Habitat destruction is the number one threat to all insects, spiders, and their relatives. Pollution, pesticides, land development, logging, fires, cattle grazing, and violent storms are just some of the events that damage or destroy their habitats. Introduced, or exotic, plants and animals can also have devastating effects. They compete with native arthropods for food and space. Native arthropods are usually capable of dealing with organisms that they have evolved with over millions of years, but they are often defenseless against exotic predators and diseases.

Loss of habitat and competition with exotic species affect the availability of food, mates, and egg-laying and nesting sites. The reduction or loss of any one of these resources can make a species vulnerable to extinction (ehk-STINGK-shun). Extinct species have completely died out and will never again appear on Earth. Arthropods that are widely distributed or feed on a variety of plants or animals are less likely to become extinct, but those living in small fragile habitats with specialized feeding habits are more likely to become extinct when their habitats are disturbed or destroyed. The fossil record shows that extinction is a natural process. Yet today, the loss of thousands of species of plants and animals each year, mostly arthropods, is not the result of natural events but is a direct result of human activities.

Scientists, politicians, and concerned citizens around the world have joined together to establish laws that protect arthropods and their habitats. The United States Fish and Wildlife Service helps to protect species threatened with extinction. They list seventy-seven species of arthropods as Threatened or Endangered, including forty-four insects (mostly butterflies), twelve arachnids, and twenty-one crustaceans. Some countries set aside land as preserves specifically to protect arthropods and their habitats.

The World Conservation Union (IUCN) publishes a list of species threatened by extinction. It places species in the categories Extinct, Extinct in the Wild, Critically Endangered, Endangered, Vulnerable, Near Threatened, Data Deficient, or Least Concern. In 2003 the list included 1,252 species of insects, spiders, and other arthropods. The sad fact is that scientists will probably never know just how many arthropod species are threatened with extinction and need protection. For example, tropical rainforest and coral reef habitats are disappearing so quickly that scientists have little or no time to collect and study their arthropod species before they are lost forever. Humanity's health and well-being depend on preserving all life, not just species that are big, pretty, furry, or feathered. Maybe you can be one of the scientists of the future that helps to save an insect or spider from becoming extinct.



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