Linking consistent individual differences in web structure and behavior in black widow spiders

Abstract

Individuals may vary consistently in their architectural makeup of the constructions they build, which might have tremendous implications for their ecology and fitness. In particular, the relationship between individual differences in architectural constructions and behavior (i.e., animal personalities) is largely unexplored. Individual black widow spiders, Latrodectus hesperus, build a 3D cobweb made up of distinctive components serving to support foraging (gumfooted lines) or antipredator protection (structural lines). To explore the relationship between individual differences in behavior and architectural constructions, we quantified 1) the level of consistent individual variation in several elements of web structure and 2) the level of consistent individual variation in foraging behavior and its relationship with web structure. We controlled for condition-dependent or environmental effects by satiating all spiders prior to assays and maintaining them in standardized conditions. Spiders exhibited consistent differences in the number of gumfooted lines they built for capturing preys and overall web weight, but not in the number of structural lines. Individuals also varied consistently in their tendency to attack a prey cue, despite all spiders being satiated. Finally, spiders producing more gumfooted lines exhibited a higher tendency to attack the prey cue. Our results suggest that the architectural constructions may impact the expression of individual behavioral differences (or animal personalities) and suggest that individual behavior and extended phenotype may be part of alternative foraging strategies in L. hesperus.