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Sibley–Monroe Checklist
The Sibley–Monroe checklist is a list of bird species based on a study conducted by Charles Sibley and Burt Monroe. It drew on extensive DNA–DNA hybridization studies to reassess the relationships between modern birds. It was considered a landmark in ornithology on its release. The Sibley–Monroe assignment of individual species to families, and of families to orders remains controversial. Critics maintain that while it marks a leap forward so far as the evidence from DNA–DNA hybridization goes, it pays insufficient attention to other forms of evidence, both molecular and on a larger scale. There is no true consensus, but the broad middle-ground position is that the Sibley–Monroe classification, overall, is "about 80% correct". Research and debate concerning bird classification continue. There are 9994 species on the checklist. See also * Sibley–Ahlquist taxonomy of birds The Sibley–Ahlquist taxonomy is a bird Taxonomy (biology), taxonomy proposed by Charles Sibley an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bird
Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a four-chambered heart, and a strong yet lightweight Bird skeleton, skeleton. Birds live worldwide and range in size from the bee hummingbird to the common ostrich. There are over 11,000 living species and they are split into 44 Order (biology), orders. More than half are passerine or "perching" birds. Birds have Bird wing, wings 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 Flightless bird, loss of flight in some birds, including ratites, penguins, and diverse endemism, endemic island species. The digestive and respiratory systems of birds are also uniquely a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charles Sibley
Charles Gald Sibley (August 7, 1917 – April 12, 1998) was an American ornithologist and molecular biologist. He had an immense influence on the scientific classification of birds, and the work that Sibley initiated has substantially altered our understanding of the evolutionary history of modern birds. Sibley's taxonomy has been a major influence on the sequences adopted by ornithological organizations, especially the American Ornithologists' Union. Life and work Educated in California (A.B. 1940; Ph.D. 1948 in Zoology, University of California, Berkeley. Minor fields: Paleontology, Botany), he did his first fieldwork in Mexico in 1939 and 1941, then in Solomon Islands, Bismarck Archipelago, New Guinea, and the Philippines during World War II while on leave from the U.S. Navy, in which he was Ensign to Lieutenant in the Communications and Medical Service Corps. He was based for much of the war at Emirau Island, in what is now New Ireland Province of Papua New Guinea. His first ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Burt Monroe
Burt Leavelle Monroe Jr. (25 August 1930 – 14 May 1994, in Louisville, Kentucky) was an American ornithologist, a professor at the University of Louisville, a member of the American Ornithologists' Union (AOU) beginning in 1953. Among his major contributions to avian taxonomy was the work with Charles Sibley resulting in the so-called Sibley-Monroe classification. Biography Monroe was born in Louisville to Ethelmae Tuell and Burt Leavelle Monroe Sr. (1901–1968). Like his father, he too took an interest in birds as well as a wider interest in natural history and published his first note on short-eared owls in 1945. He obtained a bachelor's degree in biology at the University of Louisville and then joined the US Navy from 1953 to 1959 rising to become a Lieutenant and working as a flight instructor at Pensacola. He then joined the Louisiana State University and worked on expeditions to collect birds in Honduras. This led also to his doctoral dissertation on the birds of Hondu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DNA–DNA Hybridization
In genomics, DNA–DNA hybridization is a molecular biology technique that measures the degree of genetic similarity between DNA sequences. It is used to determine the genetic distance between two organisms and has been used extensively in phylogeny and taxonomy. Method The DNA of one organism is labelled, then mixed with the unlabelled DNA to be compared against. The mixture is incubated to allow DNA strands to dissociate and then cooled to form renewed hybrid double-stranded DNA. Hybridized sequences with a high degree of similarity will bind more firmly, and require more energy to separate them. An example is they separate when heated at a higher temperature than dissimilar sequences, a process known as " DNA melting". To assess the melting profile of the hybridized DNA, the double-stranded DNA is bound to a column or filter and the mixture is heated in small steps. At each step, the column or filter is washed; then sequences that melt become single-stranded and wash off. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sibley–Ahlquist Taxonomy Of Birds
The Sibley–Ahlquist taxonomy is a bird Taxonomy (biology), taxonomy proposed by Charles Sibley and Jon E. Ahlquist. It is based on DNA–DNA hybridization studies conducted in the late 1970s and throughout the 1980s. DNA–DNA hybridization is among a class of comparative techniques in molecular biology that produce distance data (versus character data) and that can be analyzed to produce phylogenetic reconstructions only using phenetic tree-building algorithms. In DNA–DNA hybridization, the percent similarity of DNA between two species is estimated by the reduction in hydrogen bonding between nucleotides of imperfectly complemented heteroduplex DNA (i.e., double stranded DNAs that are experimentally produced from single strands of two different species), compared with perfectly matched homoduplex DNA (both strands of DNA from the same species). Characteristics The classification appears to be an early example of Cladistics#Cladistic classification, cladistic classification b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
