Dietary adaptation in Neandertal, Denisovan and Sapiens revealed by gene copy number variation

Dietary adaptation is the acquisition of an efficient system to digest food available in an ecosystem. To find the genetic basis for human dietary adaptation, we searched 16 genomes from Neandertal, Denisovan and Early Sapiens for food digestion genes that tend to have more or fewer copies than the modern human reference genome. Here, we identify 11 genes, including three gene clusters, with discernible copy number variation trends at the population level. The genomic variation shows how metabolic pathways for lipid, brown fat, protein or carbohydrate metabolism adapt to metabolize food from animal or plant sources. Interpreting the copy number profiles in relation to fossil evidence shows that Homo sapiens had an evolutionary advantage compared to Neandertal and Denisovan in adapting to cold and temperate ecosystems.