Neanderthal tartar holds insect DNA at levels seen in savanna chimpanzees

Dental calculus is an honest recorder with a bias built into it. It traps DNA from species eaten repeatedly ^[4], which makes a positive signal informative and a thin signal ambiguous: little insect DNA can mean insects were not eaten, or that they were eaten in forms and amounts that left little behind. The authors' own hedge, that consumption in Europe, Central and East Asia was probably occasional and accidental ^[5], fits comfortably inside that gap.

The dating comes from the genetics, not the teeth. The relevant genes act in the stomach, producing chitinase acid and chitobiase ^[13], and the North Eurasian versions carry mutations associated with a reduced ability to break down exoskeleton, a pattern that has held for about 9,000 years, back to the arrival of farming ^[6]. That coincidence cuts both ways. Loss-of-function variants that settle in as agriculture spreads look like a record of a diet that had already changed rather than a reason it changed. Pablo Librado, who led the work, frames it as evidence that the absence of entomophagy owes itself not solely to recent cultural factors but also to a long ecological and evolutionary history ^[7], which is a statement about sequence rather than about anything happening in a living gut.

Then there is the mismatch in windows. Nine thousand years is roughly 27 percent of 33,000 ^[17], so the enzyme evidence speaks to about the most recent quarter of the calculus record, and tartar carries the earlier three quarters by itself.

The Neanderthal result is the more concrete one, and it also invites a deflationary reading. If the signal comes mostly from larvae in carcasses and from mosquitoes that had laid eggs in the standing water where prey may have been stored ^[10][11], those insects arrived on the meat. The gap between Neanderthals and northern Eurasian modern humans then becomes a difference in how much incidental insect matter each diet delivered, which is a more modest claim than a taste for insects, and a more testable one.

The thing this doesn't tell you is whether the reduced-function genotype produces any noticeable effect at the doses in a modern insect-protein product, or whether chitin survives the processing at all. The FAO's interest in the 1,611 species classified as edible ^[15] meets refusal in Western markets ^[16], and refusal is a preference. No chitinase assay reads a preference, which is why the strongest version of this paper is the one it makes: a reconstructed history of exposure, with appetite left open.