tarantula

Originally the name 'tarantula' was given to a species of wolf spider in Italy which was blamed for venomous spider bites which locals tried to cure by performing a dance. In fact the spider bites were inflicted by a species of widow spider. But the widow spiders are small and look insignificant, whilst wolf spiders are bigger and hairy, so the wolf spider was blamed. To this day many people judge how venomous a spider is on its size, which is completely inaccurate. Wolf spiders are harmless. These days the name 'tarantula' is used to describe any spider of the Theraphosid family. This family has something like 800 known species in Africa, Mid and South America and Asia, with many more no doubt still undiscovered. The tarantulas (or Theraphosids) are the giants of the spider world, the biggest with leg-spans which could cover a dinner plate (a Goliath Birdeater with a 12-inch leg-span I think is the record). Though some tarantulas live in trees, most are ground-dwellers and the live in burrows. They line the entrances of their burrows with silk. Though tarantulas have no senses of hearing or smell and very poor vision, they have a very developed sense of touch. The hairs on their legs can detect the slightest air or ground vibration, and the lines of silk they lay down around their burrows are almost like extentions of their legs. Any small animal touching one of those threads will instantly alert the tarantula. Tarantulas feed on anything from crickets, locusts and cockroaches to rodents, small snakes and small lizards. Despite the fact they are often known as 'bird-eating spiders' in the US, it is probably very rare for a tarantula to eat a bird, though tree-climbing tarantulas can easily help themselves to a chick when a parent bird is away from its nest. With their basic webs they are thought to be the earliest form of spider, date back over 350 million years. When threatened or annoyed, tarantulas rear up on their back legs and bare their fangs. Some can even make a hissing/rustling noise by rubbing bristles on their jaws together. Tarantulas do not eat solid food. When a tarantula feeds, it injects a digestive fluid into its prey through its fangs. The prey is then gradually liquidised and absorbed into the mouth in a similar way to water being absorbed into a sponge. Tarantulas breathe through gill-like openings in the underside of their abdomens called 'book lungs'. When tarantulas mate, the male inserts sperm from his pedipalps ('feelers') into an opening under the female's body. Female tarantulas are larger and stronger than the more spindly-looking males, can live anything up to ten or twenty years, maybe longer depending on the species. Once the male has reached full size he can't hope to live eighteen months at the most. Despite the hooks on his front legs (for holding the female's fangs) he maybe be eaten after (or even before) mating. Tarantulas shed their skins, on average once a year. They can cast off a damaged limb but re-grow it gradually, the new limb becoming bigger every time their shed their skin. The tarantula skin is an exoskeleton, made of keratin (the same material human nails are made of). Despite the fear and horror they install in so many people (who've learnt most of what they know about tarantulas from the movies) tarantulas have venom which is unable to endanger human life. In fact, there is no record of anyone being killed by a tarantula bite. Some New World species have hairs on their abdomens which they can flick off with their back legs. These can cause an itching/burning sensation if they come into contact with human skin. But let's be honest, tarantulas are probably more afraid of us than we are of them, and they are a major controller of destructive pests like cockroaches and locusts. In fact tarantulas make excellent pets. They are more likely to run away rather than attack, unless they are cornered. Tarantulas are certainly not made of rubber, as some movies would have us believe. They are just as much flesh and blood as we are.