Jumping spiders are one of Mother Nature’s rather magical creations. A fascinating creature and completely harmless to humans, the jumping spider is actually quite small, growing only about five to 10 millimeters.
The family of jumping spiders (Salticidae) is the largest of spider families, having about 5000 different species. These arachnids live in many different habitats and therefore have many different adaptations to help them survive.
Although they are named ‘jumping spiders’ their jump is not really as high as we might expect. Their strongest feature instead is their extremely good vision.
All spiders have four pairs of eyes, as do the jumping spiders. However, their front and center pairs are especially larger than the rest, and this gives them an almost “puppy dog” look.
Their vision is often compared to the function of a zoom lens in a camera. They can alter their vision depending on the situation. The main function of the other six eyes (3 pairs) is it gives them added focus and visual clarity, which is an asset when need to identify, and strike at their prey.
The jumping spider also has long front legs. However, they jump from their legs, while using the long front ones to hold prey.
Their lack of strong back legs that would have ideally propelled them forward when they are jumping is made up for by an excellent internal hydraulic system, which extends their limbs by changing the body fluid pressure within them.
An interesting phenomenon that occurs when the jumping spider jumps is that he leaves a little silk strand (dragline) of his web anchored to the place from where he jumped. This leads him back to where he started.
Their webs or “pup tents” have many purposes. They build these for shelter from bad weather, to sleep, to store egg cases, and to protect themselves during the winter.
Some jumping spiders have also adapted to the varied environment around them by learning, recognizing and remembering colors so that they can adapt their hunting to them.
Speaking of hunting, these clever arachnoids are considered seasoned hunters; they stalk and kill their prey, instead of depending on their elaborate web to catch an unsuspecting insect. They pounce on their victim and immediately leave a poisonous bite, which kills the insect instantly.
His dragline also allows him to drop down into areas which otherwise would have been gravitationally impossible to reach, catch his prey, and then come back to his original position.
Their courtship and mating rituals further serve evolutionary functions. The males, who look quite different to the females, are colorful and have iridescent furs, which they display in a courtship “dance”. If the female is receptive, she indicates it by getting into a crouching position, the male then extends his front legs towards her, and if she continues to show her liking, he climbs onto her back and inseminates her.