Abstract Detail

Reproductive Processes

Valverde, Javier [1], Medrano, Mónica [1], Alonso, Conchita [2], Herrera, Carlos [3].

Pollinator diversity as key element to better understand population genetic diversity in restricted endemic plant species.

Comparisons of related species with contrasting geographical distributions provide valuable insights to understand the consequences of rarity and to predict their evolutionary responses to changing environmental conditions. In particular, rare, endemic or geographically restricted species are typically considered to maintain low levels of genetic variation when compared to their widespread congeners, although empirical support for this prediction has not always been found. This lack of a generalized pattern points to the need to examine additional ecological covariates directly related to gene flow to better understand plant population genetic diversity. In entomophilous species the diversity of pollinator assemblage together with its abundance might explain in part such patterns. Indirect studies suggest that endemic species might be less attractive to pollinators, however there are no direct studies comparing pollinator diversity or visitation rates between congeneric pairs of widespread and restricted species, nor examining the potential differences in their correlations with the genetic diversity of populations.
We compared the characteristics of pollinator assemblages and their relationship with the genetic diversity and distinctiveness of plant populations in five congeneric pairs of plant species consisting on a widespread and a restricted endemic species in the same Mediterranean region in southeast of the Iberian Peninsula. We used AFLP markers to characterise the genetic features in two to three populations per plant species. In addition, we performed an exhaustive study of the pollinator assemblage in each population assessing the visitation rates and the pollinator diversity profiles.
All plant species showed high genetic diversity regardless of their distribution range. Overall, the probability of visitation was higher in widespread species, although the magnitude of the difference depended on the specific pair considered. In contrast, we did not find differences in pollinator diversity between widespread and endemic species in pollinator diversity. Despite this finding, only endemic species showed any association between the pollinator assemblage and the genetic descriptors. Specifically, both the visitation probability and the pollinator richness had a significant positive relationship with the genetic diversity.
Our results suggest that the genetic diversity in populations from restricted endemic species may be more sensitive to variations in the pollinator abundance and richness than in those from widespread species. This study highlights the need to include pollinators observation in studies searching for common patterns in the adaptations of plant species to contrasting distribution ranges.

1 - Estación Biológica de Doñana, CSIC, Evolutionary Ecology, Avenida Américo Vespucio, 26, Sevilla, SE, E41092, Spain
2 - Estacion Biologica De Doñana, Evolutionary Ecology, Avda Americo Vespucio 26, Sevilla, SE, E-41092, Spain
3 - Estacion Biologica de Doñana, CSIC, Evolutionary Ecology, Avda Americo Vespucio 26, Sevilla, SE, E-41092, Spain

population genetics
Mediterranean ecosystems
Endemic Species
plant-pollinator interactions.

Presentation Type: Oral Paper
Number: RP4006
Abstract ID:667
Candidate for Awards:None

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