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60-503: Racosperma harpophyllum Acacia harpophylla , commonly known as brigalow , brigalow spearwood or orkor , is an endemic tree of Australia. The Aboriginal Australian group the Gamilaraay peoples know the tree as Barranbaa or Burrii . It is found in central and coastal Queensland to northern New South Wales . It can reach up to 25 m (82 ft) tall and forms extensive open-forest communities on clay soils. The tree

120-556: A cave environment limits an organism's ability to disperse, since caves are often not connected to each other. One hypothesis for how closely related troglobite species could become isolated from one another in different caves is that their common ancestor may have been less restricted to cave habitats. When climate conditions became unfavorable, the ancestral species was extirpated from the surface, but some populations survived in caves, and diverged into different species due to lack of gene flow between them. Isolated islands commonly develop

180-478: A euendemic the vicariance was geologic in nature, such as the movement of tectonic plates, but in a cryptoendemic the disjunct distribution was due to the extinction of the intervening populations. There is yet another possible situation that can cause a disjunct distribution, where a species is able to colonize new territories by crossing over areas of unsuitable habitat, such as plants colonizing an island – this situation they dismiss as extremely rare and do not devise

240-402: A holoendemic is a cosmopolitan species. Stenoendemics, also known as local endemics, have a reduced distribution and are synonymous with the word 'endemics' in the traditional sense, whereas euryendemics have a larger distribution -both these have distributions that are more or less continuous. A rhoendemic has a disjunct distribution . Where this disjunct distribution is caused by vicariance, in

300-422: A large estate. While studying at Angoulême , Bentham came across a copy of A. P. de Candolle 's Flore française , and became interested in the analytical tables for identifying plants. He immediately tested them on the first plant he saw. The result was successful and he applied it to every plant he came across. In London in 1823, he met English botanists. His uncle pushed him to study law at Lincoln's Inn . He

360-555: A length of up to 20 cm (7.9 in) and a width of 5 to 10 mm (0.2 to 0.4 in) with longitudinal nerves. The soft, dull, brown seeds within the pods are arranged longitudinally and have an oblong or broadly elliptic shape. They are flattened but thick with a length of 10 to 18 mm (0.4 to 0.7 in) and have a filiform funicle . Two species, brigalow ( A. harpophylla ) and gidgee ( A. cambagei ) form open woodlands on flat and gently undulating terrain on heavy and relatively fertile clay and clay-loam soils primarily in

420-437: A limited range. Paleoendemism is more or less synonymous with the concept of a ' relict species ': a population or taxon of organisms that were more widespread or more diverse in the past. A 'relictual population' is a population that currently occurs in a restricted area, but whose original range was far wider during a previous geologic epoch . Similarly, a 'relictual taxon' is a taxon (e.g. species or other lineage) that

480-554: A maximum height of approximately 12 m (39 ft), is somewhat smaller than brigalow, which can attain heights of 20 m (66 ft). In the north-western regions black gidgee ( A. argyrodendron ) replaces brigalow in many areas, while in Central-Western districts boree ( A. tephrina ) forms woodlands and shrublands, frequently on cracking clay soils and often in association with A. cambagei . Georgina gidgee ( A. georginae ) woodlands are found in more arid regions in

540-513: A much larger area, but died out in most of their range, are called paleoendemic , in contrast to neoendemic species, which are new species that have not dispersed beyond their range. The ginkgo tree, Ginkgo biloba , is one example of a paleoendemic species. In many cases biological factors, such as low rates of dispersal or returning to the spawning area ( philopatry ), can cause a particular group of organisms to have high speciation rates and thus many endemic species. For example, cichlids in

600-522: A name for. Traditionally, none of Myers and de Grave's categories would be considered endemics except stenoendemics. Some environments are particularly conducive to the development of endemic species, either because they allow the persistence of relict taxa that were extirpated elsewhere, or because they provide mechanisms for isolation and opportunities to fill new niches. Serpentine soils act as ' edaphic islands' of low fertility and these soils lead to high rates of endemism. These soils are found in

660-465: A number of endemics. Many species and other higher taxonomic groups exist in very small terrestrial or aquatic islands, which restrict their distribution. The Devil's Hole pupfish, Cyprinodon diabolis , has its whole native population restricted to a spring that is 20 x 3 meters, in Nevada 's Mojave Desert . This 'aquatic island' is connected to an underground basin; however, the population present in

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720-449: A number of other Acacia species also form structurally similar communities. Brigalow occurs from coastal regions receiving in excess of 900 mm (35 in) rainfall per year through to the semiarid 500 mm (20 in) rainfall region although it is primarily a semiarid zone species. Gidgee ( A. cambagei ) replaces brigalow as rainfall drops in western regions and extends from 650 to 300 mm (26 to 12 in). Gidgee, with

780-417: A rare event under natural circumstances, since pasture is at best sparse in these communities, consisting of Chloris , Setaria (syn. Paspalidium ), Dicanthium , Sporobolus and Eragrostis species. Endemic (ecology) Endemism is an important concept in conservation biology for measuring biodiversity in a particular place and evaluating the risk of extinction for species. Endemism

840-545: A remarkable linguistic aptitude. By the age of seven, he could speak French, German and Russian, and he learned Swedish during a short residence in Sweden while still a child. The family made a long tour through France, staying two years at Montauban , where Bentham studied Hebrew and mathematics in the Protestant Theological School. They eventually settled near Montpellier where Sir Samuel bought

900-611: A scheme for the preparation of a series of Floras or descriptions in the English language of the indigenous plants of British colonies and possessions. Bentham began with the Flora Hongkongensis in 1861, which was the first comprehensive work on any part of the little-known flora of China and Hong Kong, including Hong Kong croton . This was followed by the Flora Australiensis , in seven volumes (1863–1878),

960-405: A species that is endemic is "precinctive", which applies to species (and other taxonomic levels) that are restricted to a defined geographical area. Other terms that sometimes are used interchangeably, but less often, include autochthonal, autochthonic, and indigenous; however, these terms do not reflect the status of a species that specifically belongs only to a determined place. The word endemic

1020-504: A very restrictive range, due to the unique environmental characteristics. The Kula Volcano , one of the fourteen volcanoes in Turkey , is home to 13 endemic species of plants. Endemics might more easily become endangered or extinct because they are already restricted in distribution. This puts endemic plants and animals at greater risk than widespread species during the rapid climate change of this century. Some scientists claim that

1080-625: A wide variety of evolutionary histories, so researchers often use more specialized terms that categorize endemic species based upon how they came to be endemic to an area. Different categorizations of endemism also capture the uniqueness and irreplaceability of biodiversity hotspots differently and impact how those hotspots are defined, affecting how resources for conservation are allocated. The first subcategories were first introduced by Claude P. E. Favager and Juliette Contandriopoulis in 1961: schizoendemics, apoendemics and patroendemics. Using this work, Ledyard Stebbins and Jack Major then introduced

1140-437: A wider distributed taxon that has become reproductively isolated without becoming (potentially) genetically isolated – a schizoendemic has the same chromosome count as the parent taxon it evolved from. An apoendemic is a polyploid of the parent taxon (or taxa in the case of allopolyploids ), whereas a patroendemic has a lower, diploid chromosome count than the related, more widely distributed polyploid taxon. Mikio Ono coined

1200-457: Is also of interest in evolutionary biology , because it provides clues about how changes in the environment cause species to undergo range shifts (potentially expanding their range into a larger area, or becoming extirpated from an area they once lived), go extinct, or diversify into more species. The extreme opposite of an endemic species is one with a cosmopolitan distribution , having a global or widespread range. A rare alternative term for

1260-564: Is best known for his taxonomic classification of plants in collaboration with Joseph Dalton Hooker , his Genera Plantarum (1862–1883). He died in London in 1884. Bentham was born in Stoke, Plymouth , on 22 September 1800. His father, Sir Samuel Bentham , a naval architect , was the only brother of Jeremy Bentham to survive into adulthood. His mother, Mary Sophia Bentham , was a botanist and author. Bentham had no formal education but had

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1320-487: Is endemic to Earth. However, endemism is normally used only when a species has a relatively small or restricted range. This usage of "endemic" contrasts with "cosmopolitan." Endemics are not necessarily rare; some might be common where they occur. Likewise, not all rare species are endemics; some may have a large range but be rare throughout this range. The evolutionary history of a species can lead to endemism in multiple ways. Allopatric speciation , or geographic speciation,

1380-414: Is from Neo-Latin endēmicus , from Greek ἔνδημος, éndēmos , "native". Endēmos is formed of en meaning "in", and dēmos meaning "the people". The word entered the English language as a loan word from French endémique , and originally seems to have been used in the sense of diseases that occur at a constant amount in a country, as opposed to epidemic diseases, which are exploding in cases. The word

1440-434: Is only possible where 1.) the taxonomy of the species in question is not in dispute; 2.) the species distribution is accurately known; and 3.) the species have relatively small distributional ranges. In a 2000 article, Myers et al . used the standard of having more than 0.5% of the world's plant species being endemic to the region to designate 25 geographical areas of the world as biodiversity hotspots . In response to

1500-456: Is root-suckering and has hard, furrowed and almost black coloured bark. The glabrous or hairy branchlets are angular at extremities. Like most species of Acacia it has phyllodes rather than true leaves. The coriaceous , sericeous and evergreen phyllodes have a falcate shape with a length of 10 to 20 cm (3.9 to 7.9 in) and a width of 7 to 20 mm (0.3 to 0.8 in). They have many closely parallel nerves with three to seven of

1560-618: Is the sole surviving representative of a formerly diverse group. The concept of phylogenetic endemism has also been used to measure the relative uniqueness of the species endemic to an area. In measurements that incorporate phylogenetic endemism, branches of the evolutionary tree are weighted by how narrowly they are distributed. This captures not only the total number of taxa endemic to the area (taxonomic endemism), but also how distant those species are from their living relatives. Schizoendemics, apoendemics and patroendemics can all be classified as types of neoendemics. Schizoendemics arise from

1620-718: Is when two populations of a species become geographically separated from each other and as a result develop into different species. In isolated areas where there is little possibility for organisms to disperse to new places, or to receive new gene flow from outside, the rate of endemism is particularly high. For example, many endemic species are found on remote islands , such as Hawaii , the Galápagos Islands and Socotra . Populations on an island are isolated, with little opportunity to interbreed with outside populations, which eventually causes reproductive isolation and separation into different species. Darwin's finches in

1680-692: The Linnean Society of London from 1861 to 1874. He was elected a Foreign Honorary Member of the American Academy of Arts and Sciences in 1866. He was appointed CMG (Companion of St Michael & St George) in 1878. His foreign awards included the Clarke Medal of the Royal Society of New South Wales in 1879. Bentham's first publication was his Catalogue des plantes indigènes des Pyrénées et du Bas Languedoc (Paris 1826),

1740-491: The Royal Botanic Gardens, Kew . At the same time, he contemplated the abandonment of botanical work. However, he yielded to the persuasion of Sir William Jackson Hooker , John Lindley and other scientific friends. In 1855 he took up his residence in London, and worked at Kew for five days a week, with a brief summer holiday, from this time onwards until the end of his life. In 1857, the government sanctioned

1800-455: The law of real property . But the most remarkable production of this period was the Outline of a New System of Logic: With a Critical Examination of Dr. Whately's Elements of Logic (1827). In this the principle of the quantification of the predicate was first explicitly stated. This Stanley Jevons declared to be undoubtedly the most fruitful discovery made in abstract logical science since

1860-481: The 200 to 250 mm (7.9 to 9.8 in) rainfall belt. In New South Wales it is found from around Roto in the south to around Hungerford in the west and Willow Tree in the east along the Great Dividing Range . In Queensland it is found as far north as Townsville . The species was first formally described by the botanist George Bentham in 1864 as part of the work Flora Australiensis . It

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1920-573: The 300-700mm annual rainfall region of Eastern Australia. These woodlands extend from a northern extreme of 20° S into northern New South Wales. Brigalow and gidgee occur as mixed communities in some regions and are commonly associated with several other woody species, including overstorey species such as Eucalyptus coolabah , E. cambageana , Casuarina cristata , and a range of understorey species. A. tephrina , A. georginae and A. argyrodendron also occupy similar habitats and have similar habits and growth forms, but are less widespread, while

1980-960: The Balkan Peninsula, Turkey, Alps, Cuba, New Caledonia, South Africa, Zimbabwe, the North American Appalachians, and scattered distribution in California, Oregon, and Washington and elsewhere. For example, Mayer and Soltis considered the widespread subspecies Streptanthus glandulosus subsp. glandulosus which grows on normal soils, to be a paleoendemic, whereas closely related endemic forms of S. glandulosus occurring on serpentine soil patches are neoendemics which recently evolved from subsp. glandulosus . Obligate cave-dwelling species, known as troglobites, are often endemic to small areas, even to single individual caves, because cave habitats are by nature restricted, isolated, and fragmented. A high level of adaptation to

2040-571: The East African Rift Lakes have diversified into many more endemic species than the other fish families in the same lakes, possibly due to such factors. Plants that become endemic on isolated islands are often those which have a high rate of dispersal and are able to reach such islands by being dispersed by birds. While birds are less likely to be endemic to a region based on their ability to disperse via flight, there are over 2,500 species which are considered endemic, meaning that

2100-756: The Galápagos archipelago are examples of species endemic to islands. Similarly, isolated mountainous regions like the Ethiopian Highlands , or large bodies of water far from other lakes, like Lake Baikal , can also have high rates of endemism. Endemism can also be created in areas which act as refuges for species during times of climate change like ice ages . These changes may have caused species to become repeatedly restricted to regions with unusually stable climate conditions, leading to high concentrations of endemic species in areas resistant to climate fluctuations. Endemic species that used to exist in

2160-546: The above, the World Wildlife Fund has split the world into a few hundred geographical ' ecoregions '. These have been designed to include as many species as possible that only occur in a single ecoregion, and these species are thus 'endemics' to these ecoregions. Since plenty of these ecoregions have a high prevalence of endemics existing within them, many National Parks have been formed around or within them to further promote conservation. The Caparaó National Park

2220-601: The botanical descriptions for The Botany of the Voyage of H.M.S. Sulphur . The editor, Richard Brinsley Hinds , had been surgeon on HMS Sulphur 1835-41 while she explored the Pacific coast of the Americas . In 1854 he found the maintenance of a herbarium and library too expensive. He, therefore, offered them to the government on the understanding that they should form the foundation of such necessary aids to research in

2280-419: The butt, roots and living stems in response to fire damage. Both gidgee and blackwood, in contrast, have a limited capacity to resprout following fire damage. A notable exception to the fire tolerance of brigalow communities occurs in what are referred to as softwood scrubs, which are dense communities of brigalow and a range of particularly fire-sensitive species. Fire in any brigalow or gidgee woodland would be

2340-707: The concept by using WWF ecoregions and reptiles, finding that most reptile endemics occur in WWF ecoregions with high biodiversity. Other conservation efforts for endemics include keeping captive and semi-captive populations in zoological parks and botanical gardens. These methods are ex situ ("off-site") conservation methods. The use of such methods may not only offer refuge and protection for individuals of declining or vulnerable populations, but it may also allow biologists valuable opportunities to research them as well. George Bentham George Bentham CMG FRS FLS (22 September 1800 – 10 September 1884)

2400-583: The concept. In their view, everything is endemic, even cosmopolitan species are endemic to Earth, and earlier definitions restricting endemics to specific locations are wrong. Thus the subdivisions neoendemics and paleoendemics are without merit regarding the study of distributions, because these concepts consider that an endemic has a distribution limited to one place. Instead, they propose four different categories: holoendemics, euryendemics, stenoendemics and rhoendemics. In their scheme cryptoendemics and euendemics are further subdivisions of rhoendemics. In their view,

2460-518: The concepts of neoendemics and paleoendemics in 1965 to describe the endemics of California. Endemic taxa can also be classified into autochthonous, allochthonous, taxonomic relicts and biogeographic relicts. Paleoendemism refers to species that were formerly widespread but are now restricted to a smaller area. Neoendemism refers to species that have recently arisen, such as through divergence and reproductive isolation or through hybridization and polyploidy in plants, and have not dispersed beyond

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2520-609: The cool climates of mountain peaks are geographically isolated. For example, in the Alpes-Maritimes department of France, Saxifraga florulenta is an endemic plant that may have evolved in the Late Miocene and could have once been widespread across the Mediterranean Basin . Volcanoes also tend to harbor a number of endemic species. Plants on volcanoes tend to fill a specialized ecological niche , with

2580-590: The first flora of any large continental area that had ever been finished. His greatest work was the Genera Plantarum , begun in 1862, and concluded in 1883 in collaboration with Joseph Dalton Hooker . His most famous work, however, was the Handbook of the British flora , begun in 1853 and first published in 1858. This was used by students for over a century, running into many editions. After his death, it

2640-512: The nerves being more prominent than the others. When it blooms between July and October, it produces condensed inflorescences in groups of two to eight on racemes, usually appearing as axillary clusters. The spherical flower heads have a diameter of 5 to 8 mm (0.2 to 0.3 in) and contain 15 to 35 golden-coloured flowers. After flowering crustaceous and glabrous seed pods form that are subterete and straight to slightly curved. The pods are raised over and constricted between seeds and have

2700-481: The new line of thought was complete, and included a change from typology in taxonomy to an appreciation that "We cannot form an idea of a species from a single individual, nor of a genus from a single one of its species. We can no more set up a typical species than a typical individual." Bentham was awarded the Royal Medal of the Royal Society in 1859 and elected a Fellow in 1862. He served as president of

2760-677: The pool remains isolated. Other areas very similar to the Galapagos Islands of the Pacific Ocean exist and foster high rates of endemism. The Socotra Archipelago of Yemen, located in the Indian Ocean, has seen a new endemic species of parasitic leech, Myxobdella socotrensis, appear. This species is restricted to freshwater springs, where it may attach to and feed upon native crabs. Mountains can be seen as ' sky islands ': refugia of endemics because species that live in

2820-404: The presence of endemic species in an area is a good method to find geographical regions that can be considered priorities for conservation. Endemism can thus be studied as a proxy for measuring biodiversity of a region. The concept of finding endemic species that occur in the same region to designate 'endemism hotspots' was first proposed by Paul Müller in a 1973 book. According to him, this

2880-542: The result of a careful exploration of the Pyrenees in company with G. A. Walker Arnott (1799–1868), afterwards professor of botany in the University of Glasgow . In the catalogue Bentham adopted the principle from which he never deviated, of citing nothing at second-hand. This was followed by articles on various legal subjects: on codification , in which he disagreed with his uncle, on the laws affecting larceny and on

2940-484: The species is restricted to an area less than five million hectares (twelve million acres). Microorganisms were traditionally not believed to form endemics. The hypothesis 'everything is everywhere', first stated in Dutch by Lourens G.M. Baas Becking in 1934, describes the theory that the distribution of organisms smaller than 2 mm is cosmopolitan where habitats occur that support their growth. Endemism can reflect

3000-424: The term 'aneuendemics' in 1991 for species that have more or fewer chromosomes than their relatives due to aneuploidy . Pseudoendemics are taxa that have possibly recently evolved from a mutation. Holoendemics is a concept introduced by Richardson in 1978 to describe taxa that have remained endemic to a restricted distribution for a very long time. In a 2000 paper, Myers and de Grave further attempted to redefine

3060-572: The threatened nature of a geographic region. A similar pattern had been found regarding mammals, Lasioglossum bees, Plusiinae moths, and swallowtail butterflies in North America: these different groups of taxa did not correlate geographically with each other regarding endemism and species richness. Especially using mammals as flagship species proved to be a poor system of identifying and protecting areas of high invertebrate biodiversity. In response to this, other scientists again defended

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3120-489: The time of Aristotle . Before sixty copies had been sold the publisher became bankrupt and the stock went for wastepaper. The book passed into oblivion, and it was not until 1873 that Bentham's claims to priority were finally vindicated against those of Sir William Hamilton by Herbert Spencer . In 1836 he published his Labiatarum genera et species . In preparing this work he visited, between 1830 and 1834, every European herbarium, several more than once. The following winter

3180-712: Was called to the bar and in 1832 held his first and only legal brief . However, his interest in botany never flagged and he became secretary of the Horticultural Society of London from 1829 to 1840. In 1832, he inherited the property of his uncle, Jeremy Bentham . Having inherited his father's estate the previous year, he was now sufficiently well off to do whatever he wanted, which was botany , jurisprudence and logic . Bentham married Sarah Jones (1798–1881), daughter of Sir Harford Jones Brydges , on 11 April 1833; they did not have children. Bentham died at his London home on 10 September 1884, aged 83. He

3240-520: Was an English botanist , described by the weed botanist Duane Isely as "the premier systematic botanist of the nineteenth century". Born into a distinguished family, he initially studied law, but had a fascination with botany from an early age, which he soon pursued, becoming president of the Linnaean Society in 1861, and a fellow of the Royal Society in 1862. He was the author of a number of important botanical works, particularly flora. He

3300-518: Was first used in botany by Vaughan MacCaughey in Hawaii in 1917. A species is considered to be endemic to the area where it is found naturally, to the exclusion of other areas; presence in captivity or botanical gardens does not disqualify a species from being endemic. In theory, the term "endemic" could be applied on any scale; for example, the cougar is endemic to the Americas, and all known life

3360-566: Was formed in the Atlantic Forest , a biodiversity hotspot located in Brazil, in order to help protect valuable and vulnerable species. Other scientists have argued that endemism is not an appropriate measure of biodiversity, because the levels of threat or biodiversity are not actually correlated to areas of high endemism. When using bird species as an example, it was found that only 2.5% of biodiversity hotspots correlate with endemism and

3420-541: Was interred in Brompton Cemetery . Bentham's life spanned the Darwinian revolution, and his young colleague Joseph Dalton Hooker was Darwin 's closest friend and one of the first to accept Darwin's ideas. Until then, Bentham unquestioningly believed that species were fixed. In 1874 he wrote that "Fifteen years have sufficed to establish a theory of evolution by natural selection ". Bentham's conversion to

3480-729: Was passed in Vienna , where he produced his Commentationes de Leguminosarum generibus , published in the annals of the Vienna Museum. In 1842 he moved to Pontrilas in Herefordshire. His chief occupation for the next few years was his contributions to the Prodromus Systematis Naturalis Regni Vegetabilis , which was being carried on by his friend, A. P. de Candolle . In all these dealt with some 4,730 species. In 1844, he provided

3540-434: Was reclassified as Racosperma harpophyllum by Leslie Pedley and subsequently transferred back the genus Acacia in 2001. The type specimen was collected from around Rockhampton . The specific epithet is in reference to the falcate shape of the phyllodes on the tree. Species associated with these brigalow communities generally have a good capacity for re-sprouting following fire, and brigalow itself sprouts freely from

3600-469: Was used in biology in 1872 to mean a species restricted to a specific location by Charles Darwin . The less common term 'precinctive' has been used by some entomologists as the equivalent of 'endemic'. Precinctive was coined in 1900 by David Sharp when describing the Hawaiian insects, as he was uncomfortable with the fact that the word ' endemic ' is often associated with diseases. 'Precinctive'

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