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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2009.04.012 Byline: Chad D. Hoefler (a), Allison L. Carlascio (a), Matthew H. Persons (b), Ann L. Rypstra (a) Abstract: Indirect benefits derived by females that mate with males that express preferred traits are important to our understanding of 'good genes' models of sexual selection. However, few studies have explored male courtship behaviours with potential indirect benefits conferred to females in order to ascertain whether these behaviours serve as honest indicators of male quality. Using a common species of wolf spider, Pardosa milvina, we addressed the honesty of male courtship behaviours in two laboratory experiments. In our first experiment, we quantified the repeatability of courtship rate in adult males that were manipulated to be in high or low condition and were sequentially presented with adult virgin females that similarly differed in body condition. In our second experiment, we explored the effect of male courtship rate on several measures of fitness: number of offspring produced, days until offspring emerged and offspring viability measured as offspring survival. Our experiments show that male courtship rate is statistically significantly repeatable except when males in high condition have repeated encounters with females in low condition. Our results also reveal that females have the potential to gain indirect genetic benefits by mating with males that naturally court at high rates: females produced more offspring that emerged from eggsacs sooner and survived starvation better compared to females that mated with males that naturally courted at low rates. Our study provides additional support that male courtship rate is an honest indicator of quality, and it makes the novel finding that the repeatability of courtship rate is context sensitive. Author Affiliation: (a) Center for Animal Behavior and Department of Zoology, Miami University, Oxford, OH, U.S.A. (b) Department of Biology, Susquehanna University, Selinsgrove, PA, U.S.A. Article History: Received 8 January 2009; Revised 2 March 2009; Accepted 27 March 2009 Article Note: (miscellaneous) MS. number: A09-00013

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2008.12.026 Byline: Ann L. Rypstra (a)(b), Ann M. Schlosser (c)(d), Patrick L. Sutton (c)(d), Matthew H. Persons (e) Abstract: Many animal signals, especially those important to finding and attracting mates, are multimodal, which means they involve two or more sensory modalities. Among other sensory modalities, the wolf spider, Pardosa milvina (Araneae, Lycosidae), uses a variety of chemical and visual information in reproductive activities. Here we report the results of four laboratory experiments in which we explored the effects of visual and chemical information on the behaviour of males. First we established that chemical cues enabled males to find females and that visual cues kept the males' attention focused in the area of the females. Subsequently, we examined the separate and combined effects of visual and chemical cues on the interactions between males competing for virgin or mated females. The behaviour of interacting males revealed that either chemical or visual information was sufficient for them to discriminate between mated and virgin females. Chemical cues elicited more courtship activity and more intense aggressive interactions between males than visual cues. When males were able to see live mated females but were in contact with chemical cues from virgins, aggression was lower and, conversely, when males were able to see live virgin females but were in contact with chemical cues from mated females, aggression increased. We conclude that chemical cues provided males with the most critical discriminatory information. Although the two types of signals are largely redundant, there are some circumstances where they enhance the response of the males and there is an intersignal interaction that allows males to adjust their behaviour when presented with a receptive female. Author Affiliation: (a) Center for Animal Behavior, Miami University, Hamilton, OH, U.S.A. (b) Department of Zoology, Miami University, Hamilton, OH, U.S.A. (c) Center for Animal Behavior, Miami University, Oxford, OH, U.S.A. (d) Department of Zoology, Miami University, Oxford, OH, U.S.A. (e) Department of Biology, Susquehanna University, Selinsgrove, PA, U.S.A. Article History: Received 21 July 2008; Revised 22 September 2008; Accepted 18 December 2008 Article Note: (miscellaneous) MS. number: A08-00477

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2003.12.030 Byline: Matthew H. Persons, George W. Uetz Abstract: Sexual cannibalism may influence expression of elaborate male traits by either reinforcing or opposing sexual selection. Male Schizocosa ocreata (Hentz) wolf spiders (Lycosidae) have tufts of bristles on the first pair of legs that may function as a condition-indicating signal trait. We paired virgin and previously mated adult females with males under seminatural conditions (laboratory containers with leaf litter). For males encountering virgin females, probability of attempted premating cannibalism varied with male size, body condition, tuft size, fluctuating asymmetry of tufts (FA) and female size (larger females attacked smaller males and males in poor condition with smaller, more asymmetrical tufts). Probability of successful cannibalism varied with the relative size of both sexes and female body condition, but not male tuft size (smaller males were cannibalized by larger females in better condition). Males with larger tufts (relative to body size) were more likely to mate, but no other traits (male or female) were associated with mating success. Postmating cannibalism risk was associated with female size and age, and male size, body condition and tuft size (larger, older females cannibalized smaller males in poor condition with smaller tufts). For males paired with previously mated females, probability of cannibalism was influenced by size of both sexes and male tuft size (larger females cannibalized smaller males with smaller tufts). While no morphological characteristics (male or female) influenced the probability of second matings, recently matured females were more likely to mate twice. Results suggest that both mate choice and sexual cannibalism can impose reinforcing directional selection on male size and secondary sexual characters. Author Affiliation: Department of Biological Sciences, University of Cincinnati, U.S.A. Article History: Received 29 January 2003; Revised 21 May 2003; Accepted 19 December 2003 Article Note: (miscellaneous) MS. number: A9539R

Sensory cues devoid of food reward strongly influence patch residence time in wolf spiders. Spiders spend more time in patches with visual cues alone or both visual and vibratory cues as compared to those with only vibratory information. The behavior of 60 mature females of the common wolf spider, Schizocosa ocreata, are studied in a four-chambered artificial foraging patch. The spiders can move freely from chamber to chamber and change patch residence time using visual cues that do not involve sampling or prior experience.

Understanding the decisions that animals make in the presence of predation risk can reveal their assessment of current and future reproductive options. The wolf spider, Pardosa milvina, has a conspicuous courtship display that is an indicator of male quality. In an initial experiment, we determined that male courtship was highly repeatable and correlated with symmetry. We then used symmetry as an indicator of quality to explore the reactions of males when presented with simulated predation risk and an attractive virgin female. There were no differences in courtship features between risk and no risk treatments unless we took into account male quality. High-quality males reduced courtship intensity under risk conditions suggesting that they estimated their long-term fitness prospects as strong. This response is consistent with the asset protection principle, which suggests that animals with high value traits should behave cautiously. Low-quality males courted at high levels under predation risk, which seemed to be reckless attempts to attract females. This response is analogous to the "desperado effect," which is one explanation for vigorous fighting by inferior animals in contests. Although females used behavior to select males when no predator information was present, they seemed to use symmetry in the presence of predator cues. The ability of females to select the most attractive males suggests that they can accurately assess male quality under laboratory conditions. High courting "desperado" males may occasionally be selected in more complex environments and/or when they are in competition with other males. [ABSTRACT FROM AUTHOR]

Females of many spider species invest in chemical advertisements to attract males, yet variation in investment relative to the presence or quality of males remains poorly understood. Males of the wolf spider Pardosa milvina court females longer and more intensively when in contact with female silk and also court more intensively when encountering silk from virgin rather than mated females; therefore, females may use silk as a medium to advertise their receptivity to mate. We estimated female investment in advertisements by measuring variation in the quantity and type of silk deposited by females in the presence or absence of males and among males that varied in their courtship intensity. We measured dragline silk, cord silk, and attachment disk deposition from females on gridded sheets of paper in response to four stimuli over a 30-min period (n = 39/treatment): (1) an intensively (high) courting male with access to female silk, (2) a weakly courting or non-courting male (low) without access to female silk, (3) no male present, but female silk present (silk control), and (4) no stimulus present (control). Females produced significantly more dragline silk and significantly less cord silk in the presence of low-courting males compared to any other treatment, but we found no difference in attachment disk deposition across treatments. Our results suggest that females invest more heavily in dragline deposition when encountering low-courting males. Additional studies are necessary to determine the relative role of different silk types in male-female sexual communication. [ABSTRACT FROM AUTHOR]