Meeting Abstract

18-6   10:45 - 11:00  Exploitation of anti-predator behavior in the courtship displays of Maratus jumping spiders. Harris, OK*; Congelli, MF; Morehouse, NI; University of Cincinnati; University of Cincinnati; University of Cincinnati harrisok@mail.uc.edu https://homepages.uc.edu/~morehonn/olivia-harris/

Males often exploit female sensory biases during courtship, most commonly by mimicking food or exploiting neophilic responses. However, one unexplored possibility is the exploitation of female anti-predatory responses. The jumping spider genus Maratus presents an intriguing possibility of this fear-based strategy. Some Maratus species exhibit patterning that to the human eye resembles the faces of jumping spider predators, such as wasps and mantids. Males might benefit from predator mimicry by inducing the female to freeze, a common anti-predator response in spiders. This would reduce the risk of sexual cannibalism, and allow the male to approach the female more easily. We hypothesized that some Maratus species have evolved predator-mimicking abdominal fan displays to influence female behavior early in courtship. We used computer-vision-based machine learning to investigate the likelihood of viewer confusion between male displays and common predator faces. We collected images of the displays of 63 Maratus species, and the faces of co-occurring predators (mantids and wasps) and prey (various flies). A multiclass, linear, support-vector machine classified images based on visual features extracted via computer vision. The latter modeled responses of female Maratus principal (high resolution and color vision) and secondary eyes (low resolution and achromatic) viewing stimuli at multiple distances. We find that 12 Maratus species are never misclassified, whereas a separate 12 species are misclassified as predators at least 20% of the time. We also find significant roles for viewing distance and color information in misclassification of Maratus fans. These results suggest that sensory exploitation via predator mimicry may occur across the genus Maratus, and may have evolved more than once. This work demonstrates the role the ‘ecology of fear’ may play in courtship evolution.