zoexylocarya), representing a genus previously known only from fossils 15 to 20 million years old, were recognized in 20, respectively. Nightcap Oak ( Eidothea hardeniana and E.Coelacanth ( Latimeria), a member of a subclass (Actinistia) thought to have gone extinct 65 million years ago live specimens found in 1938.Chacoan Peccary ( Catagonus wagneri), known to scientists only from fossils before its discovery in 1975.In this last case, the term Lazarus taxon applied in neontology.Īnimals that are Lazarus taxa are often cited by cryptozoologists as former cryptids. Other living fossils however are also Lazarus taxa if these have been missing from the fossil record for substantial periods of time, such as applies for Coelacanths.įinally, the term "Lazarus species" is applied to organisms that have been rediscovered as being still alive after having been widely considered extinct for years, without ever having appeared in the fossil record. Living fossils may occur regularly in the fossil record, such as the lampshell Lingula. For example, a trilobite that gets eroded out of its Cambrian-aged limestone matrix, and reworked into Miocene-aged siltstone.Ī living fossil is an extant taxon that appears to have changed so little compared to fossil remains, that it is considered identical.
Later such fossils turn out to be freed from the original seam and refossilized in a younger sediment. Related but distinctive conceptsĪn Elvis taxon is a look-alike that has supplanted an extinct taxon.Ī zombie taxon is a taxon that contains specimens that have been collected from strata younger than the extinction of the taxon. Therefore, reappearance of Lazarus taxa probably reflects the rebound after a period of extreme rarity during the aftermath of such extinctions. However, there appears to be no link with the abundance of fossiliferous sites and the proportion of Lazarus taxa, nor have missing taxa been found in potential refuges. The fossil record is inherently imperfect (only a very small fraction of organisms become fossilized, and an even smaller fraction discovered before destruction) and contains gaps not necessarily caused by extinction, particularly when the number of individuals in a taxon is very low.Īfter mass extinctions, such as the Permian–Triassic extinction event, the Lazarus effect occurred for many taxa. Lazarus taxa are observational artifacts that appear to occur either because of (local) extinction, later resupplied, or as a sampling artifact. The term refers to the account in the Gospel of John, in which Jesus raised Lazarus from the dead. In paleontology, a Lazarus taxon (plural taxa) is a taxon that disappears for one or more periods from the fossil record, only to appear again later.
The takahe is an example of a Lazarus taxon.
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