Kay, Elma , Bernhardt, Peter .
Passionflower pollination ecology and the utility of a phylogenetic approach.
Floral morphology and the concept of pollination syndromes has been used to predict pollination system. Species in the passionflower genus, Passiflora (Passifloraceae), show broad variation in floral presentation and morphology, particularly of the androgynophore and corona. Based on morphology, predictions can be also be made as to the pollination system in various passionflower species. While passionflowers have been demonstrated to exploit a range of pollination systems including bees, wasps, hummingbirds, or bats as pollen vectors, the evolution of different pollination systems has never been tested in any lineage of the genus. In this study, a group of endemic Greater Antillean passionflowers, with typical “hummingbird” flowers, were used to investigate the ecology and evolution of pollination systems. The internal transcribed spacer region and an unidentified single copy gene region were amplified and sequenced from a broad sampling of Caribbean and outgroup passionflower species. The resulting phylogenetic trees were used to map pollination system and characters such as corona-type. Field data on floral phenology, rates of nectar secretion, breeding systems and floral visitors were also collected from species representing the floral variation of the Greater Antillean taxa. Flowers showing typical “hummingbird” flowers were hummingbird-pollinated but the species studied differed in their breeding sytem. Also, although hummingbird-pollination appears to have evolved only once in the Greater Antillean passionflowers, these formed two sister lineages based on corona-type. Bat pollination evolved independently within one of these lineages.
1 - Saint Louis University, Department of Biology, 3507 Laclede Avenue, St. Louis, Missouri, 63103, USA
2 - University of Missouri-St. Louis,, Department of Biology,, 8001 Natural Bridge Road, St. Louis,, Missouri, 63121, USA
unidentified gene region.
Presentation Type: Paper
Location: Wasatch (Cliff Lodge)
Date: Monday, August 2nd, 2004
Time: 3:45 PM