Tactical adjustment of signalling leads to increased mating success and survival

Abstract

Most sexually reproducing animals overcome the challenge of searching for and attracting mates by utilizing signals that are broadcast through a spatially and temporally varying environment. A diverse suite of behavioural solutions exist for overcoming such environmental variability, including the adjustment of signalling behaviour based upon receiver feedback. Few studies have directly examined the relationship between such tactical signalling adjustments and proxies of male fitness; the few that have, failed to find a relationship. Using the wolf spider, Schizocosa rovneri, we set out to first quantify among-male variation in the form and degree of responsiveness to female feedback. Following exposure to female receptivity cues, some males increased their signalling on an effective signalling substrate (filter paper) while others decreased signalling on the effective substrate. These groups of males were then run through mating trials, conducted in a heterogeneous environment, to examine the relationship between male signalling adjustments and subsequent mating success. Males that adaptively adjusted their signalling (i.e. increased signalling on a more effective substrate) were (1) more likely to copulate, (2) achieved a copulation more quickly and (3) were less likely to be attacked; thus establishing a positive relationship between tactical adjustments of courtship signalling and male fitness.