Widespread army ant aversion among East African jumping spiders (Salticidae).

Jumping spiders (Salticidae) typically prey on a variety of arthropods of similar size to themselves, but rarely on ants. Using 28 salticid species from East Africa, we frst investigated vision-based aversion to ants by recording latency to enter a transparent sealed chamber fanked by chambers containing living army ants (Dorylus sp.) or tsetse fies (Glossina pallidipes) of comparable size. For all species, entry latency was signifcantly longer when the stimuli were ants. In another experiment, we used dead ants and tsetse fies mounted in a life-like posture as stimuli; except for Goleba puella, a species with unusual retinal ultrastructure, we again found signifcantly longer entry latency when the stimuli were ants. Our fndings imply that these salticids express an aversion specifcally to ants even when restricted to using vision alone and, except for G. puella, even when relying on solely the static appearance of the insects. Having used salticids from laboratory cultures with no prior experience with ants, our fndings are consistent with vision-based aversion to army ants being innate