The ascomycete fungus Neurospora crassa is important as a model system for the role filamentous fungi can play in biomass deconstruction, environmental nutrient cycling, and pathogenic interactions. During the early years of genetic inquiry it was used in pioneering investigations of the nature of the gene leading to the description of the one-gene, one-enzyme hypothesis in 1941. The genus name, meaning "nerve spore" in Greek, refers to the characteristic striations on the spores. The first published account of this fungus was from an infestation of French bakeries in 1843.
N. crassa is used as a model organism because it is easy to grow and has a haploid life cycle that makes genetic analysis simple since recessive traits will show up in the offspring. Analysis of genetic recombination is facilitated by the ordered arrangement of the products of meiosis in Neurospora ascospores. Its entire genome of seven chromosomes has been sequenced.