Eight Legs to Hold You Trivia Quiz

Answer: Mites

Specifically, the mite that causes scabies is Sarcoptes scabiei. Other mites are responsible for a whole range of human skin irritations, including grain itch and grocer's itch. Demodex mites (which commonly are responsible for mange in dogs and other domestic pets) may be involved in the skin disease rosacea, and dust mites aggravate many forms of dermatitis (as well as producing a strong allergic reaction in many that can produce asthma and hay fever symptoms). Charming little (literally - many are microscopic) beasts, eh?

Answer: Harvestmen

Their legs have led many to call these arachnids daddy-long-legs (often appending spider to that name, but they are not in fact spiders, belonging to an entirely different order, Opiliones, rather than Araneae). That name can lead to further confusion as it is often also used for crane flies (insects in the family Tulipidae). Harvestmen can be distinguished from spiders in a number of ways, if you care to get that close.

The most obvious difference is in appearance - harvestmen have a very broad connection between the abdomen and the cephalothorax (a body structure formed by a fusing of the head and thorax) so that their entire body looks like a single oval. Harvestmen do not have silk glands, so do not build webs, and none of them are venomous, unlike most spiders.

Answer: Goliath birdeaters

A member of the tarantula family (which means they have hairy legs, among other things), the goliath birdeater (Theraphosa blondi) is one of the largest spiders, depending on whether you consider weight or leg span. It is listed as the second-largest in leg span, beaten out by the pinkfoot goliath (Theraphosa apophysis), but is considered the heaviest, with weights up to 150g. That's a bit over 5 oz, for those of you who are more familiar with that unit of measurement.

They are referred to as birdeaters because of a well-known engraving from the 18th century showing one eating a hummingbird.

Although they have (rarely) been observed to eat small birds in the wild, their diet consist mostly of earthworms and toads, with the occasional rodent, and even sometimes snakes.

Answer: Cross spiders

Two cross spiders, named Arabella and Anita, went up on a mission to Skylab 3, which started on 28 July 1973. The purpose was to conduct an experiment that had been suggested by a Massachusetts high school student named Judith Miles, to investigate whether spiders could weave webs in a low-gravity environment.

It took them a couple of days to adjust to the new circumstances, but after two days Arabella began spinning a web, with Anita creating one shortly afterwards. The webs were somewhat less symmetrical than would be typical of the web of an earthbound cross spider, with thinner filaments, but definitely viable webs.

They can be seen on display in the Smithsonian Museum. Sadly, both spiders died before the end of the mission.

Answer: Hooded tickspiders

The proper name for this order of arachnids is recinulae, but the members of the 60 or so species in it are usually called hooded tickspiders, despite the fact that they are neither ticks nor spiders. One of their most obvious common features is called a cucullus, which is a Latin word for a hood. Like a hood, it can be raised to cover the head, or lowered to a position in which it covers the mouth region.

The hood is used by females to carry fertilised eggs until they hatch. The larvae only have six legs; they undergo a series of molts on the way to adulthood, in the process of which they develop the full set of eight legs.

Answer: Funnel web spiders

There is no uniformly agreed-on deadliest spider, because experts disagree on whether it should be based on the toxicity of the venom, or the frequency of bites that lead to death. While the latter used to be used, the development of effective anti-venine for many of the most toxic spider bites means that there are fewer deaths, even though the bite is just as toxic. Also, species which are found in areas with significant human populations will bite more people than those in more isolated areas. Anyway, no matter how you define it, the Sydney funnel web (Atrax robustus), one of the natives which lend support to Australia's claim to have most of the deadliest creatures around, is right up there.

The female funnel web is one of the few spiders which actually attack aggressively, and doesn't just bite defensively.

Their fangs are strong enough to penetrate clothing, and even soft shoes.

Answer: Vinegaroons

Vinegaroons are also sometimes called whip scorpions because their body shape resembles that of a scorpion, but with a long whip-like tail. The name vinegaroon is based on the fact that, when attacked, they defend themselves by spraying a liquid that is a mixture of acetic acid and octanoic acid.

The chemical in vinegar that is responsible for its characteristic smell is acetic acid, so the nickname seems obvious. They only use six of their eight legs for walking - the other two are used rather like the antennae of insects, as sensory organs. Vinegaroons do not produce venom - they kill their prey (cockroaches being a favorite food) by using their strong jaws to crush it.

Answer: Scorpions

Scorpions have large appendages called pedipalps (somewhat reminiscent of lobster claws in appearance) which they use to grasp and immobilise their prey, and a segmented tail which they characteristically carry curved up over their backs. The venomous stinger is at the end of the tail.

Although a scorpion sting can be quite painful, they are not usually dangerous to humans (but young children, elderly persons and those susceptible to allergic reactions should probably seek medical attention as a precaution). Most scorpions are found in the tropics, but their range (often assisted by unintentional transport with cargo) has extended to cover almost everywhere except Antarctica.

The northernmost wild scorpion population can be found on the Isle of Sheppey in the United Kingdom, where five colonies have become firmly established since they were introduced in the 1860s. Surprisingly (or not), the tourist bureau doesn't feature them strongly in their information about things to see and do while visiting Sheppey.

Answer: Bagheera spiders

The genus Bagheera consists of four species, all of which are found in Central America. It is unclear why these jumping spiders take their name from the black panther of Rudyard Kipling's 'Jungle Book', since they are not black, but fairly brightly colored. Bagheera kiplingi is the most herbivorous spider yet discovered (not hard, since most of them are definitely predatory rather than herbivorous).

They live in a kind of tree (members of the Mimosaceae family) which has bulges on the tips of its leaf called Beltian bodies, which they eat (in competition with ants who also consider it a prime food source).

This forms at least 90% of their diet, supplemented by nectar from the flowers. When this food source is depleted, they have been known to eat ant larvae and even each other - but starvation, not a preference for this food, is clearly the motivation.

Answer: Ticks

Ticks are a vector of a number of diseases, including Lyme disease, Rocky Mountain spotted fever, and tularemia. This means that they can transmit the disease without themselves suffering from it. In most cases, they carry the pathogen and transmit it to mammals (and occasionally reptiles) when they feed - as they suck their host's blood, and inject saliva which contains the pathogen.

A few species of tick carry a neurotoxin in their saliva that can cause paralysis - if you live in a region where these ticks are found, it is necessary to take care of yourself and your pets, regularly inspecting to make sure that no ticks have been picked up after any excursion in an area of long grass or dense foliage.