Neoendemism

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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.

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Examples

Four of the 14 finch species found on the Galapagos Archipelago Darwin's finches.jpeg
Four of the 14 finch species found on the Galápagos Archipelago

"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.

See also

Notes

  1. Darwin 1845 , pp.  379–380
  2. Darwin 1887
  3. 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.
  4. 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
  5. 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
  6. 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.

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Cypress is a common name for various coniferous trees or shrubs of northern temperate regions that belong to the family Cupressaceae. The word cypress is derived from Old French cipres, which was imported from Latin cypressus, the latinisation of the Greek κυπάρισσος (kyparissos). Cypress trees are a large classification of conifers, encompassing the trees and shrubs from the cypress family (Cupressaceae) and many others with the word “cypress” in their common name. Many cypress trees have needle-like, evergreen foliage and acorn-like seed cones.

<i>Cupressus</i> Several genera of evergreen conifers

Cupressus is one of several genera of evergreen conifers within the family Cupressaceae that have the common name cypress; for the others, see cypress. It is considered a polyphyletic group. Based on genetic and morphological analysis, the genus Cupressus is found in the subfamily Cupressoideae. The common name "cypress" comes via the Old French cipres from the Latin cyparissus, which is the latinisation of the Greek κυπάρισσος (kypárissos).

<i>Cupressus macrocarpa</i> Species of conifer

Hesperocyparis macrocarpa is a coniferous tree. It is commonly known as the Monterey cypress and is one of several species of cypress trees endemic to California.

<span class="mw-page-title-main">Leyland cypress</span> Species of conifer

The Leyland cypress, Cupressus × leylandii, often referred to simply as leylandii, is a fast-growing coniferous evergreen tree much used in horticulture, primarily for hedges and screens. Even on sites of relatively poor culture, plants have been known to grow to heights of 15 metres (49 ft) in 16 years. Their rapid, thick growth means they are sometimes used to achieve privacy, but such use can result in disputes with neighbours whose own property becomes overshadowed. The tree is a hybrid of Monterey cypress and Nootka cypress. It is almost always sterile, and is propagated mainly by cuttings.

<i>Callitropsis nootkatensis</i> Species of conifer

Callitropsis nootkatensis, formerly known as Cupressus nootkatensis is a species of trees in the cypress family native to the coastal regions of northwestern North America. This species goes by many common names including: Nootka cypress, yellow cypress, Alaska cypress, Nootka cedar, yellow cedar, Alaska cedar, and Alaska yellow cedar. The specific epithet "nootkatensis" is derived from its discovery by Europeans on the lands of a First Nation of Canada, those lands of the Nuu-chah-nulth people of Vancouver Island, British Columbia, who were formerly referred to as the Nootka.

<i>Cupressus dupreziana</i> Species of conifer in the family Cupressaceae

Cupressus dupreziana, the Saharan cypress, or tarout, is a very rare coniferous tree native to the Tassili n'Ajjer mountains in the central Sahara desert, southeast Algeria, where it forms a unique population of trees hundreds of kilometres from any other trees. There are only 233 specimens of this endangered species, the largest about 22 m tall. The majority are estimated to be over 2000 years old, with very little regeneration due to the increasing desertification of the Sahara. Rainfall totals in the area are estimated to be about 30 mm annually. The largest one is named Tin-Balalan is believed to be the oldest tarout tree with a circumference of 12 meters or 36 feet.

<i>Cupressus arizonica</i> Species of conifer

Cupressus arizonica, the Arizona cypress, is a North American species of tree in the cypress family Cupressaceae, native to the southwestern United States and Mexico. Populations may be scattered rather than in large, dense stands.

<span class="mw-page-title-main">Arboretum at the University of California, Santa Cruz</span> Arboretum in Santa Cruz, California

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<span class="mw-page-title-main">Northern California coastal forests</span> Temperate coniferous forests ecoregion in northern California and southwestern Oregon

The Northern California coastal forests are a temperate coniferous forests ecoregion of coastal Northern California and southwestern Oregon.

<i>Cupressus goveniana</i> Species of conifer

Cupressus goveniana, now reclassified as Hesperocyparis goveniana, with the common names Californian cypress and Gowen cypress, is a species of cypress, that is endemic to California.

<i>Cupressus guadalupensis</i> Species of conifer

Cupressus guadalupensis, the Guadalupe cypress, is a species of cypress from Guadalupe Island in the Pacific Ocean off western North America.

<i>Cupressus abramsiana</i> Species of conifer

The Santa Cruz cypress is a species of North American tree within the Cypress family. The species is endemic to the Santa Cruz Mountains within the Santa Cruz and San Mateo counties of west-central California. The U.S. Fish and Wildlife Service listed the species on the Endangered Species Act in 1987 due to increasing threats from habitat loss and disruption of natural forest fire regimes. In 2016, the conservation status of the Santa Cruz cypress changed to Threatened. The cited reasoning was a decrease in threats against their habitat.

<i>Platanthera yadonii</i> Species of orchid

Platanthera yadonii, also known as Yadon's piperia or Yadon's rein orchid, is an endangered orchid endemic to a narrow range of coastal habitat in northern Monterey County, California. In 1998 this plant was designated as an endangered species by the United States government, the major threat to its survival being continuing land development from an expanding human population and associated habitat loss. One of the habitats of Yadon's piperia, the Del Monte Forest near Monterey, California, is the subject of a federal lawsuit, based upon endangerment of this organism along with several other endangered species.

<i>Cupressus forbesii</i> Species of conifer

Cupressus forbesii, now reclassified by some as Hesperocyparis forbesii, and with the common names Tecate cypress or Forbes' cypress, is a species of cypress native to southwestern North America.

<i>Lessingia germanorum</i> Species of flowering plant

Lessingia germanorum is a rare species of flowering plant in the family Asteraceae known by the common name San Francisco lessingia. It is endemic to California, where it is known from four populations in the Presidio of San Francisco and one occurrence on San Bruno Mountain south of San Francisco. It is a state and federally listed endangered species. The already rare plant is endangered by many processes, including invasive species, development, sand mining, off-road vehicles and bulldozers, habitat fragmentation, trampling, and pollution, as well as stochastic events.

The Bonny Doon Ecological Reserve is a nature preserve of 552 acres (2.23 km2) in the Santa Cruz Mountains of California, United States. The reserve protects several rare and endangered plant and animal species within an area known as the Santa Cruz Sandhills, an ancient seabed containing fossilized marine animals.

<i>Cupressus stephensonii</i> Species of conifer

Cupressus stephensonii is a species of conifer known as the Cuyamaca cypress, and is endemic to Southern California. It has been classified as Hesperocyparis stephensonii. It was previously listed as Cupressus arizonica subsp. stephensonii and Cupressus arizonica var. glabra.

<i>Cupressus nevadensis</i> Species of conifer

Cupressus nevadensis, now reclassified as Hesperocyparis nevadensis, with the common name Paiute cypress, is a species of cypress tree native to a small area in Sierra Nevada of California, in the western United States.

<span class="mw-page-title-main">Assisted migration</span> Intentional transport of species to a different habitat

According to A Dictionary of Ecology, assisted migration is "the intentional establishment of populations or meta-populations beyond the boundary of a species' historic range for the purpose of tracking suitable habitats through a period of changing climate...." It is therefore a nature conservation tactic by which plants or animals are intentionally moved to geographic locations better suited to their present or future habitat needs and climate tolerances — and to which they are unable to migrate or disperse on their own.

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