in humans, and is six times better than in the most acute insect eye. It is also clearer in daylight than a cat's vision. P. africana relies on visual features of general morphology and colour (or relative brightness) when identifying prey types. P. schultzi′s hunting is stimulated only by vision, and prey close by but hidden causes no response. P. fimbriata use visual cues to distinguish members of the same species from other salticids. Cross and Jackson (2014) suggest that P. africana is capable of mentally rotating visual objects held in its working memory. However, a Portia takes a relatively long time to see objects, possibly because getting a good image out of such small eyes is a complex process and requires a lot of scanning. This makes a Portia vulnerable to much larger predators such as birds, frogs and mantises, which a Portia often cannot identify because of the predator's size. Movement When not hunting for prey or a mate, Portia species adopt a special posture, called the "cryptic rest posture", pulling their legs in close to the body and their palps back beside the chelicerae ("jaws"), which obscures the outlines of these appendages. When walking, most Portia species have a slow, "choppy" gait that preserves their concealment: pausing often and at irregular intervals; waving their legs continuously and their palps jerkily up and down; moving each appendage out of time with the others; and continuously varying the speed and timing. When disturbed, some Portia species are known to leap upwards about often from the cryptic rest pose, and often over a wide trajectory. Usually the spider then either freezes or runs about and then freezes. Reproduction Portia exhibits a mating behavior and strategy different from that of other jumping spiders. In most jumping spiders, males mount females to mate. The Portia male shows off his legs and extends them stiffly and shakes them to attract the female. The female then drums on the web. After the male mounts her, the female drops a dragline and they mate in mid-air. Mating with Portia spiders can occur off or on the web. The spider also practices cannibalism before and after copulation. The female usually twists and lunges at the mounted male. (P. fimbriata, however, is an exception; it does not usually exhibit such behavior.) If the male is killed before completing copulation, the male sperm is removed and the male