Why Modern Europeans Turn Up Their Noses at Bugs, But Neanderthals Didn’t

Insects are, by most measures, an excellent food. They pack in protein, need a fraction of the land and water that livestock does, and over 1,600 species are already recognized as edible somewhere on Earth. Hundreds of millions of people eat them regularly. And yet in most of Europe and the wider West, the idea of biting into a cricket or a grasshopper still provokes a shudder rather than an appetite. A new study in Science Advances suggests that reaction might be older, and more biological, than we assumed.

Researchers from the Institute of Evolutionary Biology, a joint center of the Spanish National Research Council and Pompeu Fabra University, went looking for direct evidence of ancient insect-eating. Their tool of choice was dental calculus, the calcified plaque that builds up on teeth and, crucially, traps and preserves DNA from whatever its owner was chewing on. The team screened 745 samples of this ancient tartar, taken from modern humans who lived as far back as 33,000 years ago, alongside comparative samples from Neanderthals, chimpanzees, and gorillas.

A Diet Poor in Bugs, for a Very Long Time

The results were fairly one-sided. Modern humans living across northern Eurasia carried only faint traces of insect DNA in their dental calculus far less than what turned up in Neanderthal samples, and well below the levels found in chimpanzees, who supplement their diet with insects, especially during lean seasons. Insect-eating, in other words, looks like it was occasional and largely incidental for our own species in this part of the world, rather than a deliberate dietary strategy.

The genetic side of the study backs this up. The researchers looked at chitinase genes, which produce enzymes that help break down chitin, the tough material that makes up insect exoskeletons. In northern Eurasian populations, these genes carry mutations linked to a reduced ability to digest chitin, and that genetic signature has held steady for roughly 9,000 years, since agriculture began reshaping how people ate.

“Pablo Librado, who led the study, frames it as evidence that the West’s aversion to eating insects isn’t just a matter of modern taste or culture, it appears to be rooted in a much longer ecological and evolutionary story.”

Neanderthals Ate More Bugs Than We Did

Neanderthals told a different story entirely. Despite living in many of the same landscapes as anatomically modern humans, their dental calculus held considerably more insect DNA, on par with the levels seen in western chimpanzees. The most common signals came from Diptera, the order that includes flies and mosquitoes, with mosquito DNA showing up especially often.

That detail lines up with a hypothesis some researchers have floated before: that Neanderthals regularly ate animal carcasses that had already attracted fly larvae, and may even have stored meat in ponds or marshy spots, environments where mosquitoes would have happily laid their eggs alongside it. The genetics reinforce the picture, Neanderthal chitinase genes look built for more efficient insect digestion, a trait also seen in the single Denisovan specimen included in the analysis.

Geography Left Its Mark on Our Genes

Zooming out to modern populations, the pattern holds: people living closer to the tropics are more likely to carry gene variants tied to stronger expression of the chitin-digesting enzymes chitinase acid and chitobiase. First author Manuel Piñero points out that tropical environments simply make insect-eating worthwhile, social insects like termites and locusts exist in the kind of biomass and year-round abundance needed to offset the energy spent gathering them, with the added bonus of natural pest control.

As populations spread toward higher latitudes, where insects are scarcer and harder to collect in bulk, expression of those digestive enzymes gradually faded. That geographic split has persisted for at least nine millennia, and it looks less like a cultural quirk and more like biology quietly following ecology.

Could Bugs Make a Comeback?

None of this necessarily closes the door on insects as food in the West. Modern processing can extract the nutritional value of insects without requiring anyone to chew through much chitin, and industrial-scale insect farming sidesteps the collection problem that shaped ancient diets in the first place. The same research group is now studying how insect domestication is unfolding, comparing the genomes of farmed insect species against their wild, pre-domestication relatives.

It’s a neat illustration of how deep some of our food preferences run, and a reminder that closing the gap between “sustainable protein source” and “dinner” might take more than just a good recipe.

Original paper: Piñero, M. & Librado, P. (2026). Genomic evidence for limited entomophagy in ancient Europeans. Science Advances, 12(23). 

Source: Why Modern Europeans Turn Up Their Noses at Bugs, But Neanderthals Didn’t