Ancient Agriculture and Genetic Diversity.

            This paper presents a brief introduction to archaeobotany and outlines the multiple ways in which archaeobotany and genetic diversity intersect. Archaeobotany, the study of human interactions with plants in antiquity, is a prime tool for investigating ancient agricultural practices. Carbonized plant remains can be preserved on archaeological sites for tens of thousands of years and can be systematically recovered from ancient deposits using a simple flotation procedure. By combining archaeobotanical theory with ecological theory, the presence of crop plants and associated weed assemblages can be used to infer ancient agronomic practices. Archaeobotanical research is enormously varied in scope but is often used to investigate: 1) the timing and nature of the shift from hunting and gathering to agriculture; 2) the drastic social changes that accompanied early agriculture; 3) the intensification of farming that provided the foundation for the earliest cities; 4) the diversity of food crops that were grown in the past as well as the methods of production; and 5) the dynamic relationship between climate change and food production. Identifications of ancient plant remains are secured by morphological comparisons with modern-day counterparts, so the ability to address these questions rests, in large part, on the availability of genetically diverse botanical comparative material. Consequently, current genetic diversity helps us investigate the past. The converse is also true. Recent improvements in studies of ancient DNA have enhanced our understanding of the genetic diversity of crops in antiquity. In instances where certain strains are no longer grown or have become extinct, knowledge of genetic diversity in the past helps us understand how crops have evolved through time, thereby allowing for a fuller understanding of modern-day genetic diversity.