Palaeoproteomic and genetic insights into millennial-scale dairy consumption in Armenia.

Dairy products are a key component of diet in Armenia today, yet the origins of milk consumption, its historical development, and genetic adaptations related to milk digestion remain understudied. Here, we investigate the co-evolution of dairying practices and lactase persistence in Armenia through combined palaeoproteomic and genetic analyses spanning prehistory to the present. Our palaeoproteomic results provide direct evidence of milk consumption in prehistoric Armenia and, with existing regional data, indicate that dairying was an established component of the South Caucasus subsistence economy at least from the 4th millennium BCE. Milk proteins were predominantly recovered from high-altitude sites, suggesting that dairy consumption may have served as an adaptive strategy in highland environments. In contrast, genetic findings indicate that lactase persistence-associated variants never reached high frequencies throughout Armenian prehistory. This may reflect cultural adaptation to fermenting dairy products, reducing lactose content and enabling dairy consumption in genetically lactose-intolerant populations.