Jumping spider family (Salticidae) is the largest family of spiders with 13% of all the species. It has more than 500 described genera and about 5,000 described species. Jumping spiders have the best vision and they use it to navigate and hunt. They are capable of jumping place to place, secured by a silk tether. Both their book lungs and the tracheal system are well-developed, as they depend on both systems (bimodal breathing). They are often recognized by their eye pattern. All jumping spiders have four pairs of eyes including two big anterior median eyes.
Jumping spiders live in many places. Most species are found in tropical areas. They are also found in forests, scrub lands, deserts, intertidal zones, tree barks and even mountains.
Jumping spiders have very good vision. The anterior median eyes are main vision system. A focused image is created on the retina with the help of these eyes. Four different kinds of receptor cells are layered in the anterior median eyes. It enables them to have tetrachromatic color vision up to ultraviolet range. Their color receptors are highly sensitive.
Although their principle anterior median eyes have high resolution but their field of vision is very narrow (from 2 to 5 degree). They can use their eyes to watch various targets at once, and such behavior can be seen from the outside. When they are looking straight at you, their eyes color change in black.
Particles in the retina can be seen in the left eye.
Jumping spiders are generally active hunters. Well-developed internal hydraulic system of jumping spiders gives them flexibility. This enables them to jump without having large muscular legs. By a single jump they can cover distance several times of their body. When they jump from place to place, they tether 'a filament of silk'. Even if they miss the target, they can start over again. The most interesting part is they can learn, recognize, and remember colors.
Unlike other spiders jumping spiders are active hunters. They don't rely on their webs to feed themselves. Instead they go out and hunt for themselves. They use their excellent vision system to identify and track the target and eventually making it as their prey. Once they catch the target, they inject venom with their fang, and venom starts working very quickly giving the victim a little time to react. The genus Portia follows both conventional and unconventional tactics to hunt. They can stalk prey from a great distance making it impossible for their prey to identify the predators.