The eency weency predator is in a group of animals called arthropods. That means they have natural joints in their spider legs and a hard outer skeleton (called an exoskeleton). The arthopods are then classified in a group of animals who are missing a backbone, invertebrates. So, spiders fall into a group of about 1.2 million known species (invertebrates) which make up more than 95% of all living animals.

Spider Anatomy

All spiders have fangs on each side of their mouths. The fangs are used to bite spider prey. Most spiders have venom producing glands in their heads. When the spiders bite and inject venom it usually paralyzes or kills the victim. Human spider bites are rarely fatal anymore if modern hospital treatment is available. The venom has powerful enzymes that break down body tissue into a liquid. That becomes food for the spider to suck up. Yum for the spider.

All spiders produce silk which is usually used in web making to capture insects or other prey. Orb webs are the most common spider webs. There are 2 kinds of spider silk: sticky silk, and fluffy silk. Sticky silk traps insects that are flying around. Fluffy silk tangles the legs of insects already caught in the web.

A spider myth (mis-information) is that all spiders weave webs. They don't, they hunt in other ways. Spitting spiders spit sticky silk (say that 3 times fast) at their prey to ensnare it, then they are able to bite it, inject venom and kill it for a tasty treat. Jumping spiders stalk, leap, and catch their prey.

Spiders have up to 8 eyes, but most have poor eyesight except the Jumping spiders and some others. So, they sense their prey by touch and vibrations through the ground or web.

Food and Mating

Spiders eat tons, I mean tons (over 350 million) of insects. That is said to be more than the weight of all humans on this earthly plane! So, they are all carnivores and super important insect predators. Without them, insects would increase and maybe some of those sci-fi insects take over the world thrillers would come true.

The mating can be dicey for the males. Females are larger than males in most spider species (possibly because they produce and carry many, many eggs), so the males are vulnerable and often get eaten instead of mated. The female produces a scent when it is ready to mate. The scent attracts males who are likewise wanting to mate. Here are 2 examples of different male spiders that know how to play the mating game without getting eaten.

The male crab spider (very small) ties the female with silk to calm her. It is not a strong enough tie to hold her but it makes the mating safe. The male orb-web spiders signal the females by a certain vibration on her web. She then knows not to attack and eat, but to mate instead.

Spider Enemies and Adaptions

Some bats, birds, fish, frogs, toads, and lizards are spider predators, but the most dangerous is other spiders or spiderkind (like mankind is mans worst enemy). Their worst enemy next to themselves is the wasp. Wasps are really mean to spiders. They don't neccesarily kill the eency weency victims, instead they sting, paralyze and drag the spider to their wasp nest. Then they leave the stiff spider as food for their larvae. Eaten alive so to speak! That's not all. Some wasps lay their eggs inside the spiders body so when the eggs hatch the hungry larvae eat the spider from the inside out. And you thought spiders were naughty!

Spiders have adapted defenses for survival. For instance, the largest spider, the tarantula has barb like fine, itchy hairs on it's body. The tarantula scrapes the hairs off so they get stuck in the enemy's face and eyes (if they have them). The predator then has a very itchy, uncomfortable feeling and gets warned away from the tarantula.

Another spider adaption is that of a bright color and spiky armor on the abdomen. This, too is a warning for the enemy not to eat it. Once an enemy has had the experience of eating a brightly colored spider and discovering it tastes bad, it will avoid brightly colored spiders in the future.  The color adaption works for the spider to catch prey also. One such spider has adapted a yellow color that matches yellow flowers where butterflys alight. Then it easily ensnares the unsuspecting butterfly.

Sea spiders have adapted to life on the sea shore. When the tide comes in they climb into a crack in a rock and spin a web over the entrance until the tide goes out. Dune spiders have adapted to live underground in deserts.

The eency weency predator cannot actually fly because it has no wings. However, it can seem like it is flying by ballooning. The spider lifts it's abdomen to push out a silk line. The wind picks it up and the spider goes ballooning. It is a survival technique when it's habitat is too crowded, or doesn't have enough food. The arial travelers have been known to balloon to heights over 14,000 feet, and 1,000 miles from land. No wonder there are more invertebrates than vertebrates.


photo credit - NASA                                                                                                   source credit - Spiders and Other Invertebrates by Andrew Solway