Color vision improves foraging success and accelerates reproduction in a jumping spider.

Color vision is thought to convey fitness advantages during foraging, but empirical tests of this idea are exceedingly rare. We manipulated prey color cues in tests with the trichromatic jumping spider Habronattus pyrrithrix to assess whether their ability to use their color vision affected foraging success and reproduction. Mated adult female spiders were first trained to associate the color red with experimentally manipulated unpalatable (bitter) prey and then tested to confirm that they learned this association (independent of brightness cues). They were then divided into 2 treatment groups. Both groups were given a similar foraging task where they foraged among arrays of palatable and unpalatable prey. One group was given red color cues to make these choices (as in training, red signaled unpalatability, independent of brightness), while the other group did not have red color cues to make these choices. Spiders with access to color cues targeted the palatable prey more accurately, consumed more palatable prey during their trial period, and tended to direct fewer wasted attacks toward unpalatable prey. Over a 2-mo period, females with consistent access to color cues laid eggs earlier and tended to be heavier, but the total number of egg sacs, eggs, and hatchlings produced was unaffected. This study is among the first to directly link color vision with foraging success and fitness in any animal. Future work should track total lifetime reproductive output, test benefits of color vision across ecological contexts, and explore fitness consequences across the salticid phylogeny.