Raquel Ruiz-Checa

Centro Investigaciones Energéticas, Medioambientales y Tecnológicas | CIEMAT · Departamento de Medio Ambiente

Adaptation is one of the main responses of living beings to new environmental conditions. It has been argued that populations that occur at the range limits have great adaptive value as they are found under environmental conditions that are limiting for the species. Nevertherless, this is a controversial statement because it is foreseable that these populations present low genetic diversity on which natural selection can barely operate. The purpose of this project is to assess the processes of local adaptation in the populations of the southernmost limit of distribution of Silene ciliata Pourret (Caryophyllaceae), a plant of the psicroxerophilous pastures of the Mediterranean high mountains, representative of one of the most vulnerable habitats to global change in Spain. The project will analyze the relevance of population size, a key factor in this process. Taking into account possible conservation actions that may be taken to rescue marginal populations, the effect of center-periphery genetic flux on individual fitness of marginal populations will be compared with that of periphery-periphery genetic flux. Finally, the genes expressed during the establishment of Silene ciliata seedlings that may be involved in local adaptation processes will be identified and loci that are under selection will be detected and identified. The combination of field experiment approaches (common gardens with in situ reciprocal sowings), ecogeographical characterization based on field data and geographic information systems, and molecular and genomic techniques, including next generation sequencing, allow an integral perspective of local adaptation and the assessment of the relevance of this process when developing strategies that minimize the impact of global change on biodiversity.