Systematics Section / ASPT
Jones, Eric .
How many times, and in what evolutionary contexts, did heterostyly arise in the angiosperms?
IN heterostylous plants, a genetic polymorphism produces two or three floral types (morphs) among individuals of a population. The floral morphs have their anthers and stigma positioned reciprocally, and often a physiological incompatibility system makes inter-morph crosses more successful than intra-morph crosses. The number of families in which heterostyly occurs is often cited (28 families and 155 genera) yet the number of independent origins of heterostyly across angiosperms has not been elucidated. I gathered all publicly available DNA sequence data on those families, inferred their phylogenies, inferred the number of gains and losses of heterostyly in each family in a parsimony framework, and inferred the optimal rates of gain and loss in a likelihood framework. There was significant variation in available data across the heterostylous families, with 300+ OTUs available for some families (Primulaceae and Rubiaceae) and few OTUs available for others (e.g., Conaraceae and Linaceae) I will discuss the way that our understandings of the familiesí phylogenetic relationships have changed since the last consideration of the evolutionary context for the origins of heterostyly, and how this changes our views on correlates to the origins of heterostyly, such as may be found in habitat type, pollination characteristics, and floral shape. I will also discuss the sensitivity of the results to the current taxonomic sampling.
Log in to add this item to your schedule
1 - Florida State University, Department of Biological Sciences, Tallahasse, Florida, 32306-1100, USA
Presentation Type: Oral Paper:Papers for Sections
Location: 144/Performing Arts Center
Date: Monday, July 31st, 2006
Time: 4:30 PM