Welcome to the Octopodal world of Spiders

The Spider Menu
Introduction Spider Anatomy The Silken Web
Feeding Ecology Reproductive Ecology Spiders and Man
Ecological Considerations Tarantula Myths Spiders and Evolution
Caring for your Tarantula A House-spider Safari Classification
Fear of Spiders Bibliography and Reviews Links

Introduction

Welcome to the wonderful world of spiders. Spiders are truly amazing animals, you can find them anywhere, though they do not actually live in the open oceans or the air, however many species are happy to go flying if the weather is right. This new improved aspect of my website has been written as a result of your continued interest in spiders, I hope you will be able to find information here that will help you truly enjoy the beauty of your local spider fauna more easily.


Now Tell me. Do you hate spiders? Do you really hate spiders?
 
No of course you don't!!!! You love spiders!!!
 
 

You love them because you know they are an important part of the ecological balance of this world, without them our lives would be much less pleasant, and much more fly ridden. They are clever, useful, diverse, fascinating and often beautiful as well. There are aeronautic spiders, designer spiders, spiders that hunt with a bolas, others that throw a net over their prey. There are perfumer spiders that use false pheromones to attract moths , aquanaut spiders that dive beneath the water and engineer spiders what build underground tunnels with well fitted doors. There are solitary spiders and highly social spiders, there are spider thieves and scavengers and free running hunters, their are even spiders that specialise in hunting other spiders.

Like all arachnids spiders are recognised because they possess 8 legs, they also have their body is divided into only two parts a prosoma (a combination of head and thorax) sometimes called the cephalothorax and the opisthosoma sometimes called an abdomen. They can be distinguished from other Arachnids because the prosoma is only separated from the opisthosoma by a narrow waist, in other Arachnids the whole body appears to be much more of a single unit, or else it really is a single unit.

What's in a Name

The word 'Arachnida' comes from the Greek word, really a name, 'Arachne'. Arachne was the daughter of Idmon of Colophon in Lydia (ancient Greece), a dyer by trade. Here is one variation of the tale of how spiders came to have her name.
  Arachne herself was a weaver, the best in all the known world. However in a foolish moment she challenged Athene the daughter of Zeus and the Goddess of, among other things, weaving, to a weaving competition. Arachne wove such a perfect cloth that Athene knew she beaten. The result of this was that Athene became so enraged with jealousy that she tore Arachne's cloth to shreds. Arachne herself became extremely depressed after this and in the end she hung herself. Athene stirred to remorse at the knowledge of what her anger had wrought turned the rope Arachne had used to hang herself into a web and Arachne herself into a spider so that the beauty of her spinning should not be lost to the world ever again.

Some Spider Facts

All spiders produce silk, but only some construct webs to catch their food, the others use their webs to varying degrees for making their homes and to protect their eggs.


Nearly all spiders (the Uloboridae are the exception) possess poison glands but very few of them are dangerous to humans, of the 600+ species in Britain only 12 (at least one of these is a recent human assisted colonist) are strong enough to pierce the human skin, and apart from allergies, none are more dangerous than a common wasp.
 
The most dangerous spider in the world is difficult to detail because danger is not an easy thing to classify. The Brazilian Wandering Spider Phoneutria fera is currently believed to have the most potent Neurotoxin of any known spider, it also has very large venom glands meaning it can bite several times in succession delivering venom each time. Its venom is so powerful a mere 0.006 mg (0.00000012 oz) will kill a mouse. It is an aggressive spider and bites readily, fortunately there is an antidote for its bite now. However the largest number of serious bites may come from a different group of spiders, the genus Latrodectus contains both the Australian Redback Spider and the N. American Black Widow as well as a number of other dangerous species found around the world. The Sydney Funnel Web spider Atrax robustus is another species that is commonly reported as biting people with serious medical consequences.



 
There are more than 35 000 known species of spider in the world. However scientists believe there may be many more than this still waiting to be discovered.
 
Most spiders have 8 eyes (though some have 6,4,2 or 0), as well as 8 legs, (by the way if you count the claws as separate leg section {which you shouldn't really} then their legs have 8 parts as well [ coxa, trochanter, femur, patella, tibia, tarsus, metatarsus, claws)
 
No human being has ever been officially recorded as having died as the result of a 'tarantula' bite.


All spiders are carnivorous and feed only on liquids, i.e. their preys natural juices and the breakdown products of external digestion (meaning they spit, exude or inject digestive juices onto/into their prey and suck up the resulting soup). So why not invite some to your next social do??
 
The first spiders lived about 400 million years ago in the Devonian era, but they didn't become really successful until about 300 million years ago in the Carboniferous era.
 
The largest known spider in the world is Goliath bird-eating spider from South America (Surinam, Guyana and French Guinea). Its scientific name is Theraphosa leblondi and it can have a legspan of up to 28 cm (11 ins). It is an aggressive spider and though available in many pet shop should not be kept as a first spider pet. The largest specimen recorded was a male, though females are heavier they tend to have shorter legs.
 
The smallest known spider in the world also comes from South America, a fully adult male Patu digua from Columbia measures about 0.37 mm (0.015 in). The smallest known female spider is Anapistula caecula from the Ivory Coast in West Africa, it measures 0.46 mm (0.018ins). It is worth mentioning because males are usually smaller than females in most spider species, but the male of this species has not been found yet, thus it may be the smallest known species when it is finally known.
 
While males are often smaller than females, the genus Nephila takes this to extremes and the male may be as much as 1,000 times smaller than his mate, so small in fact that there is no chance she will confuse him with dinner, or see him as a competitor for food resources.
 
New species of spiders are being discovered all the time, and even in England where the natural fauna is better known than in any other country there is an average of 1 new species reported each year.
 
Only about half the worlds spiders spin webs to catch their prey, the rest are hunters either actively stalking their prey or lying in ambush somewhere.
 
Some spiders can live a long time without food or water, the record is held by specimen of Steatoda bipunctata which survived for 18 months without either food or water.
 
Spiders often seem to move quickly, and they can. Tests in England in the 1970s revealed that specimens of Tegenaria atrica could run at 1.9 km/h or 1.18 mph over short distances. While this may not seem fast if we consider it in light of the spiders small size (330 times its own length in 10 seconds) it is the equivalent of a 2 metre tall man running 2 km in the same time, which would give him a speed of 720 km/h (480 mph).
 
The web of an average European garden spider contains 20 -30 metres (65 -98 ft) of silk, yet it weighs less than 0.5 mg (0.00017 oz).
 
The largest individual webs in the world are spun spiders in the genus Nephila, these may be 2 metres (6 ft) in diametre and can catch small birds and bats.
 
The largest webs of all are built by communal spiders. Ixeuticus socialis in Australia builds webs that may be 1.2 metres wide and 3.7 metres long (12 ft by 4 ft) and is claimed by some authorities to build the largest nest. However G. F. Masterman, once the British Ambassador to Paraguay, described social spiders there building webs 9 metres (30 ft) long and 2.4 metres (8 ft) wide in his book Seven Eventful Years in Paraguay (1888).
 
There are at least 20 different species of social spiders, that is spiders who live together and share a web and the food caught in it. There are also about 20 species that show varying degrees of tolerance for each other and are thus primitively social.
 
Most spiders live for one, or two years at the most, but some spiders will live much longer. Amid the spiders commonly known as Tarantulas females live much longer than males, and some species such as The Mexican Red-kneed Tarantula have been recorded living for up to 25 years.

 

 

 

 

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