Meeting Abstract

49.1  Saturday, Jan. 5  The differential reproductive success of spider lineages is dictated by their ability to “outrun” their parasitic inquilines PRUITT, JN*; RIECHERT, SE; University of Pittsburgh; University of Tennessee

Understanding how the traits and actions of individuals unite to shape the collective behavior, life history, and performance of social groups is a long-standing goal of behavioral ecology. Here we report on the long-term effects of social group composition on colony-level life history and performance in the social spider Anelosimus studiosus (Araneae, Theridiidae). Anelosimus studiosus exhibit a notable behavioral polymorphism where colony members exhibit either an aggressive or docile behavioral type. We created colonies of three starting compositions (2 docile; 1 aggressive 1 docile; 2 aggressive) and tracked colony vitals of these colonies and their descendant colonies over the course of six years. We found that, relative to other phenotypic compositions, docile colonies sequestered inquilines at a faster rate than other compositions, grew more rapidly in size (# females therein), produced more descendant colonies per year, but suffered reduced longevity (i.e., not unlike the constellation of traits that define “r” and “K” life history strategies in solitary organisms). However, performance data on descendant colonies revealed that descendants of docile colonies tend to experience reduced survivorship, because upon the collapse of the parental colony, parasitic inquilines rapidly recruit to descendant colonies and drive their collapse. As a result, lineages founded by docile colonies are eradicated by rapid lineage selection, driven by the relative dispersal abilities of parasitic inquilines and their hosts.