Basic Information
The spider is one of the largest class of eight legged arthropods known as arachnids, closely related to scorpions and several other related classes. Spiders are generally characterised by the possession of two body segments - the cephalothorax (head and torso) to which the legs are attached, and the abdomen. Spiders do not possess antennae but do have a set of chelicerae (semi-prehensile armlets attached to the mouth) and the capacity to spin silk from glands in the abdomen.
With one exception, spiders are generally obligate carnivores and serve their needs with a venomous "bite" delivered by the chelicerae. Spider venom will vary depending on species, but generally includes a neurotoxin to paralyze prey and frequently a package of lytic enzymes to pre-digest it. Depending on species, some spiders also use their silk, coated with adhesive, to form a web in which prey can become trapped, making it easier to catch and envenom. The silk can also be used to cocoon captured prey, storing it alive and helpless for later feeding. Non web spinning spiders may hunt by running and pouncing (some being capable of impressively athletic leaps), by ambush (possibly using a silk tripwire) or using a type of silk lasso. Whether they pre-digest as part of envenomation or not, sooner or later a spider will inject its prey with digestive enzymes and then ingest the liquefied product1 - spiders do not have jaws as such or consume solid food.
Whilst they are definitely predators, spiders are not top predators in any known ecosystem and so have a variety of further defences against predation. Some are poisonous as well as venomous, or resemble creatures that are, others camouflage themselves in their environment or build elaborate decoy spiders out of debris. Some, like the tarantula have the ability to discharge a cloud of irritating hairs at an attacker instead. Regardless, spiders are still predated in turn by a variety of species - including humans.
See Also
- Spider Silk
- Dungeon Forest - a favored habitat of spiders, especially the giant versions.
- Trapdoor Alligator - a fictional creature that attacks similarly to some spiders.
- Fiction/News: 2060 - Humvee-sized, bulletproof meat-eating spiders attack
- News: Gossamer Silk, From Spiders Spun
- News: Mammoth backyard spider devours bird
- News: Spider builds life-sized decoys
- Event/News: Spider-infested ship turned back from Guam landing
- Event/News: Giant spider attacks in India
Sources
Game and Story Use
- When designing spider venom, paralysis is the obvious form of damage, possibly leading to death through respiratory arrest in the case of an overdose. The pre-digestion bit is probably straight hitpoint damage - maybe with a corrosion type.
- Even those which can't paralyze a human may inflict extreme pain (much as some wasp venoms with the same purpose do).
- Giant spiders are an RPG staple, in real life spiders less than an inch across are quite capable of killing an adult human.
- That said, very few species of spider are capable of inflicting a significant bite on humans (generally because their venom dose is designed for much smaller prey of different species) and only one or two of those are actually aggressive (again, because aggression towards something thousands of times your size would normally border on suicide). Combining the size of the tarantula with the venom of the brown recluse and the aggression of the Brazilian wanderer would likely spawn an impressive man-killer.
- The decoy building talent could be useful for some fantastic intelligent spider - the ability to make constructs or fetches being an obvious derivative.
- Spider silk isn't farmed in real life, but a fantasy species might farm spiders like silk worms, using biothaumaturgy or selective breeding to improve their habits and perhaps feeding them large insect prey to get big cocoons.