Wednesday, November 20, 2019

Spider Essay Example | Topics and Well Written Essays - 1250 words

Spider - Essay Example To date, 40,000 species of spiders have been recorded. It has been said that there might be thousands more which have yet to be discovered. These types have been found in all parts of the world except for Antarctica. According to Carl Alexander, author of’ Spiders, volume 8 (1929)’, the kingdom of spiders is Animalia, the phylum is Arthropoda, the class is Arachnida, and the order is Araneae. (8) According to James H. Emerton, author of ‘The common spiders of United States (1961)’, the most interesting types are mouse spider and black widow spider. Mouse spider is discovered first in Australia, is not harmful to human, and its bite is dry. The black widow spider is found around the world, has a large body, and excretes poison secretion that is harmful to human nerve (25). The scientific name given to the black widow spider is ‘Latrodectus Hesperuses’. This spider is mostly found in the United States, mainly, North America. The spider got its na me from the fact that the female spiders usually eat the male spiders after mating. This characteristic of the female black widow spider makes a male spider to approach the female carefully and gradually. In order to mate, the male spider would vibrate the female spider’s web in a certain way so that the female recognizes it and allows it to mate with her. The male spiders are not as venomous as the females as their main purpose is to mate; hence, they spend their entire lifetime searching for mates and even stop feeding. The female black widow spider have been known to be quite venomous, however, it is not life threatening as it secretes only a small amount of poison when bites. The body structure of a female black widow spider and a male are very different. The females have a shiny black body which is relatively longer. Moreover, there is a red marking just below the abdomen. The females are poisonous than the males. The males, however, are almost half the size of females. They have longer and leaner legs and most of them have red and yellow marks at the back. Both males and females body is parted in two. Their jaws are strong which support poisonous fangs. They have a hard, long exoskeleton. According to Donald M. Tuttle and Edward W. Baker, authors of ‘Spider mites of the United States’, spiders have about six holes underneath their abdomen called eyes. The silk goes out from these holes to expose to the air, then, it converts to thread. Spider’s female form its web from an extremely thin elastic silky thread. They use the glands that are in the lower part of their abdomen to form the web (34). According to Maggie Daley, author of ‘Illinois insects and spiders’, spiders have eight legs, eight eyes, and they do not have wings or chewing organs. Moreover, their bodies consist of two parts, the chest and the external part. The chest part is consists of the head with the brain and eyes, the stomach, legs and the mouth. T he external part consists of lungs, heart, liver, reproductive organs and the glands that play important role in producing the silk. (14) The black widow spider is further categorized into three main types, the Northern Black widow Spider, the Western Black Widow Spider and the Southern black Widow Spider. The Northern black widow is mostly found in the north east parts of USA and south east Canada. The Western Black Widow is mainly found in the western parts of USA, Canada and some parts of Mexico. Furthermore, the

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