A pioneer organism, also called a disaster taxon, is an organism that colonizes a previously empty area first, or one that repopulates vacant niches after a natural disaster, mass extinction or any other catastrophic event that wipes out most life of the prior biome.[1] A group of such organisms capable of continued procreation among themselves are a pioneer species.

Natural disaster

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After a natural disaster, common pioneer organisms include lichens and algae. Mosses usually follow lichens in colonization but cannot serve as pioneer organisms. These common pioneer organisms can have a preference in the temperatures they are in. Lichens are more inclined to be in regions with more rainfall, whereas algae and mosses have a preference of being in regions with more humidity.[2]

Pioneer organisms modify their environment and establish conditions that accommodate other organisms. In some circumstances, other organisms can be considered pioneer organisms. Birds are usually the first to inhabit newly-created islands, and seeds, such as the coconut, may also be the first arrivals on barren soil.

Extinction event

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Since the resolution of the fossil record is low, pioneer organisms are often identified as those that lived within hundreds, thousands, or a million years of the extinction event. For example, after the Permian–Triassic extinction event 252 million years ago, Lystrosaurus, a tusked therapsid, was considered a disaster taxon.[1]

See also

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References

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  1. ^ a b Sahney, S. & Benton, M.J. (2008). "Recovery from the most profound mass extinction of all time". Proceedings of the Royal Society B: Biological Sciences. 275 (1636): 759–65. doi:10.1098/rspb.2007.1370. PMC 2596898. PMID 18198148.
  2. ^ Jackson, Togwell (January 1971). "Study of the ecology of pioneer lichens, mosses, and algae on recent Hawaiian lava flows". Vol. 25.