Genomic evidence for limited entomophagy in ancient Europeans.

To meet the rising food demands of our growing population, the Food and Agriculture Organization proposed edible insects as sustainable sources of animal protein. Although hundreds of million people already consume insects around the tropics, western societies remain averse to entomophagy. To trace whether ancient Europeans consumed insects, we here apply two complementary genomic approaches. Metagenomic screening on 745 ancient anatomically modern human dental calculus returned limited insect DNA traces, with read abundances well below those observed in Neanderthals, western chimpanzees, and gorillas. In addition, genes encoding stomach-expressed chitinases show two of the most significant signatures of latitudinal differentiation genome-wide. Clines are consistent with evolutionary benefits of entomophagy in tropical regions and with expression quantitative trait locus data supporting low chitin digestibility in present-day Europeans. Ancient genomes confirm that both clines already existed at the onset of agriculture and persisted despite massive migrations. Together, our findings support occasional and possibly incidental insect consumption in Europe over the past ~9000 years.