Spiders are not miniature vampires; all species, as far as we know, digest some solid parts of their prey. What makes it especially interesting is that the digestion process begins outside the spider, where anyone who wants to look can see how it works. Put a medium-sized insect in the web of a large orbweaving spider in the garden. You will see the spider bite the prey, wrap it in silk, wait for it to die, then begin to eat. As a first step in eating, the spider will literally vomit digestive fluid over the prey.
Then the prey is chewed with the "jaws" chelicerae , and the fluid is sucked back into the mouth together with some liquefied "meat" from the prey. The spider repeats this process as often as necessary to digest, and ingest, all but the inedible hard parts. What is discarded afterwards is a small ball of residue. Spiders other than orbweavers may eat the prey's body but discard some of the wings, legs, etc.
Spiders with very small if strong jaws such as crab spiders and cobweb weavers make small holes in the prey and vomit their digestive fluid into the prey's body, the end result being a hollow shell with some or most of the muscles and internal organs digested and sucked out. Spider Myths. Small rove beetles like Stenus comma below fly well and are sometimes caught by orbweavers like Araneus diadematus preparing to eat a different beetle below ; the much smaller remains of a rove beetle of the same size and shape show the results of external digestion!
Other species, including crab spiders and wolf spiders, are stealth hunters that actively seek out their prey as they move around. Some spider species spice up their meat-heavy diets with vegetarian meals from different plant types.
The menu can include nectar, plant sap, honeydew, leaf tissue, pollen, and seeds. While most spiders have eight eyes, there are some that only have six, and even some spiders that have fewer than six eyes. They always come in an even number, though — there are no cyclops spiders! Spider silk starts out in the silk glands as a watery gel of long protein chains, which is funnelled down a gradually tapering tube. The gel solidifies only when stretched, so rather than being squeezed out like toothpaste, it is pulled out by a motor-like valve in each spigot.
A battery of silk glands produces a wide array of fibres with different properties used for specific tasks — for instance, a dragline, snare, web support or egg case. These webs come in many different forms — from the much-admired orb webs of garden spiders and their relatives, to the much less welcome tangle webs of daddy-long-legs spiders.
Some types of webs are enduring structures — the often extensive funnel webs of large house spiders, for example, can last for years and accommodate a succession of different occupants. By contrast orb webs, produced by just four families of British spiders, are more fragile.
Wind and rain damage their structure, while the gluey coating on the spiral thread that ensnares flying insects is rendered ineffective by pollen and dust. As a result the webs are often rebuilt every night — an operation requiring the manufacture of some 20 metres of silk. Abandoning one web and building a new one every night would be pretty wasteful.
Instead, some orb-web-spinners recycle the amino acids that make up the silk proteins by ingesting the silk as they systematically dismantle their damaged webs. Other species simply discard the old silk but one American species uses it to wrap its egg sac. Silk is used to build webs and egg sacs, wrap up prey, help dispersal of young and as safety lines when escaping predators. Water spiders also use silk to hold an underwater air supply. Spiderlings disperse using silk.
They travel to a high point, raise their abdomens and let out one or more strands. On warm days with rising air currents, the spiderlings are lifted into the air and carried away. Spiders eat large numbers of insects.
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