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Cockatiels
The cockatiel (; ''Nymphicus hollandicus''), also known as weiro (also spelt weero), or quarrion, is a medium-sized parrot that is a member of its own branch of the cockatoo family endemism in birds, endemic to Australia (continent), Australia. They are prized as household pets and companion parrots throughout the world and are relatively easy to breed. As a caged bird, cockatiels are second in popularity only to the budgerigar. The cockatiel is the only member of the genus ''Nymphicus''. It was previously unclear whether the cockatiel was a crested parakeet or small cockatoo; however, more recent molecular studies have assigned it to its own subfamily, ''Nymphicinae''. It is, therefore, now classified as the smallest of the Cacatuidae (cockatoo family). Cockatiels are native to Australia, favouring the Australian wetlands, scrublands, and bushlands. Taxonomy and etymology Originally described by Scottish writer and naturalist Robert Kerr (writer), Robert Kerr in 1793 as ''Psi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cacatuidae
A cockatoo is any of the 21 parrot species belonging to the family (biology), family Cacatuidae, the only family in the superfamily Cacatuoidea. Along with the Psittacoidea (true parrots) and the Strigopoidea (large New Zealand parrots), they make up the order (biology), order Psittaciformes. The family has a mainly Australasian distribution, ranging from the Philippines and the eastern Indonesian islands of Wallacea to New Guinea, the Solomon Islands and Australia. Cockatoos are recognisable by the prominent Crest (feathers), crests and curved beak, bills. Their plumage is generally less colourful than that of other parrots, being mainly white, grey or black and often with coloured features in the crest, cheeks or tail. On average they are larger than other parrots; however, the cockatiel, the smallest cockatoo species, is a small bird. The phylogenetic position of the cockatiel remains unresolved, other than that it is one of the earliest offshoots of the cockatoo lineage. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cockatoo
A cockatoo is any of the 21 parrot species belonging to the family Cacatuidae, the only family in the superfamily Cacatuoidea. Along with the Psittacoidea (true parrots) and the Strigopoidea (large New Zealand parrots), they make up the order Psittaciformes. The family has a mainly Australasian distribution, ranging from the Philippines and the eastern Indonesian islands of Wallacea to New Guinea, the Solomon Islands and Australia. Cockatoos are recognisable by the prominent crests and curved bills. Their plumage is generally less colourful than that of other parrots, being mainly white, grey or black and often with coloured features in the crest, cheeks or tail. On average they are larger than other parrots; however, the cockatiel, the smallest cockatoo species, is a small bird. The phylogenetic position of the cockatiel remains unresolved, other than that it is one of the earliest offshoots of the cockatoo lineage. The remaining species are in two main clades. The five ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Companion Parrot
A companion parrot is a parrot kept as a pet that interacts abundantly with its human counterpart. Generally, most species of parrot can make excellent companions, but must be carefully managed around other common pet species like dogs and cats as they might be hostile towards them. Species of parrots that are kept as companions include large parrots, such as amazons, greys, cockatoos, eclectus, hawk-headed parrots, and macaws; (Species include hybrids like the Catalina macaw) mid-sized birds, such as caiques, conures, quakers, ''Pionus'', ''Poicephalus'', rose-ringed parakeets, and rosellas; and many of the smaller types, including ''Brotogeris'', budgies, cockatiels, parakeets, lovebirds, parrotlets and lineolated parakeets. Some species of lories and lorikeets are kept as pets but are quite messy, and often more popular as aviary birds. Hanging parrots and fig parrots are normally kept as aviary birds and not as pets. Some species as pygmy parrots and kakapos, night par ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johann Georg Wagler
Johann Georg Wagler (28 March 1800 – 23 August 1832) was a German herpetologist and ornithologist. Wagler was assistant to Johann Baptist von Spix, and gave lectures in zoology at the Ludwig Maximilian University of Munich after it was moved to Munich. He worked on the extensive collections brought back from Brazil by Spix, and published partly together with him books on reptiles from Brazil. Wagler wrote ''Monographia Psittacorum'' (1832), which included the correct naming of the blue macaws. In 1832, Wagler died of an accidental self-inflicted gunshot wound while out collecting in München-Moosach. Life Johann Georg Wagler was a German naturalist and scientist in the 19th century, whose works primarily focused on herpetology and ornithology (Beolens, Watkins & Grayson, 2011). Johan Georg Wagler was born on the 28th of March 1800, in the city of Nuremberg, where the Chancellor of the City Court was Wagler's father (Wagler, 1884). After taking up gymnastics at Nuremberg, J ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ecological Niche
In ecology, a niche is the match of a species to a specific environmental condition. Three variants of ecological niche are described by It describes how an organism or population responds to the distribution of resources and competitors (for example, by growing when resources are abundant, and when predators, parasites and pathogens are scarce) and how it in turn alters those same factors (for example, limiting access to resources by other organisms, acting as a food source for predators and a consumer of prey). "The type and number of variables comprising the dimensions of an environmental niche vary from one species to another ndthe relative importance of particular environmental variables for a species may vary according to the geographic and biotic contexts". See also Chapter 2: Concepts of niches, pp. 7 ''ff'' A Grinnellian niche is determined by the habitat in which a species lives and its accompanying behavioral adaptations. An Eltonian niche emphasizes that a spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MtDNA
Mitochondrial DNA (mtDNA or mDNA) is the DNA located in mitochondria, cellular organelles within eukaryotic cells that convert chemical energy from food into a form that cells can use, such as adenosine triphosphate (ATP). Mitochondrial DNA is only a small portion of the DNA in a eukaryotic cell; most of the DNA can be found in the cell nucleus and, in plants and algae, also in plastids such as chloroplasts. Human mitochondrial DNA was the first significant part of the human genome to be sequenced. This sequencing revealed that the human mtDNA includes 16,569 base pairs and encodes 13 proteins. Since animal mtDNA evolves faster than nuclear genetic markers, it represents a mainstay of phylogenetics and evolutionary biology. It also permits an examination of the relatedness of populations, and so has become important in anthropology and biogeography. Origin Nuclear and mitochondrial DNA are thought to be of separate evolutionary origin, with the mtDNA being derived from t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RRNA
Ribosomal ribonucleic acid (rRNA) is a type of non-coding RNA which is the primary component of ribosomes, essential to all cells. rRNA is a ribozyme which carries out protein synthesis in ribosomes. Ribosomal RNA is transcribed from ribosomal DNA (rDNA) and then bound to ribosomal proteins to form small and large ribosome subunits. rRNA is the physical and mechanical factor of the ribosome that forces transfer RNA (tRNA) and messenger RNA (mRNA) to process and translate the latter into proteins. Ribosomal RNA is the predominant form of RNA found in most cells; it makes up about 80% of cellular RNA despite never being translated into proteins itself. Ribosomes are composed of approximately 60% rRNA and 40% ribosomal proteins by mass. Structure Although the primary structure of rRNA sequences can vary across organisms, base-pairing within these sequences commonly forms stem-loop configurations. The length and position of these rRNA stem-loops allow them to create three-di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DNA Sequence
DNA sequencing is the process of determining the nucleic acid sequence – the order of nucleotides in DNA. It includes any method or technology that is used to determine the order of the four bases: adenine, guanine, cytosine, and thymine. The advent of rapid DNA sequencing methods has greatly accelerated biological and medical research and discovery. Knowledge of DNA sequences has become indispensable for basic biological research, DNA Genographic Projects and in numerous applied fields such as medical diagnosis, biotechnology, forensic biology, virology and biological systematics. Comparing healthy and mutated DNA sequences can diagnose different diseases including various cancers, characterize antibody repertoire, and can be used to guide patient treatment. Having a quick way to sequence DNA allows for faster and more individualized medical care to be administered, and for more organisms to be identified and cataloged. The rapid speed of sequencing attained with modern D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calyptorhynchinae
Described by French naturalist Anselme Gaëtan Desmarest in 1826, the genus ''Calyptorhynchus'' has two species of cockatoos. They are all mostly black in colour, and the taxa may be differentiated partly by size and partly by small areas of red, grey, and yellow plumage, especially in the tail feathers. Studies based on the mitochondrial DNA 12S gene fragment suggested that other sexually dichromatic species, the gang-gang cockatoo and the cockatiel may be the closest living relatives of ''Calyptorhynchus''. However, subsequent studies, including more genes confirm the morphological taxonomy with the gang-gang cockatoo most closely related to the galah, within the white cockatoo group, and with the cockatiel as a third distinct subfamily of cockatoos. The Yellow-tailed black cockatoo, Baudin's black cockatoo and Carnaby's black cockatoo Carnaby's black cockatoo (''Zanda latirostris''), also known as the short-billed black cockatoo, is a large black cockatoo endemic to s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear DNA
Nuclear DNA (nDNA), or nuclear deoxyribonucleic acid, is the DNA contained within each cell nucleus of a eukaryotic organism. It encodes for the majority of the genome in eukaryotes, with mitochondrial DNA and plastid DNA coding for the rest. It adheres to Mendelian inheritance, with information coming from two parents, one male and one female—rather than matrilineally (through the mother) as in mitochondrial DNA. Structure Nuclear DNA is a nucleic acid, a polymeric biomolecule or biopolymer, found in the nucleus of eukaryotic cells. Its structure is a double helix, with two strands wound around each other, a structure first described by Francis Crick and James D. Watson (1953) using data collected by Rosalind Franklin. Each strand is a long polymer chain of repeating nucleotides. Each nucleotide is composed of a five-carbon sugar, a phosphate group, and an organic base. Nucleotides are distinguished by their bases: purines, large bases that include adenine and guanine; and pyr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intron
An intron is any nucleotide sequence within a gene that is not expressed or operative in the final RNA product. The word ''intron'' is derived from the term ''intragenic region'', i.e. a region inside a gene."The notion of the cistron .e., gene... must be replaced by that of a transcription unit containing regions which will be lost from the mature messenger – which I suggest we call introns (for intragenic regions) – alternating with regions which will be expressed – exons." (Gilbert 1978) The term ''intron'' refers to both the DNA sequence within a gene and the corresponding RNA sequence in RNA transcripts. The non-intron sequences that become joined by this RNA processing to form the mature RNA are called exons. Introns are found in the genes of most organisms and many viruses and they can be located in both protein-coding genes and genes that function as RNA (noncoding genes). There are four main types of introns: tRNA introns, group I introns, group II introns, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subfamily
In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end subfamily botanical names with "-oideae", and zoological names with "-inae". See also * International Code of Nomenclature for algae, fungi, and plants * International Code of Zoological Nomenclature * Rank (botany) * Rank (zoology) In biological classification, taxonomic rank is the relative level of a group of organisms (a taxon) in an ancestral or hereditary hierarchy. A common system consists of species, genus, family, order, class, phylum, kingdom, domain. While ... Sources {{biology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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