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Alternative mating tactics are often expressed differentially based on a variety of factors associated with each mating context in order to maximize a male's reproductive success. In particular, males of many species attempt to reduce competition with males in the surrounding environment by altering their mating behaviors. In the wolf spider Rabidosa punctulata (Hentz, 1844) , males exhibit two distinct mating tactics: 1) courtship-comprised of visual and seismic signals or 2) direct mount-involving males grappling with females for copulation. In natural environments, these spiders are relatively dense. Competing males are often close by and could potentially intercept courtship displays, locate the nearby female and steal the copulation. Here we investigate whether males adjust their mating tactic expression in response to indirect and directly competing males, and whether these decisions affect their likelihood to copulate. In both experiments, the actions of a competing male did not affect the expression of any male mating behaviors in the other, suggesting a lack of an effect of scramble competition on tactic expression. Evidence from our triad mating experiment suggests a mating advantage for males that adopt the direct mount tactic when in direct competition with other males. In particular, direct mounts were most successful when multiple males were actively pursuing a female and when adopted first among the competitors. Additionally, we observed direct male mating interference whereby the copulating pair was broken up. Following these breakups, females were observed to mate multiply, often as a result of a direct mount. This new observation may provide a context in which males benefit through additional copulations by adopting the direct mount tactic. [ABSTRACT FROM AUTHOR]

Female mate choice decisions are often based on a variety of male characteristics, some of which may reflect male quality via condition-dependent trait expression. Here, we explore the condition dependence of a male secondary sexual trait in a wolf spider and examine its influence on female mate choice. In the wolf spider Schizocosa uetzi, mature males possess a multimodal courtship display (visual + seismic) in which they slowly raise and lower their dark colored forelegs. Foreleg color is highly variable among S. uetzi males with respect to both total amount and darkness. Using diet manipulations in conjunction with color quantifications, we demonstrate condition-dependent foreleg color. High-nutrient diet males had significantly higher body condition indices and possessed more and darker foreleg color than low-nutrient diet males. However, using multiple mate choice designs, we were unable to demonstrate a female preference for male foreleg color. Using both single and 2-choice mating designs as well as using females from a range of ages, we found that copulation success was consistently independent of male foreleg color. Instead, we found courtship intensity to be the only aspect of male courtship that influenced copulation success—males that copulated displayed more leg raises per second than those that did not copulate. [ABSTRACT FROM PUBLISHER]

Female preferences are frequently invoked to explain the widespread occurrence of elaborate male ornaments, yet empirical data demonstrating such preferences are sometimes equivocal or even contradictory. In the wolf spider Schizocosa stridulans, despite evidence of strong female choice, prior research has been unable to link the conspicuous sexually dimorphic foreleg ornamentation of males to their mating success. We conducted three experiments aimed at determining the function of this previously enigmatic ornamentation. Our first two experiments used males with phenotypically modified foreleg phenotypes in simple and complex mating environments in order to examine the relationship between the presence/absence of ornamentation and male mating success. In both experiments, we found no relationship: courtship rate was the sole predictor of mating success. In a third experiment, we used males with naturally varying foreleg ornamentation in mating trials. Ornamentation was subsequently quantified and we again examined the factors influencing male mating success. As in our first two experiments, we found courtship rate to be a good predictor of mating success. Additionally, we discovered that foreleg ornamentation and courtship rate interact to influence male mating success. At low courtship rates, males with more foreleg ornamentation have a mating advantage, whereas at high courtship rates, males with less foreleg ornamentation have a mating advantage. We discuss several potential explanations for these results. In summary, we provide the first evidence of a benefit of foreleg ornamentation in male S. stridulans and suggest that this benefit is realized by the interaction between ornamentation and courtship rate. [ABSTRACT FROM AUTHOR]