Contemporary sexual selection does not explain variation in male display traits among populations

Authors

J. Colton Watts, University of Nebraska-LincolnFollow
Allissa Flynn, University of Nebraska - LincolnFollow
Brigitte Tenhumberg, University of Nebraska - LincolnFollow
Eileen Hebets, University of Nebraska - LincolnFollow

Date of this Version

2019

Document Type

Article

Citation

Published in Evolution 73:9 (September 2019), pp. 1927–1940.

doi:10.1111/evo.13808

Comments

Copyright © 2019 by the authors. Evolution copyright © The Society for the Study of Evolution. Published by John Wiley Inc.

Abstract

Sexual selection is widely hypothesized to facilitate the evolution of reproductive isolation through divergence in sexual traits and sexual trait preferences among populations. However, direct evidence of divergent sexual selection causing intraspecific trait divergence remains limited. Using the wolf spider Schizocosa crassipes, we characterized patterns of female mate choice within and among geographic locations and related those patterns to geographic variation in male display traits to test whether divergent sexual selection caused by mate choice explains intraspecific trait variation. We found evidence of phenotypic selection on male behavior arising from female mate choice, but no evidence that selection varied among locations. Only those suites of morphological and behavioral traits that did not influence mate choice varied geographically. These results are inconsistent with ongoing divergent sexual selection underlying the observed intraspecific divergence in male display traits. These findings align with theory on the potentially restrictive conditions under which divergent sexual selection may persist, and suggest that long-term studies capable of detecting periodic or transient divergent sexual selection will be critical to rigorously assess the relative importance of divergent sexual selection in intraspecific trait divergence.