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Blue Pigeon
The blue pigeons are a genus, ''Alectroenas'', of birds in the dove and pigeon family Columbidae. They are native to islands in the western Indian Ocean. Taxonomy and evolution The genus ''Alectroenas'' was first described in 1840 by the English zoologist George Robert Gray with the Mauritius blue pigeon (''Alectroenas nitidissimus'') as the type species. The genus name combines the Ancient Greek ''alektruōn'', meaning "domestic cock", and ''oinas'', meaning "pigeon". The ''Alectroenas'' blue pigeons are closely interrelated and occur widely throughout islands in the western Indian Ocean. They are allopatric and can therefore be regarded as a superspecies. There are three extant species: the Madagascar blue pigeon, the Comoros blue pigeon, and the Seychelles blue pigeon. The three Mascarene islands were home to one species each, which are all extinct; the Mauritius blue pigeon, the Rodrigues blue pigeon, and the Réunion blue pigeon. The blue pigeons perhaps colonised the Mas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetics
Genetics is the study of genes, genetic variation, and heredity in organisms.Hartl D, Jones E (2005) It is an important branch in biology because heredity is vital to organisms' evolution. Gregor Mendel, a Moravian Augustinian friar working in the 19th century in Brno, was the first to study genetics scientifically. Mendel studied "trait inheritance", patterns in the way traits are handed down from parents to offspring over time. He observed that organisms (pea plants) inherit traits by way of discrete "units of inheritance". This term, still used today, is a somewhat ambiguous definition of what is referred to as a gene. Trait inheritance and molecular inheritance mechanisms of genes are still primary principles of genetics in the 21st century, but modern genetics has expanded to study the function and behavior of genes. Gene structure and function, variation, and distribution are studied within the context of the cell, the organism (e.g. dominance), and within the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tarsometatarsus
The tarsometatarsus is a bone that is only found in the lower leg of birds and some non-avian dinosaurs. It is formed from the fusion of several bones found in other types of animals, and homologous to the mammalian tarsus (ankle bones) and metatarsal bones (foot). Despite this, the tarsometatarsus of birds is often referred to as just the shank, tarsus or metatarsus. Tarsometatarsal fusion occurred in several ways and extents throughout bird evolution. Specifically, in Neornithes (modern birds), although the bones are joined along their entire length, the fusion is most thorough at the distal (metatarsal) end. In the Enantiornithes, a group of Mesozoic avialans, the fusion was complete at the proximal (tarsal) end, but the distal metatarsi were still partially distinct. While these fused bones are best known from birds and their relatives, avians are neither the only group nor the first to possess tarsometatarsi. In a remarkable case of parallel evolution, they were also pres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tibiotarsus
The tibiotarsus is the large bone between the femur and the tarsometatarsus in the leg of a bird. It is the fusion of the proximal part of the tarsus with the tibia. A similar structure also occurred in the Mesozoic Heterodontosauridae. These small ornithischian dinosaurs were unrelated to birds and the similarity of their foot bones is best explained by convergent evolution. See also *Bird anatomy References * Proctor, Nobel S. ''Manual of Ornithology: Avian Structure and Function''. Yale University Press Yale University Press is the university press of Yale University. It was founded in 1908 by George Parmly Day, and became an official department of Yale University in 1961, but it remains financially and operationally autonomous. , Yale Universi .... (1993) Bird anatomy {{ornithology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hackles
Hackles are the erectile plumage or hair in the neck area of some birds and mammals. In birds, the hackle is the group of feathers found along the back and side of the neck. The hackles of some types of chicken, particularly roosters, are long, fine, and often brightly coloured. These hackles may be used in fly fishing as lures. In mammals, the hackles are the hairs of the neck and back which become erect when the animal is fearful, as part of the fight-or-flight response, or to show dominance over subordinate animals. Raising the hackles causes the animal to appear larger, and acts as a visual warning to other animals. Raised hackles are used by grey wolves as a dominance behavior, by moose preparing to attack, and by cats and striped hyena which are fearful or threatened. The process by which the hair is raised is called piloerection. The contraction of the arrector pili muscle associated with each hair follicle The hair follicle is an organ found in mammalian skin. It r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ducula
''Ducula'' is a genus of the pigeon family Columbidae, collectively known as imperial pigeons. They are large to very large pigeons with a heavy build and medium to long tails. They are arboreal, feed mainly on fruit and are closely related to the other genus of fruit-eating doves, ''Ptilinopus''. Both genera display brightly coloured plumage, predominantly green, often with contrasting under-parts of purple, orange or red. Some ''Ducula'' have prominently swollen ceres. They have large gapes and swallow seeds whole, playing an important role in seed dispersal. Imperial pigeons are found in forests of southern Asia, New Guinea, northern Australia and the Pacific islands. Many species are nomadic, travelling long distances to exploit seasonal fruit sources. Some undertake migrations and all are strong fliers. Because of habitat loss and predation, species of ''Ducula'' are amongst the most threatened of avian species globally. Taxonomy The genus ''Ducula'' was introduced in 183 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gallicolumba
''Gallicolumba'' is a mid-sized genus of ground-dwelling doves (family Columbidae) which occur in rainforests on the Philippines. Local name 'punay' which is a general term for pigeons and doves. They are not closely related to the American ground doves ( genus ''Columbina'' and related genera). Rather, the present genus is closest to the thick-billed ground pigeon. This genus includes the bleeding-hearts known from the Philippines. Most are named for their vivid-red patch on the breast, which looks startlingly like a bleeding wound in some species and has reminded naturalists of a dagger stab. The diet of doves of this genus consists of fruits and seed. Systematics and extinctions ''Gallicolumba'' might be ranked as a (very small) subfamily, but the available data suggests that they are better considered part of a quite basal radiation of Columbidae which consists of many small and often bizarre lineages (e.g. '' Goura'' and '' Otidiphaps'' which are ecologically convergent to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extinction
Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point. Because a species' potential range may be very large, determining this moment is difficult, and is usually done retrospectively. This difficulty leads to phenomena such as Lazarus taxa, where a species presumed extinct abruptly "reappears" (typically in the fossil record) after a period of apparent absence. More than 99% of all species that ever lived on Earth, amounting to over five billion species, are estimated to have died out. It is estimated that there are currently around 8.7 million species of eukaryote globally, and possibly many times more if microorganisms, like bacteria, are included. Notable extinct animal species include non-avian dinosaurs, saber-toothed cats, dodos, m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oceania
Oceania (, , ) is a region, geographical region that includes Australasia, Melanesia, Micronesia, and Polynesia. Spanning the Eastern Hemisphere, Eastern and Western Hemisphere, Western hemispheres, Oceania is estimated to have a land area of and a population of around 44.5 million as of 2021. When compared with (and sometimes described as being one of) the continents, the region of Oceania is the smallest in land area and the list of continents and continental subregions by population, second least populated after Antarctica. Its major population centres are Sydney, Melbourne, Brisbane, Perth, Auckland, Adelaide, Honolulu, and Christchurch. Oceania has a diverse mix of economies from the developed country, highly developed and globally competitive market economy, financial markets of Australia, French Polynesia, Hawaii, Hawaii, New Caledonia, and New Zealand, which rank high in quality of life and Human Development Index, to the much least developed countries, less developed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Southeast Asia
Southeast Asia, also spelled South East Asia and South-East Asia, and also known as Southeastern Asia, South-eastern Asia or SEA, is the geographical United Nations geoscheme for Asia#South-eastern Asia, south-eastern region of Asia, consisting of the regions that are situated south of mainland China, east of the Indian subcontinent, and north-west of mainland Australia. Southeast Asia is bordered to the north by East Asia, to the west by South Asia and the Bay of Bengal, to the east by Oceania and the Pacific Ocean, and to the south by Australia (continent), Australia and the Indian Ocean. Apart from the British Indian Ocean Territory and two out of atolls of Maldives, 26 atolls of Maldives in South Asia, Maritime Southeast Asia is the only other subregion of Asia that lies partly within the Southern Hemisphere. Mainland Southeast Asia is completely in the Northern Hemisphere. East Timor and the southern portion of Indonesia are the only parts that are south of the Equator. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ptilinopus
The fruit doves, also known as fruit pigeons, are a genus (''Ptilinopus'') of birds in the pigeon and dove family (Columbidae). These colourful, frugivorous doves are found in forests and woodlands in Southeast Asia and Oceania. It is a large genus with over 50 species, some threatened or already extinct. Taxonomy The genus ''Ptilinopus'' was introduced in 1825 by the English naturalist William John Swainson with the rose-crowned fruit dove (''Ptilinopus regina'') as the type species. The genus name combines the Ancient Greek meaning "feather" with meaning "foot". The many species of this genus can be further grouped by geography and by certain shared characteristics. The fruit doves of the Sunda Islands and northern Australia, such as the pink-headed fruit dove and banded fruit dove, have comparatively longer tails than other species, and are notable for their solid colouration on the head, neck and breast, with a black band across the belly. Another grouping can be made of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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