Abstract Detail

Reproductive Processes

Rodriguez, Rosa [1], Wolfe, Andi [2].

Investigating the Agents Driving Floral Diversity in Penstemon Morphology, Climate, and Pollinator Data.

The interaction between flowers and the animals that pollinate them is one of the major drivers of diversification because it promotes reproductive isolation between closely related diverging taxa. Therefore, it is not surprising that approximately 85% of angiosperms are pollinated by animals. However, many plant species are also visited by pollen/nectar thieves that collect flower resources but do not pollinate. The influence of thieves on the evolution of flower morphology is controversial, and few studies have quantified the frequency of these illegitimate visitors. Therefore, little is known about how pollinators and thieves affect flower evolution, along with other abiotic factors such as climate and geographic distance. The main goal of this study is to determine whether flower morphology changes across a wide distribution range because of pollinator-mediated selection. Specifically, we had three questions: 1) Does geographic distance between locations influence flower variation? 2) Do environmental factors influence flower morphology? And 3) Do populations dominated by the same visitor class (true pollinators, thieves, etc.) have similar flower morphology? Five species of Penstemon (P. albidus, P. fruticosus, P. glandulosus, P. speciosus, and P. whippleanus) were used in this study. Our sampling covers the total distribution range of the five species in the U.S.A., and consisted on measuring 21 morphological traits, recording insect visitation, sampling of DNA tissues, and the extraction of 19 bioclimatic variables from Worldclim. Several R packages were used to analyze our data. Our results indicated that for all the species, changes in longitude were significantly correlated with corolla length and corolla mouth width. In three of the species, changes on visitor class were significantly correlated with changes in flower morphology. In two of the species, environmental changes were significantly correlated with morphological differences between sites. Finally, our results showed that flower visitors, other than pollinators, can affect flower morphology and that abiotic factors have a significant contribution to those changes as well.

1 - The Ohio State University, Evolution, Ecology and Organismal Biology, 318 W 12th Ave, Building 131, Columbus, OH, 43210, United States
2 - Ohio State University, Department Of Evolution, Ecology And Organismal Biology, 318 W. 12th Avenue, Columbus, OH, 43210, United States

flower morphology
geographic distance
spatial environmental variation.

Presentation Type: Oral Paper
Number: 0002
Abstract ID:790
Candidate for Awards:None

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