Generalización estructurada: Dinámica evolutiva a escala espacial fina en un sistema generalista

Abstract

The evolution of plant pollination systems is one of the main subjects of debate in the fore of pollination biology. Along the gradient of specializationgeneralization, generalist plants exist in higher frequencies than those expected by some theoretical expectancies. Plants with this pollination system exhibit great spatio-temporal variations in the pollinator assemblage that manifests at different scales, from the populational to the individual level. At the individual level this variation has been considered to be random and extent of any functionality. However, there exist evidences against this thought. We think that generalization might result from a pollinator-mediated evolution in what we have labeled structured generalization. In this hypothesis the individual level of generalization is associated to plant phenotype and genotype as a result of the different preferences of pollinators. The individual generalization will affect to the plant’s reproductive output and result in an assortative mating. Consequently, the populational genetic structure may be affected and phenotypic and genetic divergences may arise if this structure is maintain over time. In this study we explore the basis of the structured generalization from its causes to its effects on the population genetic structure. To do so, we use the generalist plant species Erysimum mediohispanicum (Brassicaceae) as a species model. In a natural population and in two experimental plots we monitorized a series of marked individuals during their flowering time. For each individual plant, we characterized its phenotype and microenvironment and surveyed all plant interactions with its pollinators along the flowering season. Additionally, we genotyped each marked individual as well as part of their progeny. Finally, we characterized the effectiveness of pollination of the different functional groups visiting the flowers of E. mediohispanicum.