Neoendemism is one of two sub-categories of endemism, the ecological state of a species being unique to a defined geographic location. Specifically, neoendemic species are those that have recently arisen, through divergence and reproductive isolation or through hybridization and polyploidy in plants. Paleoendemism, the other sub-category, refers to species that were formerly widespread but are now restricted to a smaller area.
"Darwin's finches", residents of the Galápagos Islands, have been used since the 19th century as an example of how the descendants of one ancestor can evolve through adaptive radiation into several species as they adapt to different conditions on various islands. Charles Darwin wrote:
...one might really fancy that from an original paucity of birds in this archipelago, one species had been taken and modified for different ends."[1][2]
The Galápagos archipelago is also the home of paleoendemic species.[3]
The Santa Cruz cypress (Hesperocyparis abramsiana; formerly classified as Cupressus abramsiana) has a geographic range limited to a small section in the Monterey Bay region of California where subsea canyon topography reliably produces summer fog, owing to cold water upwelling. The U.S. Fish and Wildlife Service listed the species as endangered in 1987, due to increasing threats from habitat loss and disruption of natural forest fire regimes.[4] In 2016, the conservation status of the Santa Cruz cypress was reduced to threatened. The cited reasoning was a decrease in threats against their habitat.[5] However, a lengthy section of the 2016 federal report titled "Genetic introgression" (also known as introgressive hybridization) explains how the integrity of this species is also threatened by nearby horticultural plantings of a sister species, Monterey cypress, whose historically native range is nearby: on the opposite side of Monterey Bay. Hybridization is known to occur between the two endemics — as well as with a widely planted sister species native to Arizona: Arizona cypress. The ease of hybridization of cypress species in the American southwest has fostered a parallel history of taxonomic disagreements of where genus and species distinctions should apply.[6] It thus provides a case study of neoendemism in conifers. As well, it illustrates an element of ongoing human impact — wind-dispersed pollen contamination from horticultural plantings — that cannot easily be corrected to meet conservation goals.
^Waller, Thomas. "The evolutionary and biogeographic origins of the endemic Pectinidae (Mollusca: Bivalvia) of the Galápagos Islands (abstract)". Journal of Paleontology. 81: 929–950. doi:10.1666/pleo05-145.1. S2CID 86121432.
^U.S. Fish and Wildlife Service. 1987. Endangered and threatened wildlife and plants; Determination of endangered status for Cupressus abramsiana (Santa Cruz cypress). Federal Register 52: 675-679. https://ecos.fws.gov/docs/federal_register/fr1017.pdf
^U.S. Fish and Wildlife Service. 2016. Endangered and Threatened Wildlife and Plants; Reclassifying Hesperocyparis abramsiana (=Cupressus abramsiana) as Threatened. Federal Register Vol. 81. No. 33. https://www.govinfo.gov/link/fr/81/8408?link-type=pdf
^Rehfeldt, Gerald E (1997). "Quantitative analyses of the genetic structure of closely related conifers with disparate distributions and demographics: the Cupressus arizonica (Cupressaceae) complex". American Journal of Botany. 84 (2): 190–200. doi:10.2307/2446080. JSTOR 2446080. PMID 21712198.
References
Darwin, Charles (1845), Journal of researches into the natural history and geology of the countries visited during the voyage of H.M.S. Beagle round the world, under the Command of Capt. Fitz Roy, R.N (2nd. ed.), London: John Murray
Darwin, Francis (1887), "Chapter 1, The Foundations of the 'Origin of Species'", in Darwin, Francis (ed.), The life and letters of Charles Darwin, including an autobiographical chapter, vol. 2, London: John Murray, p. 141, PMC2604052
January 31, 2023
neoendemism, categories, endemism, ecological, state, species, being, unique, defined, geographic, location, specifically, neoendemic, species, those, that, have, recently, arisen, through, divergence, reproductive, isolation, through, hybridization, polyploid. Neoendemism is one of two sub categories of endemism the ecological state of a species being unique to a defined geographic location Specifically neoendemic species are those that have recently arisen through divergence and reproductive isolation or through hybridization and polyploidy in plants Paleoendemism the other sub category refers to species that were formerly widespread but are now restricted to a smaller area Contents 1 Examples 2 See also 3 Notes 4 ReferencesExamples Edit Four of the 14 finch species found on the Galapagos Archipelago Darwin s finches residents of the Galapagos Islands have been used since the 19th century as an example of how the descendants of one ancestor can evolve through adaptive radiation into several species as they adapt to different conditions on various islands Charles Darwin wrote one might really fancy that from an original paucity of birds in this archipelago one species had been taken and modified for different ends 1 2 The Galapagos archipelago is also the home of paleoendemic species 3 The Santa Cruz cypress Hesperocyparis abramsiana formerly classified as Cupressus abramsiana has a geographic range limited to a small section in the Monterey Bay region of California where subsea canyon topography reliably produces summer fog owing to cold water upwelling The U S Fish and Wildlife Service listed the species as endangered in 1987 due to increasing threats from habitat loss and disruption of natural forest fire regimes 4 In 2016 the conservation status of the Santa Cruz cypress was reduced to threatened The cited reasoning was a decrease in threats against their habitat 5 However a lengthy section of the 2016 federal report titled Genetic introgression also known as introgressive hybridization explains how the integrity of this species is also threatened by nearby horticultural plantings of a sister species Monterey cypress whose historically native range is nearby on the opposite side of Monterey Bay Hybridization is known to occur between the two endemics as well as with a widely planted sister species native to Arizona Arizona cypress The ease of hybridization of cypress species in the American southwest has fostered a parallel history of taxonomic disagreements of where genus and species distinctions should apply 6 It thus provides a case study of neoendemism in conifers As well it illustrates an element of ongoing human impact wind dispersed pollen contamination from horticultural plantings that cannot easily be corrected to meet conservation goals See also EditSpeciationNotes Edit Darwin 1845 pp 379 380 Darwin 1887 Waller Thomas The evolutionary and biogeographic origins of the endemic Pectinidae Mollusca Bivalvia of the Galapagos Islands abstract Journal of Paleontology 81 929 950 doi 10 1666 pleo05 145 1 S2CID 86121432 U S Fish and Wildlife Service 1987 Endangered and threatened wildlife and plants Determination of endangered status for Cupressus abramsiana Santa Cruz cypress Federal Register 52 675 679 https ecos fws gov docs federal register fr1017 pdf U S Fish and Wildlife Service 2016 Endangered and Threatened Wildlife and Plants Reclassifying Hesperocyparis abramsiana Cupressus abramsiana as Threatened Federal Register Vol 81 No 33 https www govinfo gov link fr 81 8408 link type pdf Rehfeldt Gerald E 1997 Quantitative analyses of the genetic structure of closely related conifers with disparate distributions and demographics the Cupressus arizonica Cupressaceae complex American Journal of Botany 84 2 190 200 doi 10 2307 2446080 JSTOR 2446080 PMID 21712198 References EditDarwin Charles 1845 Journal of researches into the natural history and geology of the countries visited during the voyage of H M S Beagle round the world under the Command of Capt Fitz Roy R N 2nd ed London John Murray Darwin Francis 1887 Chapter 1 The Foundations of the Origin of Species in Darwin Francis ed The life and letters of Charles Darwin including an autobiographical chapter vol 2 London John Murray p 141 PMC 2604052 Retrieved from https en wikipedia org w index php title Neoendemism amp oldid 1135854003, wikipedia, wiki, book, books, library,
