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Geospiza Fortis
The medium ground finch (''Geospiza fortis'') is a species of bird in the family Thraupidae. It is endemic to the Galapagos Islands. Its primary natural habitat is tropical shrubland. One of Darwin's finches, the species was the first which scientists have observed evolving in real-time. The population of medium ground finches has been experiencing inbreeding depression due to small population numbers. Inbreeding depression occurs when there is a decrease in fitness due to individuals mating with genetic relatives. Typically, this leads to a loss of genetic diversity and a reduction in heterozygosity. Description Like the other members of its genus, the medium ground finch is strongly sexually dimorphic; the female's plumage is brown and streaky, while male's is solid black, with white tips to the undertail coverts. The bird measures in length—which falls between the lengths of the small and large ground finches. The bill of this species is quite variable in size, though ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Gould
John Gould (; 14 September 1804 – 3 February 1881) was an English ornithologist. He published a number of monographs on birds, illustrated by plates produced by his wife, Elizabeth Gould, and several other artists, including Edward Lear, Henry Constantine Richter, Joseph Wolf and William Matthew Hart. He has been considered the father of bird study in Australia and the Gould League in Australia is named after him. His identification of the birds now nicknamed "Darwin's finches" played a role in the inception of Darwin's theory of evolution by natural selection. Gould's work is referenced in Charles Darwin's book, ''On the Origin of Species''. Early life Gould was born in Lyme Regis, the first son of a gardener. Both father and son probably had little education. After working on Dowager Lady Poulett's glass house, his father obtained a position on an estate near Guildford, Surrey, and then in 1818, Gould Snr became foreman in the Royal Gardens of Windsor. Gould then be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Birds Of The Western Palearctic
''The Birds of the Western Palearctic'' (full title ''Handbook of the Birds of Europe, the Middle East, and North Africa: The Birds of the Western Palearctic''; often referred to by the initials ''BWP'') is a nine-volume ornithological handbook covering the birds of the western portion of the Palearctic zoogeographical region. Antecedents Earlier books of comparable scope include: * Dresser's nine-volume '' A History of the Birds of Europe, Including all the Species Inhabiting the Western Palearctic Region'' (1871–1896) * Witherby et al.'s five-volume ''Handbook of British Birds'' (1938–1941) Book ''The Birds of the Western Palearctic'' is a comprehensive regional avifauna for the Western Palearctic. It consists of 9 volumes, the first published in 1977 and the ninth in 1994. The main editor for the first five volumes was Stanley Cramp. Cramp died in 1987 and the subsequent volumes were edited by Duncan Brooks and Christopher Perrins. ''BWPs format and breadth influen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Birds Described In 1837
Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweight skeleton. Birds live worldwide and range in size from the bee hummingbird to the ostrich. There are about ten thousand living species, more than half of which are passerine, or "perching" birds. Birds have whose development varies according to species; the only known groups without wings are the extinct moa and elephant birds. Wings, which are modified forelimbs, gave birds the ability to fly, although further evolution has led to the loss of flight in some birds, including ratites, penguins, and diverse endemic island species. The digestive and respiratory systems of birds are also uniquely adapted for flight. Some bird species of aquatic environments, particularly seabirds and some waterbirds, have further evolved for swimming. Birds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endemic Birds Of The Galápagos Islands
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, the Cape sugarbird is found exclusively in southwestern South Africa and is therefore said to be ''endemic'' to that particular part of the world. An endemic species can be also be referred to as an ''endemism'' or in scientific literature as an ''endemite''. For example '' Cytisus aeolicus'' is an endemite of the Italian flora. '' Adzharia renschi'' was once believed to be an endemite of the Caucasus, but it was later discovered to be a non-indigenous species from South America belonging to a different genus. The extreme opposite of an endemic species is one with a cosmopolitan distribution, having a global or widespread range. A rare alternative term for a species that is endemic is "precinctive", which applies to s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geospiza
''Geospiza'' is a genus of bird in the tanager family Thraupidae. All species in the genus are endemic to the Galápagos Islands. Together with related genera, they are collectively known as Darwin's finches. Although in the past, they were classified in the bunting and American sparrow family Emberizidae, more recent studies have shown they belong in the tanager family. Taxonomy and species list The genus ''Geospiza'' was introduced in 1837 by the English ornithologist John Gould with the large ground finch as the type species. The genus name derives from the two Ancient Greek words (), meaning "earth", and (), a catch-all term for ''finch''-like birds. The member of the genus form part of a group collectively known as Darwin's finches. Although traditionally placed with the buntings and New World sparrows in the family Emberizidae, molecular phylogenetic studies have shown that Darwin's finches are members of the subfamily Coerebinae within the tanager family Thraupidae. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Santa Cruz Island (Galápagos)
Santa Cruz Island () is one of the Galápagos Islands with an area of and a maximum altitude of . Situated in the center of the archipelago, Santa Cruz is the second largest island after Isabela. Its capital is Puerto Ayora, the most populated urban centre in the islands. On Santa Cruz, there are some small villages, whose inhabitants work in agriculture and cattle raising. The island is an oval-shaped, long and wide shield volcano. Its summit contains a shallow caldera that has been largely buried by youthful pit craters and cinder cones with well-preserved craters. The most recent eruptions may have occurred only a few thousand years ago with the effusion of sparsely vegetated lava flows from vents on the north flank and along the summit fissure. A gigantic lava tube measuring over long is a tourist attraction on the island. As a testimony to its volcanic history there are two big holes formed by the collapse of a magma chamber: Los Gemelos, or "The Twins". Named after t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Avipoxvirus
''Avipoxvirus'' (avian pox) is a genus of viruses within the family ''Poxviridae''. ''Poxviridae'' is the family of viruses which cause the afflicted organism to have poxes as a symptom. Poxviruses have generally large genomes, and other such examples include smallpox and monkeypox. Members of the genus ''Avipoxvirus'' infect specifically birds. Avipoxviruses are unable to complete their replication cycle in non-avian species. Although it is comparably slow-spreading, ''Avipoxvirus'' is known to cause symptoms like pustules full of pus lining the skin and diphtheria-like symptoms. These diphtheria-like symptoms might include diphtheric necrotic membranes lining the mouth and the upper respiratory tract. Like other avian viruses, it can be transmitted through vectors mechanically such as through mosquitoes. There is no evidence that this virus can infect humans. ''Avipoxvirus'' is a virus that is brick-shaped and is usually 200 nanometres in diameter. This is much larger tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Philornis Downsi
''Philornis downsi'', also known as the avian vampire fly, is a species of fly ( Diptera, Muscidae) that was first recorded in Trinidad and Brazil in the 1990s. It has been accidentally introduced to the Galapagos Islands (Ecuador). Adults of ''P. downsi'' feed on fruit. Eggs are laid in bird nests and hatch into parasitic larvae that reside in the nest material and emerge at night to feed both internally and externally on the blood and flesh of developing nestlings. The parasite causes significant mortality in Darwin's finch Darwin's finches (also known as the Galápagos finches) are a group of about 18 species of passerine birds. They are well known for their remarkable diversity in beak form and function. They are often classified as the subfamily Geospizinae or t ... nestlings and threatens the survival of some rarer species such as the mangrove finch (''Camarhynchus heliobates'') and the medium tree finch (''C. pauper''). To protect the threatened finch populations, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endemic
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, the Cape sugarbird is found exclusively in southwestern South Africa and is therefore said to be ''endemic'' to that particular part of the world. An endemic species can be also be referred to as an ''endemism'' or in scientific literature as an ''endemite''. For example '' Cytisus aeolicus'' is an endemite of the Italian flora. '' Adzharia renschi'' was once believed to be an endemite of the Caucasus, but it was later discovered to be a non-indigenous species from South America belonging to a different genus. The extreme opposite of an endemic species is one with a cosmopolitan distribution, having a global or widespread range. A rare alternative term for a species that is endemic is "precinctive", which applies to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Large Ground Finch
The large ground finch (''Geospiza magnirostris'') is a species of bird. One of Darwin's finches, it is now placed in the family Thraupidae and was formerly in the Emberizidae. It is endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ... to the Galapagos Islands, and is found in the arid zone of most of the archipelago, though it is absent from the southeastern islands ( Floreana, Española, San Cristóbal, and Santa Fé). It is the largest species of Darwin's finch both in total size and size of beak. It has a large, short beak for cracking nuts to get food. Gallery File:Large ground finch (4229044630).jpg, left, Large ground finch File:Geospiza magnirostris.jpg, left, One of Darwin's finches. Charles and Chatham Islands, Galapagos Archipelago. References Geospiza ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Daphne Major
Daphne Major is a volcanic island just north of Santa Cruz Island and just west of the Baltra Airport in the Archipelago of Colón, commonly known as the Galápagos Islands. It consists of a tuff crater, devoid of trees, whose rim rises above the sea. Though easily accessible to most visitors to the Galápagos, the national park service has highly restricted visits to this island, and it is primarily used for scientific research. An intensive study of Darwin's finches was conducted here by biologists Peter and Rosemary Grant over a period of 20 years. They examined the behaviour and life cycles of finches, demonstrating the role of natural selection in producing biological evolution. Their efforts were documented in the Pulitzer Prize–winning book ''The Beak of the Finch''. Daphne is home to a variety of other birds including Galápagos martins, blue-footed booby, Nazca booby, short-eared owls, red-billed tropicbirds and magnificent frigatebirds. References *B. Rosemary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Character Displacement
Character displacement is the phenomenon where differences among similar species whose distributions overlap geographically are accentuated in regions where the species co-occur, but are minimized or lost where the species' distributions do not overlap. This pattern results from evolutionary change driven by biological competition among species for a limited resource (e.g. food). The rationale for character displacement stems from the competitive exclusion principle, also called Gause's Law, which contends that to coexist in a stable environment two competing species must differ in their respective ecological niche; without differentiation, one species will eliminate or exclude the other through competition. Character displacement was first explicitly explained by William L. Brown Jr. and E. O. Wilson in 1956: "Two closely related species have overlapping ranges. In the parts of the ranges where one species occurs alone, the populations of that species are similar to the other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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