Ancient DNA from lentils (Lens culinaris) illuminates human - plant - culture interactions in the Canary Islands

Abstract

The intimate relationship between humans and crop plants means that traces of human cultural practices become embedded in the crop genome. Genetic analyses of archaeological crop remains thus allow cultural consequences of societal change to be studied. The Canary Islands have a unique cultural history where the Hispanic colonization in the 15th century led to eradication of the indigenous culture, partial replacement of the human gene pool and a rapid transformation of the islands into a globalization hub between the Old and the New World. Although many aspects of these events are well known, the interconnections between the cultural turnover and cultivated crops have rarely been studied. In this study full genome sequencing and KASP genotyping have, for the first time, been successfully carried out on millennium old seeds of lentil (Lens culinaris). Comparisons with present day lentils reveal that indigenous lentils were kept in continuous cultivation on the Canary Islands until the present. We suggest that this was facilitated by a gendered division of agricultural responsibilities and inheritance as well as adaptation to the local climate. We confirm a previously suggested long-term inter-island isolation prior to the arrival of Europeans and demonstrate continuous lentil cultivation also on islands where they were believed lost prior to the arrival of Europeans. The results furthermore hint to a role of Canarian lentils in the cultivation and consumption of lentils on the European mainland. To conclude, this first analysis of ancient lentil DNA show how understudied archaeological plant remains can reveal aspects of past cultures not documented in written records.