Here's a very interesting article !.

The spider is used becuase there webs represent a crystal which is the basis for life.



Drug-test spiders weave their way home.
By Roger Highfield, Science Editor

A SPIDER'S skill at spinning its web is so obviously affected when it is under the influence of drugs that Nasa scientists believe the creature could help them to test the effects of chemicals.
Different drugs alter the architecture of the web spun by a house spider in various ways, according to research reported today in New Scientist.

Spiders on marijuana are too laid back to finish the job, while those dosed with the sedative chloral hydrate drop off before they can lay down more than a few silky filaments. On an "upper", such as the amphetamine benzedrine, the spider demonstrates great gusto but not much planning, leaving large holes in the structure. Caffeine jitters turn webs into a haphazard affair.

The deformity in the web is related to the toxicity and dose of the chemical. Using a computer program, a Nasa team at the Marshall Space Flight Centre in Alabama has analysed the alterations in the webs and thinks it will be possible to quantify these effects to measure toxicity.

The spider could then offer an eight-legged alternative to testing on mammals. The team has found that one of the most telling measures of toxicity is a decrease in the numbers of completed sides in the cells within a web. The greater the toxicity, the more sides that the spider fails to complete.