Bringing down the house: male widow spiders reduce the webs of aggressive females more
Theory suggests that males should adjust courtship in response to a variety of factors, including female quality, the risk of male-male competition, and often in spiders, the risk of sexual cannibalism. Male black widow spiders demonstrate a behavior during courtship whereby they tear down and bundle a female’s web in addition to providing other vibratory and contact sexual signals. This web reduction has been hypothesized to play a role in all three factors (sexual signaling, competition reduction, and cannibalism reduction), but rarely are these tested together. Here, we test these hypotheses by conducting mating trials using the western black widow (Latrodectus hesperus) and measuring both male and female quality and behavior. Our results indicate that amount of web reduction is best predicted by female aggression, and not aspects of either male or female quality (e.g., body mass), or by the potential for the web to attract other males (e.g., web mass). Yet, actual mating success was best predicted by the proportion of web reduced. Furthermore, there was no consistent among-individual variation in either reduction behavior or male success, indicating that all variation in both measures was due to plasticity and/or other unaccounted-for male or female traits. Collectively, we conclude that the primary function of web reduction behavior is to reduce female aggression and thus the risk of sexual cannibalism, and that any other functions such as signaling and reducing male-male competition have relatively lower importance.
Male widow spiders must account for female aggression, quality, and male-male competition when courting females. During courtship, males will reduce a female’s web by tearing it down and bundling the silk, which may aid in all three of these issues. Our results demonstrate that males reduce the webs of aggressive females more, and less so to potentially reduce competition from other males or in response to female quality. Ultimate mating success was dictated by how much a male reduced the web of a given female. Finally, males showed no among-individual variation in reduction behavior, indicating that the extensive variation in this behavior is due solely to plasticity in response to the female.
KeywordsCourtship behavior Web reduction Sexual cannibalism Mate choice Latrodectus
Thanks to Cameron Jones for comments on an early version of this manuscript.
ND and AD designed the study. ND conducted the experiment and data processing in conjunction with CB and CS. ND conducted the statistical analysis, and wrote the initial draft of the manuscript. All authors contributed to the final editing of the manuscript.
Funding was provided by a University of Arizona Postdoctoral Excellence in Research and Teaching Fellowship (NIH # 5K12GM000708-17) awarded to ND and by the NSF (grant no. IOS-1455983 to AD).
Compliance with ethical standards
Conflict of interest
Widow spiders are not subject to any ethical protocals in the United States.
- Anava A, Lubin Y (1993) Presence of gender cues in the web of a widow spider, Latrodectus revivensis, and a description of courtship behaviour. Bull Br Arachnol Soc 9:119–122Google Scholar
- Bartoń K (2013) MuMIn: multi-model inference. R package version 1.9. The Comprehensive R Archive Network (CRAN), Vienna, p 13Google Scholar
- Bates D, Maechler M, Bolker B, Walker S (2013) lme4: Linear mixed-effects models using Eigen and S4. R package version 1Google Scholar
- Breene RG, Sweet MH (1985) Evidence of insemination of multiple females by the male black widow spider, Latrodectus mactans (Araneae, Theridiidae). J Arachnol:331–335Google Scholar
- Burnham K, Anderson D (2002) Model selection and multimodel inference: a practical information-theoretic approach. SpringerGoogle Scholar
- DiRienzo N, Bradley CT, Smith CA, Dornhaus A (2018) Data From: Bringing down the house: male widow spiders reduce the webs of aggressive females more. Behav Ecol Socibiol. https://doi.org/10.5061/dryad.tp7637c
- Lubin YD (1986) Courtship and alternative mating tactics in a social spider. J Arachnol:239–257Google Scholar
- Montiglio P-O, DiRienzo N (2016) There’s no place like home: the contribution of direct and extended phenotypes on the expression of spider aggressiveness. Behav Ecol:arw094Google Scholar
- Nakagawa S, Schielzeth H (2010) Repeatability for Gaussian and non-Gaussian data: a practical guide for biologists. Biol Rev 85:935–956Google Scholar
- R Core Team (2015) R: a language and environment for statistical computing. In. Available from CRAN sitesGoogle Scholar
- Ross K, Smith RL (1979) Aspects of the courtship behavior of the black widow spider, Latrodectus hesperus (Araneae: Theridiidae), with evidence for the existence of a contact sex pheromone. J Arachnol:69–77Google Scholar
- Schielzeth H, Nakagawa S (2011) rptR: repeatability for Gaussian and non-Gaussian data. R package version 0.6 404:r36Google Scholar
- Scott C, Gerak C, McCann S, Gries G (2017) The role of silk in courtship and chemical communication of the false widow spider, Steatoda grossa (Araneae: Theridiidae). Ethology:1–7Google Scholar
- Van Helsdingen P (1965) Sexual behaviour of Lepthyphantes leprosus (Ohlert)(Araneida, Linyphiidae), with notes on the function of the genital organs. Zoologische Mededelingen 41:15–42Google Scholar