Abstract Detail

Symbioses: Plant, Animal, and Microbe Interactions

Stephens, Jessica [1], Determann, Ron [2], Malmberg, Russell [1].

The Evolution of Plant Carnivory: Insights into Morphological Diversification and Prey Partitioning in the Carnivorous Pitcher Plant Genus Sarracenia.

Since Darwin, biologists have long recognized that ecological interactions among closely related species may be significant drivers of adaptive evolution and diversification of species. The role these interactions have in shaping rates and patterns of speciation and morphological divergence is therefore of interest in ecology and evolutionary biology. The North American carnivorous plant genus Sarracenia is a particularly attractive model system to investigate and enhance our understanding of how interactions between closely related species, specifically competition over a limited resource, have shaped diversification. These plants have evolved highly modified leaves (i.e. pitchers) used in attraction, trapping, retention, and digestion of insect prey to obtain nutrients. Moreover, carnivorous plants are highly dependent on insects to obtain nutrients, creating intense competition for prey among sympatric species. This competition scenario is predicted to cause strong selection on traits related to prey attraction potentially leading to resource partitioning and variation in trapping morphology. Here, we created a common garden containing the 11 species listed in Mellichamp and Case (2009) and 4 putative infraspecific taxa listed by Mellichamp and Case (2009) and McPherson and Schnell (2011). Preliminary data of insect prey communities collected from S. minor, S. minor var. okefenokeensis, S. flava, S. rosea, S. psittacina, and S. leucophylla indicate there are significant differences in prey captured across these six species/varieties. In addition, these prey community differences are correlated with height, trichome densities, and peristome width of pitchers. More specifically, taller pitcher plant species attract flying prey more often (e.g. Lepidoptera, Coleoptera, Hymenoptera, Diptera), while shorter pitcher plant species trap ground crawling prey (e.g. Formicidae, Diplopoda). These differences in prey communities may have been an important ecological driver of speciation in this genus. Future work will examine these leaf traits and prey communities within a phylogenetic context to further assess this hypothesis.

1 - University Of Georgia, Plant Biology, 2502 Miller Plant Sciences, Athens, GA, 30602, USA
2 - Atlanta Botanical Garden, Atlanta, GA, USA

Keywords:
Sarracenia
prey
ecological diversification
carnivorous plants.

Presentation Type: Poster:Posters for Topics
Session: P
Location: Eyrie/Boise Centre
Date: Monday, July 28th, 2014
Time: 5:30 PM
Number: PSB002
Abstract ID:448
Candidate for Awards:None