Repeatability but no short‐term plasticity in the web architecture of Latrodectus hesperus western black widow spiders (Araneae: Theridiidae).

A spider's web is an extended phenotype and a direct product of behavior. Variation in web architecture may be the result of individual differences in genotype, environment, or experience. We analyzed variation in the web architecture of western black widow spiders, Latrodectus hesperus, by testing two hypotheses: (a) intrinsic individual differences and (b) plasticity according to experience of the site of prey capture. We used treatments manipulating the site of prey capture experienced by the spiders: sheet only, gum‐footed lines only, and alternating patterns between sheet and gum‐footed lines equally. We found considerable consistent individual variation (repeatability of r =.56) in one web component (gum‐footed lines) and negligible plasticity in either component. We discuss our results in terms of the potential for the design of these web components to respond to selection, and of potential additional causes of variation in extended phenotypes. [ABSTRACT FROM AUTHOR]