Researchers may have uncovered the secret to the demise of the Neanderthals and it may have been diet-based. Though Neanderthals lived thousands of years throughout western Eurasia, they mysteriously went extinct 40,000 years ago. Yet, modern humans, Homo sapiens, who coexisted toward the end of that time period, survived. Researchers were perplexed because Neanderthals seemed better adapted to the environment, but modern humans had an unknown advantage.
The Neanderthal lineage developed successfully throughout western Eurasia and effectively survived the harsh and severely changing environments of the alternating glacial/interglacial cycles from the middle of the Pleistocene until Marine Isotope Stage 3. Yet, towards the end of this stage, at the time of deteriorating climatic conditions that eventually led to the Last Glacial Maximum, and soon after modern humans entered western Eurasia, the Neanderthals disappeared. Western Eurasia was by then exclusively occupied by modern humans.
The new study compares dental wear patterns to environmental/climatic changes. Researchers analyzed the microwear textures in the fossilized molars of 52 Neanderthals and Homo sapiens from 37 Paleolithic sites across western Eurasia. They compared the wear patterns with paleoclimate data. The study explains,
Microwear texture analysis presents a proxy for the inference of dietary variations among Paleolithic hominin groups. The link between dental microwear textures and the mechanical properties of ingested items has been well-established through the examination of a variety of extant mammal species with well-documented diets. Several surface texture attributes – complexity, anistropy, texture fill volume, scale of maximum complexity, and the heterogenerty – have proven useful for the overall characterization of diets.
High-resolution dental casts were prepared for all of the specimens and they were analyzed using Toothfrax and SFrax software. Each specimen was assigned one of three paleoecological categories – open, mixed or wooded. They were compared to available paleoclimate/paleoenvironmental data from the same sites where the fossils were found.
Analysis of the data suggested that within the “Neanderthal lineage microwear signatures,” their diet was associated with paleoecological/climatic conditions. In the Homo sapiens of the same time period and environment, there was no significant correlation between diet and the environment.
An earlier study states that Neanderthals derived 80% of their diet from animals and 20% from plants. This study also shows that the Neanderthal’s diet was comprised mostly of meat they hunted while on the steppe environment, only adding plants and seeds if they were in a wooded area. Homo sapiens, on the other hand, retained a large portion of a plant-based diet and created tools to help them maintain this diet. Both Neanderthals and humans hunted the same scarce game during this time period.
El Zaatari says,
To be able to do this, they (Homo sapiens) have developed tools to extract dietary resources from their environment.
The results of the study show that the differences in subsistence strategies and use of available resources during climatic fluctuations gave modern humans an advantage over the Neanderthals and assured their survival. Survival of the fittest.