I smell a femme fatale: Can male wolf spiders chemically detect a cannibalistic prospective mate?
Virgin female Hogna helluo wolf spiders cannibalize prospective mates in 13-20% of encounters with courting males. Males may therefore benefit by possessing the ability to detect and avoid cannibalistic females. We tested if prior cannibalistic experience alters female behavior toward males and if males can detect cannibalistic females based on either direct interactions with females or indirectly through cues from female silk and excreta. We reared 36 female spiders on entomophagic diets consisting of house crickets (Acheta domesticus) and an additional 34 females on araneophagic diets consisting of two Hogna feedings at adulthood prior to testing. We then measured male and female mating behavior across the following treatments (14-20 replicates/treatment): 1) cannibalistic female on cannibalistic chemical cues, 2) cannibalistic female on non-cannibalistic chemical cues, 3) non-cannibalistic female on non-cannibalistic chemical cues, and 4) non-cannibalistic female on cannibalistic chemical cues. Male Hogna were placed with females and cannibalism events, courtship duration, courtship latency, mating success, and courtship intensity were recorded. Males significantly decreased courtship duration in the presence of cannibalistic females and significantly increased courtship intensity when encountering silk from females that had cannibalized previously. Cannibalistic females showed higher numbers of leg taps, a putative receptive response, toward males than non-cannibals but we found no significant difference in mating success or cannibalism frequency across treatments. Results suggest that males discriminate between females who have eaten conspecifics and those who have not based on information in silk, but female cannibalism frequency and male mating success is unrelated to recent female cannibalism experiences.
