Presentation Detail

Selection, Sexual

Symes, Laurel [1].

Species composition affects the shape of female response functions.

For many populations,the costs of responding to or mating with co-occurring heterospecifics can be a major source of selection on mating preferences. Interference from heterospecifics is often predicted to result in preferences where females are most responsive to the mean conspecific trait and are less responsive to traits that differ from this value. However, when the male trait distribution is not bounded by heterospecifics in one direction, females with preferences for extreme traits in the unbounded direction would have a high probability of obtaining a conspecific mate. Consequently, the shape of the preference may depend on the unique context that favored the evolution of the preference. To determine how community composition affects the evolution of female mating preferences, I investigated mating responses of Oecanthus tree crickets, a diverse genus where it is common to find multiple species signaling simultaneously. I focused on female responses to male pulse rate to determine what range of pulse rates were capable of eliciting female response and how the range of acceptable pulse rates varied depending on community composition. To test how the presence of heterospecifics affected the shape of female response functions, I constructed response functions for species that had the slowest and fastest pulse rates in their community as well as species that had a pulse rate that was intermediate within the community. The species with the fastest pulse rates in the community consistently showed the greatest response to pulse rates that were faster than those produced by their males, while the intermediate pulse rate species showed strong response to the pulse rate produced by their males and dramatically decreased response to pulse rates that deviated slower or faster. These results suggest that species composition plays an important role in shaping female responses to signals. By understanding how signals function within a community,we may gain a deeper understanding of whether certain species are pre-adapted to invade a community and how extinction and changes in abundance affect the signal evolution of other species in the community. The findings of this work may provide novel insight for predicting the frequency and directionality of hybridization.

1 - Dartmouth College, Biology, 78 College St, Hanover, NH, 03755, United States

Keywords:
mate recognition
species interactions
female preference.

Presentation Type: Regular Oral Presentation
Session: 40
Location: Cotton A/Snowbird Center
Date: Saturday, June 22nd, 2013
Time: 4:00 PM
Number: 40003
Abstract ID:775
Candidate for Awards:W.D. Hamilton Award for Outstanding Student Presentation