A breakthrough genomic study published in Nature Ecology & Evolution has sequenced the DNA of 8,000-year-old human remains from the Oaxaca Valley in Mexico, uncovering the earliest known genetic adaptations to a maize-heavy diet. The research identifies specific alleles related to carbohydrate metabolism that began appearing as early as 6000 BCE, coinciding with the initial phases of teosinte domestication. This genetic shift provides a precise biological timeline for the transition from foraging to sedentary maize agriculture in Mesoamerica.
The study, led by an international consortium of paleogenomicists, suggests that the selection pressure for these metabolic traits was intense, rapidly altering the genetic landscape of the region's inhabitants. This finding challenges previous archaeological models that suggested a much slower integration of maize as a primary caloric source. Furthermore, the analysis reveals a high degree of genetic continuity between these early cultivators and modern indigenous populations in southern Mexico, highlighting the deep roots of Mesoamerican heritage.