Fascinating spiders

Spiders are not insects but arachnids, having not six but eight legs and neither antennae nor wings. "Just as well!" some of you will no doubt be saying for it has to be admitted that they are amongst the animals with the worst reputation. But in reality, the few things that we can hold against them are insufficient to justify the phobias they sometimes inspire in us. It is true that they are deadly and poisonous animals – for the insects and other small prey they eat. Severe incidents involving humans are very rare worldwide, and in French Guiana are extremely rare, if not virtually non-existent. The most peaceful of living organisms, trees, are in fact far more dangerous than these little creatures, wreaking far more damage when they fall. Should we not rather fear, and with good cause, the infinitely more dangerous phenomena we encounter on a daily basis and to which we are wholly indifferent? In fact, at the end of the day spiders are pretty useful. In certain places they occur in large numbers and consume large quantities of insects, thus playing a major role in regulating population numbers of undesirable pests and helping to curb their proliferation. Also, these little "creepy crawlies" are actually quite fascinating. To start with, all of them without exception have a spinneret which produces a form of silk that has mechanical properties (in terms of resistance and elasticity) which would make any self-respecting engineer green with envy. For instance, it has been calculated that an (enormous) cable of spider silk one centimetre in diameter (that is to say thinner than your little finger) would, were it to exist, be capable of stopping a Boeing 747 in mid-flight without snapping. This silk is produced in very fine strands and can be produced by the spider throughout its life, to stop it falling as it moves around, spin itself a shelter, make traps, truss up its prey, take part in breeding, and even travel through the air. Scientists are just beginning to pierce the secrets of this silk, and we are still far from being in a position where we could even dream of being able to synthetically produce this super material on an industrial scale. But spiders have more than one trick in their spinneret and have other secrets that we have yet to understand. For instance, the art of controlling yaw when dangling on a thread, so as not to spin round like a potholer on the end of his rope. Another cause for wonder is the ability spiders have to construct elaborate traps of varying dimensions depending upon the species, with the orbicular web being the peak of geometrical perfection. This sort of web is produced by garden or orbweaver spiders. It is the best known of all spiders’ webs but is no longer considered by scientists to be the most intricate. Nevertheless, its simple elegance and regularity are still a source of fascination due to the beauty of its structure and because of the countless questions it raises as to how the spider makes it. Right, that's enough chat, I hope I have at least partially convinced you, and that the following pictures will win you over wholly. PS: please promise that from now on you will not systematically accuse a spider of having bitten you in your sleep. Be honest, do you see a lot of them running around on your bed?

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