Nematodes are small multicellular organisms that have been used as biological models since the 1960s. For example, Caenorhabditis elegans is a free-living nematode worm, about 1mm in length, that lives in temperate soil environments. It is made up of about 1000 cells, and has a short life cycle of only two weeks. It was the first multicellular organism to have its whole genome sequenced. The book summarizes the importance of nematodes as model organisms in the fields of genetics, developme...

Nematodes are incontestably the most numerous and the most diverse metazoans in freshwater habitats, and these properties bestow exceptional significance to their role in the environment. An array of functional roles has been attributed to them: they are grazers on bacteria and primary producers, regulators of decomposition of plant material, predators, prey for other animals, and closely associated symbionts of bacteria and other organisms. Freshwater nematodes are central in the context ...