Lazarus taxon

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The takahe is an example of a Lazarus taxon.

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 term refers to the story in the Gospel of John, in which Jesus raised Lazarus from the dead.

Potential explanations[edit]

Lazarus taxa are observational artifacts that appear to occur either because of (local) extinction, later resupplied, or as a sampling artifact. 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.

After mass extinctions, such as the Permian–Triassic extinction event, the Lazarus effect occurred for many taxa. 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. Therefore, reappearance of Lazarus taxa probably reflects the rebound after a period of extreme rarity during the aftermath of such extinctions.[1]

Related but distinctive concepts[edit]

An Elvis taxon is a look-alike that has supplanted an extinct taxon.

A zombie taxon is a taxon that contains specimens that have been collected from strata younger than the extinction of the taxon. Later such fossils turn out to be freed from the original seam and refossilized in a younger sediment. For example, a trilobite that gets eroded out of its Cambrian-aged limestone matrix, and reworked into Miocene-aged siltstone.

A living fossil is an extant taxon that appears to have changed so little compared to fossil remains, that it is considered identical. Living fossils may occur regularly in the fossil record, such as the lampshell Lingula.

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.

Finally, 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. In this last case, the term Lazarus taxon applied in neontology.

Animals that are Lazarus taxa are often cited by cryptozoologists as former cryptids.[2][3]

Reappearing fossil taxa[edit]

Coelacanth Latimeria chalumnae
  • Chacoan Peccary (Catagonus wagneri), known to scientists only from fossils before its discovery in 1975.[4]
  • Coelacanth (Latimeria), a member of a subclass (Actinistia) thought to have gone extinct 66 million years ago; live specimens found in 1938.
  • Nightcap Oak (Eidothea hardeniana and E. zoexylocarya), representing a genus previously known only from fossils 15 to 20 million years old, were recognized in 2000 and 1995, respectively.
  • Gracilidris, a genus of dolichoderine ants thought to have gone extinct 15-20 million years ago was found in Paraguay, Brazil, and Argentina and described in 2006.
  • Laotian Rock Rat (Laonastes aenigmamus), a member of a family (Diatomyidae) thought to have gone extinct 11 million years ago; found in 1996.
  • Majorcan midwife toad (Alytes muletensis), described from fossil remains in 1977, living animals discovered in 1979.
  • Dawn Redwood (Metasequoia), a genus of conifer, was first described as a fossil from the Mesozoic Era by Shigeru Miki in 1941, but in 1943 a small stand was discovered in China in Modaoxi by Zhan Wang.
  • Monito del Monte (Dromiciops), a member of a clade (Microbiotheria) thought to have gone extinct 11 million years ago.
  • Monoplacophora, a class of molluscs believed to have gone extinct in the middle Devonian Period (c. 380 million years ago) until living members were discovered in deep water off Costa Rica in 1952.
  • Mountain Pygmy Possum (Burramys parvus), Australia's only truly hibernating marsupial, known originally from the fossil record and then discovered in 1966.
  • Wollemi Pine (Wollemia), a species previously known only from fossils from 2 to 90 million years old representing a new genus of Araucariaceae, was discovered in 1994.

Reappearing IUCN red list species[edit]

Plants[edit]

Café marron Ramosmania rodriguesii.

Cultivars[edit]

Protostomes[edit]

Fish[edit]

Amphibians[edit]

Mammals[edit]

Reptiles[edit]

Birds[edit]

See also[edit]

References[edit]

  1. ^ Wignall, P. B.; Benton, M. J. (1999). "Lazarus Taxa and Fossil Abundance at Times of Biotic Crisis". Journal of the Geological Society 156. 
  2. ^ Shuker, K.P.N. (2002). The New Zoo: New and Rediscovered Animals of the Twentieth Century. House of Stratus. 
  3. ^ *Heuvelmans, Bernard. On The Track Of Unknown Animals. (New York: Hill and Wang, 1959.
  4. ^ Naish, Darren (2008-11-24). "New, obscure, and nearly extinct rodents of South America, and... when fossils come alive". Tetrapod Zoology. Retrieved 2008-12-13. 
  5. ^ C.A. McGuinness (2004). Xylotoles costatus. 2006. IUCN Red List of Threatened Species. IUCN 2006. www.iucnredlist.org. Retrieved on 17 March 2007.
  6. ^ Miguel Carles-Tolrá, Pablo C. Rodríguez & Julio Verdú (2010). "Thyreophora cynophila (Panzer, 1794): collected in Spain 160 years after it was thought to be extinct (Diptera: Piophilidae: Thyreophorini)". Boletín de la Sociedad Entomológica Aragonesa (S.E.A.) 46: 1–7.
  7. ^ Gehrman, Rare Birds.
  8. ^ Extraordinary Tale of the Bermuda Petrel and the Man Who Brought It Back from Extinction" (Boston: Beacon Press, 2012).
  9. ^ Ghost Bird 2009.

External links[edit]