Detecting multiple origins of domesticated crops
Year: 2008
Type: article
Abstract: Crop domestication has long been studied both as a model for understanding the process of evolution (1) and for gaining insights into the history of human civilization (2). In recent decades, a wealth of neutral molecular markers (e.g., SNPs, microsatellites, amplified fragment length polymorphisms) has become available for many crop species, permitting genomewide examinations of genetic diversity in crops and their wild relatives. Quite commonly, these surveys reveal that the present-day representatives of a crop all show close genetic similarity to a specific geographical subset of a wild species (e.g., ref. 3; Fig. 1A); this pattern is typically interpreted as evidence that the crop was domesticated a single time and in a single geographical region. Interestingly, this picture of a single, geographically localized crop origin does not always match the picture inferred from archaeological data. In particular, for Old World cereal crops, archaeobotanical data have indicated that domestication was likely a geographically diffuse and protracted process, involving long-term predomestication plant use across wide areas of the Near East (4). As such, the present-day diversity of a crop might well be expected to reflect multiple, geographically disparate origins of domestication (Fig. 1B). Why then, do multilocus genetic studies reveal monophyletic origins of Old World cereal crops? A study by Allaby et al. (5) in this issue of PNAS suggests that, given certain population parameters, the genetic signature of a single origin can arise even if multiple domestication events have occurred.
Authors: Kenneth M. Olsen, Briana L. Gross
Institution: Washington University in St. Louis
Language: English
Subfield: Genetics
Domain: Life Sciences
SDG: Zero hunger
Open Access status: green
OpenAlex ID: W2013923295