When one thinks of earthworms usually one thinks about slimy and nasty creatures that are only used for fishing. Wrong! If there were no worms on earth, farms and many plants could not be properly maintained. This paper will explain how important earthworms are to the earth and to our environment. In addition, this paper will cover the origin of an earthworm, the anatomy and other important characteristics.
The origin of earthworms were said to be on earth around 200 millions ago. Their ancestors were marine worms, existing before there was even soil on this planet and vegetation. These worms underwent a slow process of adapting themselves to a new environment. If worms were on earth, they would have been wiped out due to the ice age. The early European settlers brought them back to North America during the 17th and 18th centuries. Many famous scientists studied earthworms such as Aristotle and Charles Darwin. Aristotle called earthworms "bowels of the earth".
Many people do not know how earthworms get around without features that other animals have. For example, earthworms have no eyes to see where they are going underground. They use the lights and vibrations from the ground to direct them on where they are going. Their skin is very sensitive to touch and chemicals of any kind. In addition, worms have sense organs that work like their noses. They are located in the front of the worms head.
Earthworms obtain their food very differently and eat lots of nutrients. For example, they do not have any teeth so earthworms use their mouth muscles in order to obtain food. At night, the earthworms come to the surface to take fallen leaves and grass clippings into their burrow to eat. Most the time, night crawlers eat soil while traveling through it and gain all their nutrients. They also use soil to help digest their food. Some earthworms are able to eat their own weight each day. They also produce 60% percent of urine, which contains a high level of nitrogen. The exchange gases though their skin and eliminates cellular waste and excess water through excretory tubules called nephridia.
All earthworms get their air though their skin, because they do not have any lungs. They are just like humans absorbing oxygen and breathing carbon dioxide. When it rains many earthworms come to the surface, because water can block the air through the skin, which causes them to suffocate. This event is very dangerous during the day because earthworms can die when exposed to UV sunlight, be stepped on or even be eaten by a bird. They can get oxygen from little small portions of water. Worms should not be in direct sunlight. They are sensitive to light, that's why they spend their time underground. In very hot days, earthworms would leave their beds. Earthworms have an other name they go by. The name night crawlers got their name because people thought they come and walk around at night time. They are found only in rich and productive soils and that therefore it is the rich soil that aids earthworms.
Earthworms live in a tunnel called a burrow. There are two types of burrows: temporary and permanent. Temporary are burrows that earthworms move from one place to other looking for food. Permanent burrows are the actual homes to the earthworms. They are usually in a good environment and near a good food source. The permanent burrows are formed vertically. Permanent burrows have numerous branches and side tunnels. Earthworms live in these burrows for the rest of their life. Researches indicated that the night crawler is a slow builder of burrows, taking from four to six weeks to burrow only eight inches into the soil. Many burrows are destroyed by moles. The night crawler will begin repairs immediately and complete them in a matter of days or weeks. Up to two-thirds of the space in the ground is made up...