Papers in the Biological Sciences
Date of this Version
August 2007
Abstract
Sexual selection has long been recognized as a potential contributor to the divergence in reproductive characters that ultimately leads to speciation. Schizocosa ocreata and Schizocosa rovneri wolf spiders embody a classic example of species divergence resulting from such sexual selection, as they are reproductively isolated by courtship behavior alone. Here, we characterize a newly discovered population of wolf spiders in which brush-legged males (sensu S. ocreata) and non-ornamented males (sensu S. rovneri) are found syntopically. Mitochondrial sequence data (cytochrome oxidase subunit 1) indicate that the 2 male forms are not reciprocally monophyletic. We exposed subadult females from this mixed population to courtship advances from either brush-legged or non-ornamented males. Experienced females mated significantly more with brush-legged males, whereas inexperienced females showed no mating distinction. In essence, we demonstrate that females from this population will differentially choose between males of 2 distinct forms based on prior experience. Specifically, experience leads to a preference for brush-legged males. We also show that brush-legged males are more sexually aggressive than non-ornamented males. This study highlights the importance of prior experience on subsequent mate choice and has potential implications regarding the extent to which experience can influence polymorphism maintenance and/or species divergence and the evolution of secondary sexual traits. Key words: mate choice, plasticity, polymorphism, sexual aggression, speciation, subadult experience.
Comments
Published in Behav Ecol 18:1010–1020 (2007). Copyright © The Author 2007. Used by permission.