How many worm breeds are there?

Answer 1

There are at least 20,000 kinds of worms. They are found almost all over the world. Worms are universal in distribution, occurring in marine, freshwater, and terrestrial habitats. Some worms that live in the ground help to condition the soil (e.g., annelids, aschelminths). Many thrive as parasites of plants (e.g., aschelminths) and animals, including humans (e.g., platyhelminths, aschelminths). Several other worms may be free-living, or nonparasitic. There are worms that live in freshwater, seawater, and even on the seashore. Ecologically, worms form an important link in the food chains in virtually all the ecosystems of the world.

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