title: Maize diversity associated with social origin and environmental variation in Southern Mexico.
abstract: While prevailing theories of crop evolution suggest that crop diversity and cultural diversity should be linked, empirical evidence for such a link remains inconclusive. In particular, few studies have investigated such patterns on a local scale. Here, we address this issue by examining the determinants of maize diversity in a local region of high cultural and biological richness in Southern Mexico. We collected maize samples from villages at low and middle elevations in two adjacent municipalities of differing ethnicity: Mixtec or Chatino. Although morphological traits show few patterns of population structure, we see clear genetic differentiation among villages, with municipality explaining a larger proportion of the differentiation than altitude. Consistent with an important role of social origin in patterning seed exchange, metapopulation model-based estimates of differentiation match the genetic data within village and ethnically distinct municipalities, but underestimate differentiation when all four villages are taken together. Our research provides insights about the importance of social origin in structuring maize diversity at the local scale.
authors.affiliation: Centro de Investigaciones en Geografía Ambiental, UNAM, Antigua Carretera a Pátzcuaro, Morelia, Michoacán, México.
authors.forename: Q
authors.initials: Q
authors.lastname: Orozco-Ramírez
authors.affiliation: Department of Plant Sciences, Center for Population Biology, and Genome Center, University of California, Davis, CA, USA.
authors.forename: J
authors.initials: J
authors.lastname: Ross-Ibarra
authors.affiliation: Colegio de Postgraduados. Montecillo, Texcoco, Estado de México, México.
authors.forename: A
authors.initials: A
authors.lastname: Santacruz-Varela
authors.affiliation: Department of Human Ecology, University of California, Davis, CA, USA.
authors.forename: S
authors.initials: S
authors.lastname: Brush
mesh_terms: D000383:Agriculture; D018556:Crops, Agricultural / Q000235:genetics; D004777:Environment; D005819:Genetic Markers; D014644:Genetic Variation; D005828:Genetics, Population; D008800:Mexico; D012639:Seeds; D003313:Zea mays / Q000235:genetics*
chemical_list: D005819:Genetic Markers