Abstract Detail

Ecological Section

Dorken, Marcel [1], Van Drunen, Wendy [2].

Wind pollination promotes spatial segregation of the sexes.

Spatial segregation of the sexes (SSS) has evolved independently in at least 38 plant families. Convergent evolution of SSS suggests there are benefits to segregation and empirical evidence has demonstrated growth advantages to segregated plants. However, the separation of plants from their mating partners should reduce their reproductive fitness and how increased performance might be offset by mating costs of SSS has received little attention. Using a phylogenetically controlled comparative approach we confirm previous assertions that SSS should be associated with wind pollination. To investigate the mating costs of SSS, we used spatially explicit stochastic simulations to examine whether mating costs are equal for females vs. males. We show that male fitness is more strongly affected by segregation than female fitness under a range of assumptions of the magnitude of segregation, the shape of pollen dispersal curves, and the relative performance of segregated vs. unsegregated plants. However, features that promote the evolution of dioecy (e.g., greater pollen dispersal distances) also eliminate the mating costs of SSS to males. Because wind pollination is often associated with greater pollen dispersal distances it might also promote the evolution of SSS by reducing the mating costs of segregation to males.

Broader Impacts:

1 - Trent University, Biology, 1600 West Bank Drive, Peterborough, ON, K9J 7B8, Canada
2 - Trent University, Department of Biology, 1600 West Bank Drive, Peterborough, ON, K9J 7B8, Canada

Keywords:
comparative analysis
dioecy
sexual dimorphism
stochastic simulation
wind pollination.

Presentation Type: Oral Paper:Papers for Sections
Session: 28
Location: Marlborough B/Riverside Hilton
Date: Tuesday, July 30th, 2013
Time: 10:30 AM
Number: 28002
Abstract ID:128
Candidate for Awards:None