderthals and Homo sapiens spanning 37 Paleolithic sites across western Eurasia. The team then correlated these patterns with paleoclimate data.
As fluctuating climate conditions changed ecosystems and habitats, Neanderthals took an opportunistic approach: They adapted their diet to resources that were readily available. That meant eating mostly meat in cold, steppe environments and adding some plants, seeds, and nuts when they were in wooded areas.
Meanwhile, anatomically modern humans stuck to their strategy and retained a large proportion of plants in their diet. "To be able to do this, they may have developed tools to extract dietary resources from their environment," El Zaatari said in a statement. Rather than alter their diets, our species invested in technological innovations.
These differences in subsistence strategies – which were established around the same time the two lineages made contact – may have helped our species persist despite changes in food supplies linked to half a million years of severe climatic fluctuations.