Nematode Habitat Use
Habitat use in roundworms must be divided into two classifications for free living nematodes and parasitic nematodes (Myers 2004). Generally, nematodes are found in almost all marine environments including seemingly uninhabitable habitats such as deep ocean trenches and hot springs (Poinar Jr. 3). Fresh water streams, lakes, ponds, and rivers also provide habitats where nematodes thrive in sediment and around plant roots. Finally, free living nematodes are present in large quantities in soil. Nematodes can even be found in ice. Basically, anywhere there is organic matter nematodes will be present and usually en masse.
While some feed on smaller organisms, free living roundworms feed largely on decaying organic matter and contribute to its breakdown in soil and marine sediment. Nematodes function in their habitat as decomposers and make nutrients and minerals available for the energy and nutritional needs of larger organisms (McSorley 2004). Thus, although they are not studied in as much depth as parasitic roundworms, they are still vital to understanding the basic workings of energy exchange and matter breakdown on earth.
Parasitic roundworms represent a smaller but much better known segment of the total number of nematode species. Their habitats are the tissues and digestive tracts of invertebrates, vertebrates and plants. Parasitic nematodes have been found in almost every documented species of animal, so they have a very wide range of habitats (Hodda 2004). Importantly, nematode habitats include human food sources, both animal and plant, as well as humans. As parasites, roundworms derive their nutrition from and are usually harmful to their hosts. Often they suck nutrients from the blood of their hosts and use this abundant source of nutrition to reproduce in large quantities.
Evolution & Phylogenetic Relationships
Features Shared by Nematodes with Related Groups