Abstract
Seagrass meadows are at the structural basis of highly diverse and productive ecosystems, providing a great number of goods and services. Their decline worldwide is thus a source of concern and it is crucial to understand the drivers of resilience in such foundation species. Genetic variation is considered a key to evolutionary adaptation and survival in the long term. However, the ecological and evolutionary success of clonal lineages, challenges the direct relationship between genetic diversity and adaptation. For example, in the seagrass Zostera marina large, old clones show high phenotypic plasticity in the absence of genetic variation. The key to this paradox may be the epigenetic variation (molecular-level changes altering gene expression, but not the DNA sequence). Even in the absence of genetic variation, epigenetic variation can cause heritable variation in phenotypic traits and thus can play a crucial role for an organism s immediate and evolutionary response to its environment. Nonetheless, we know very little about the importance of epigenetic processes in natural populations and many questions remain to be answered to fully appraise the role of epigenetics in plasticity and adaptation. Our proposal will use state of the art genomics techniques in combination with field survey and common garden experiments to address the importance of epigenetic variation for the resilience of Zostera marina. The objectives of the project are 1) to investigate the presence and drivers of epigenetic diversity within Zostera marina clones; 2) to assess the functional consequences of epigenetic variation in Zostera marina clones; and 3) to investigate the heritability of epigenetic variation within Zostera marina meadows. The project will fill fundamental knowledge gaps in the role of epigenetic versus genetic diversity as drivers of ecosystem resilience.
Norway