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People often plant flowers and vegetables in the soil. By doing so, they improve the beauty of their surroundings, which often results in commercial benefits. The nutrients found in the soil may be credited to inconspicuous creatures beneath the surface—worms. Many people are disgusted by these curious-looking animals; however, they have always been a source of fascination for me and are creatures I want to research. Worms are known to be great fish bait, which is one reason I was first drawn to these creatures. When I was 9 years old, my brother-in-law invited me to go fishing in Prospect Park. The park is located just across the street from where I live. I was baffled when I saw him crouch down and pick up some branches. I was told to rummage through some of the moist areas in order to locate worms for our bait. When I excavated the moist areas, I assumed that worms like to hide beneath the topsoil. It seemed to me that the worms were playing a game of hide-and-seek, and that they could somehow detect my movements. As we continued our search for worms, I discovered that in parts of Prospect Park we were unable to locate any worms, while in other areas they were abundant. As I reflected on this, I wondered what environmental factors might have contributed to the varying worm populations. Why did specific areas of Prospect Park have more worms than other areas? Was the temperature too cold in some areas, or too warm in others? Were there factors affecting the soil (pH level too high/low, insufficient food, etc.)? Were certain regions occupied by predators? These are the questions I set out to answer as I prepared for my field expeditions. |
 Some of the worms Linda collected in Prospect Park. During my background research, I discovered that there are three major groups of worms: roundworms, flatworms, and segmented worms (www.amnh.org). Earthworms, the worms I am interested in, are segmented worms and belong to the phylum Annelida. They are the most complex of all worms, with five hearts (which are used to circulate blood throughout the organism) and a body that may be divided into 100 or more segments (www.nysite.com). Earthworms also have a unique way of breathing; they perform respiration through their skin (www.irishearthworm.com). In the past, many people considered earthworms to be pests that invaded their gardens. However, these little organisms are now known as Mother Nature's little helpers and have a reputation as some of the best fertilizers. The leaf litter they digest leaves behind a rich fertilizer known as worm cast. Furthermore, as an earthworm burrows through the soil, it promotes the movement of air, water, and minerals, thus aiding in the breakdown of organic materials (www.irishearthworm.com). A recent study by the United States Department of Agriculture (Nancarrow and Taylor, 1998, p. 2) tested the effects that worms would have on poorly fertilized soil. In this experiment, the researchers set up two containers. The first container, the control group, contained dead worms and grass seeds. The second container, the experimental group, contained live worms and grass seeds. The results clearly demonstrated the positive effects that worms have on poorly fertilized soil. The grass plants in Container 2 (with live worms) grew four times faster than the seeds in Container 1 (with dead worms). |
        
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