Data from: Mismatch in the distribution of floral ecotypes and pollinators: insights into the evolution of sexually deceptive orchids

Dataset

Description

Plants are predicted to show floral adaptation to geographic variation in the most effective pollinator, potentially leading to reproductive isolation and genetic divergence. Many sexually deceptive orchids attract just a single pollinator species, limiting opportunities to experimentally investigate pollinator switching. Here we investigate Drakaea concolor, which attracts two pollinator species. Using pollinator choice tests, we detected two morphologically similar ecotypes within D. concolor. The common ecotype only attracted Zaspilothynnus gilesi, while the rare ecotype also attracted an undescribed species of Pogonothynnus. The rare ecotype occurred at populations nested within the distribution of the common ecotype, with no evidence of ecotypes occurring sympatrically. Surveying for pollinators at over 100 sites revealed that ecotype identity was not correlated with wasp availability, with most orchid populations only attracting the rare Z. gilesi. Using microsatellite markers, genetic differentiation among populations was very low (GST = 0.011) regardless of ecotype, suggestive of frequent gene flow. Taken together, these results may indicate that the ability to attract Pogonothynnus has evolved recently but this ecotype is yet to spread. The nested distribution of ecotypes, rather than the more typical formation of ecotypes in allopatry, illustrates that in sexually deceptive orchids pollinator switching could occur throughout a species’ range, resulting from multiple potentially suitable but unexploited pollinators occurring in sympatry. This unusual case of sympatric pollinators highlights D. concolor as a promising study system for further understanding the process of pollinator switching from ecological, chemical and genetic perspectives.,D concolor broad scale surveysLatitude and longitude of survey locations of the pollinators of Drakaea concolor. Includes the number of wasps detected in surveysD concolor microsat scoresMicrosatellite scores for a population genetic study of Drakaea concolorD concolor pollinator choice trialsChoice trials with the wasp Pogonothynnus sp., responding to different populations of the orchid Drakaea concolorD concolor pollinator sizeComparison of the sizes of the two pollinators of Drakaea concolor, Pogonothynnus sp. and Zaspilothynnus gilesi,
Date made available22 Jan 2015
PublisherDryad Digital Repository

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