In paleontology, a Lazarus taxon (plural "taxa") is a taxon that disappears from one or more periods of the fossil record, only to appear again later. The term refers to the Gospel of John, in which Jesus is claimed to have raised Lazarus from the dead. Lazarus taxa occur either because of (local) extinction, later resupplied, or as a sampling artifact. The fossil record is imperfect (only a very small fraction of organisms become fossilized) and contains gaps not necessarily caused by extinction, particularly when the number of individuals in a taxon becomes very low.