Spiders
Monday, June 16th, 2008 by Decor Guru Subscribe To Our Feed
Many people are afraid of spiders. This fear is partly due to myths and to the notoriety of harmful species such as the brown recluse spider and the black widow spider. Several species of sac spiders are suspected of being responsible for most spider bites, especially ones occurring indoors. Sac spider venom is cytotoxic, causing tissues at the bite site to die. However, the vast majority of spiders are harmless to humans.
Spiders belong to the group of arthropods called Arachnids. There are more than 35,000 named species of spiders in the world with 3,000 of them making their home in North America. Spiders differ from insects in that spiders have 8 legs, not 6; they also have only 2 body regions (a cephalothorax and abdomen) instead of 3 (head, thorax, abdomen); and they lack wings and antennae, both of which insects possess. Finally, spiders possess unique organs beneath their abdomen called spinnerets. These 6 spinnerets allow the spider to produce silk throughout their entire life while only a few insects can produce silk and only during specific life stages.
Spiders do not attack in herds. Spiders do not lay in wait and attack people. Spiders do not lift the covers at night and crawl into bed to bite people as they are sleeping. Some spiders can jump but they are not intentionally jumping at humans to attack them. A spider generally bites a human because it was scared and bites to defend itself. Spiders generally prefer to live in undisturbed areas such as corners of the house or the eaves or in the garden where they can catch insects in peace.
Spiders lay eggs within a silken egg sac that is often ball-shaped and either hidden in a web, affixed to a surface, or carried by the female. Spiders may produce several egg sacs, each containing up to several hundred eggs. A spider grows by shedding its skin (molting), usually four to twelve times before maturity. In many species, the mature male often wanders about in search of a mate. Some species of spiders may live for years, but most spiders only survive for one season.
Spiders use a variety of tactics to capture prey. Some species are web builders that use webbing to ensnare their prey. Others are active hunters that actively search for their prey. Passive hunters are spiders that lay in wait for their prey rather than searching for it.
In contrast to viewing spiders as hazardous, they should be welcomed as heralds of environmental health. Spiders are top carnivores, so when spiders are thriving, it means that plants and animals lower on the food chain must also be doing well. Spiders are a sign that at least some portion of the ecosystem is operating properly.
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