Caenorhabditis elegans (C. elegans)

Soil, decaying organic matter, and compost piles

Microbes, primarily bacteria such as E. coli in laboratory settings

Free-living soil nematode; hermaphroditic reproduction is common, and it follows a rapid life cycle from egg to adult in 3 days.

Non-parasitic and harmless to humans; extremely beneficial as a model organism in biological research and genetics.