Papers in the Biological Sciences


Date of this Version

August 2005


Published in Behav Ecol 16:981–988 (2005). Copyright © The Author 2005. Used by permission.


Sexual selection is thought to have driven the diversification of courtship behavior and associated ornamentation between geographically isolated populations of the jumping spider Habronattus pugillis Griswold. In an attempt to understand the pathways of sexual selection during this diversification, we conducted reciprocal mating trials between two populations of H. pugillis (Santa Rita [SR] and Atascosa [AT]) that differ in both male courtship display and secondary sexual ornamentation. Observations of mating frequencies show a xenophilic mating preference in which SR females have a stronger response to AT males than to SR males, while AT females show no difference in mating frequency. These results are not consistent with a coevolutionary process in which male traits and female preferences evolve in concert, positively reinforcing each other. We discuss alternative pathways of sexual selection that may have acted in this system, including the possibility that female preferences and male traits have evolved antagonistically. In addition, we found that SR females spent a higher proportion of time prior to copulation visually attentive to AT males versus SR males. This difference in visual attention prior to copulation was not seen in AT females and may provide insights into our observations of xenophilic mating preference. Key words: antagonistic coevolution, attention, diversification, jumping spiders, sexual selection, speciation.