Metabolic responses to predation risk in a jumping spider

Predators not only consume prey but also modify the traits of prey (e.g. physiology and behaviour). This study examined how the metabolic rate of prey (measured by CO 2 release) changes as they perceive the presence of a predator in a laboratory setting. The jumping spider H asarius adansoni was used as the study subject. Two species of jumping spiders, P lexippus paykulli and P tocasius strupifer , and the oriental fruit fly B actocera dorsalis were used as visual cues. P l. paykulli is larger than H . adansoni and was used as a cue of predators. P t. strupifer (smaller than H . adansoni ) and B . dorsalis were used as reference controls. The response of H . adansoni to P l. paykulli was dynamic, with CO 2 release first increasing with the detection of the predator and then decreasing to a low level. Similar responses were not observed when H . adansoni detected the other species. The results show that H . adansoni reacts to visual cues of predation threat by rapidly changing its metabolic rate and suggest that the dynamic expressions of metabolism contain rich information about how H . adansoni perceives the environment.