Neanderthals may not have been the exclusive meat-eaters we once presumed. Analysis of nitrogen isotope ratios in their bones suggests a diet predominantly consisting of meat. Yet, these ratios could also result from a more varied, omnivorous intake that involved significant consumption of maggots.

“Trout pieces are readily accessible, nutritious resources,” notes Melanie Beasley from Purdue University in Indiana.

Historical evidence indicates that maggots were eaten regularly across different societies, and she points out that some reindeer hunters today consider them a snack, intentionally cultivating specific maggot types. For instance, Casu Marzu, a cheese containing live maggots, is a Sardinian delicacy.

Nitrogen comprises two stable isotopes, nitrogen-14 and nitrogen-15. Lighter isotopes tend to be lost from organisms more readily than heavier ones, resulting in a higher nitrogen-15 to nitrogen-14 ratio as food progresses up the trophic levels.

By examining the isotopic ratios in collagen from fossilized bones, researchers gauge the dietary habits of carnivorous animals, which tend to exhibit higher ratios than herbivores. However, upon studying Neanderthal bones, researchers found unexpectedly high ratios, even surpassing those of lions and hyenas. “This led to the myth of Neanderthals as intense hunters of large game,” explains Beasley.

Nevertheless, many researchers challenge this theory. Notably, bones from early Homo sapiens exhibit similar nitrogen ratios. Moreover, these early humans could not survive on lean meat alone. “It’s physically impossible,” Beasley states. “You’d suffer from what early explorers termed ‘rabbit starvation.’”

The dilemma lies in the fact that an excessively protein-rich diet can overwhelm the body’s ability to eliminate harmful byproducts like ammonia.

Moreover, significant direct evidence from dental calculus studies confirms that Neanderthals also consumed plant matter. So why is their nitrogen-15 ratio so elevated?

In 2017, John Speth at the University of Michigan proposed that Neanderthals might have stored their meat and consumed it in a decomposed state. When meat rots, it releases gases such as ammonia, which should lead to an increased nitrogen-15 concentration.

At that time, Beasley sought to conduct research at the University of Tennessee’s Body Farm, where human decomposition studies help in forensic investigations. There, she observed maggots feeding on corpses.

With Speth and Julie Lesnik from Wayne State University in Michigan, Beasley discovered that while nitrogen isotopic ratios do rise as muscle tissue decays, the increase is more pronounced in various types of maggots feeding on decomposing bodies.

While these findings are preliminary, they suggest that a purely meat-centric diet may not fully account for the nitrogen isotopic ratios seen in Neanderthals and early Homo sapiens, claims Beasley. She theorizes that these ratios may result from a blend of factors, including meat storage, preparation, cooking, and maggot consumption.

“This is an exciting new study that could significantly enhance our understanding of the perplexing results that have arisen from isotopic studies of Neanderthals and other Stone Age hominins over the years,” asserts Herman Ponzer from Duke University in North Carolina.

“The evidence here is quite persuasive that the consumption of maggots and similar larvae could clarify the ‘hypercarnivore’ indicators noted in past fossil isotope investigations,” he affirms.

Furthermore, this research supports the notion that the so-called Paleolithic diet should encompass rotten meat and maggots, according to Beasley. “Anyone interested in historical accuracy should consider fermenting meat and accessing fly larvae.”

Neanderthals, Ancient Humans, Cave Art: France

Join new scientist Kate Douglas as she embarks on an intriguing journey through time, exploring significant Neanderthal and Upper Paleolithic sites across southern France, from Bordeaux to Montpellier.