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Cockatiels
The cockatiel (; ''Nymphicus hollandicus''), also known as the weero/weiro or quarrion, is a medium-sized parrot that is a member of its own branch of the cockatoo family endemic to Australia. They are prized as exotic household pets and companion parrots throughout the world and are relatively easy to breed compared to other parrots. 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 is 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 subfamily of the Cacatuidae (cockatoo family). Cockatiels are native to Australia, favouring the Australian wetlands, scrublands, and bushlands. There are many different mutations of this bird. Taxonomy and etymology Originally described by J. F. Gmelin in an edition of Systema natura ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Cockatoo
A cockatoo is any of the 21 species of parrots 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 their 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 medium-sized. The phylogenetic position of the cockatiel remains unresolved, except that it is one of the earliest offshoots of the cockatoo lineage. The remaining species are in two main clades. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
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 children and 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 Amazon parrot, amazons, Psittacus, greys, cockatoos, Eclectus parrot, eclectuses, Red-fan parrot, hawk-headed parrots, and macaws (including hybrids like the Catalina macaw); mid-sized birds, such as caiques, conures, monk parakeet, Quaker parrots, cockatiels, ''Pionus'', ''Poicephalus'', rose-ringed parakeets, and rosellas; and many of the smaller types, including Budgerigar, budgies, ''Brotogeris'', parakeets, lovebirds, parrotlets and Barred parakeet, 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 fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
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 28 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, Johann Georg W ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
MtDNA
Mitochondrial DNA (mtDNA and mDNA) is the DNA located in the mitochondria organelles in a eukaryotic cell that converts chemical energy from food into adenosine triphosphate (ATP). Mitochondrial DNA is a small portion of the DNA contained in a eukaryotic cell; most of the DNA is in the cell nucleus, and, in plants and algae, the DNA also is found in plastids, such as chloroplasts. Mitochondrial DNA is responsible for coding of 13 essential subunits of the complex oxidative phosphorylation (OXPHOS) system which has a role in cellular energy conversion. Human mitochondrial DNA was the first significant part of the human genome to be sequenced. This sequencing revealed that human mtDNA has 16,569 base pairs and encodes 13 proteins. As in other vertebrates, the human mitochondrial genetic code differs slightly from nuclear DNA. Since animal mtDNA evolves faster than nuclear genetic markers, it represents a mainstay of phylogenetics and evolutionary biology. It also permits tra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
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 SSU rRNA, small and LSU rRNA, 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 Translation (biology), 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, though this ratio differs between Prokaryote, prokaryotes and Eukaryote, eukaryotes. Structure Although the primary structure of rRNA sequences can vary across organisms, Base pair, base-pairing within these sequ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
DNA Sequence
A nucleic acid sequence is a succession of bases within the nucleotides forming alleles within a DNA (using GACT) or RNA (GACU) molecule. This succession is denoted by a series of a set of five different letters that indicate the order of the nucleotides. By convention, sequences are usually presented from the 5' end to the 3' end. For DNA, with its double helix, there are two possible directions for the notated sequence; of these two, the sense strand is used. Because nucleic acids are normally linear (unbranched) polymers, specifying the sequence is equivalent to defining the covalent structure of the entire molecule. For this reason, the nucleic acid sequence is also termed the primary structure. The sequence represents genetic information. Biological deoxyribonucleic acid represents the information which directs the functions of an organism. Nucleic acids also have a secondary structure and tertiary structure. Primary structure is sometimes mistakenly referred to as "prim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
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 Zanda (bird), black c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
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 eukaryotes and many eukaryotic 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 I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
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 Resource (biology), 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 [and] the 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 ecology, behavioral adaptations. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
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 botanical subfamily names with "-oideae", and zoological subfamily names with "-inae". Detarioideae is an example of a botanical subfamily. Detarioideae is a subdivision of the family Fabaceae (legumes), containing 84 genera. Stevardiinae is an example of a zoological subfamily. Stevardiinae is a large subdivision of the family Characidae, a diverse clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ... of freshwater fish. See also * International Code of Nomenclature for algae, fungi, and plants * International Code of Zoological Nomenclature * Rank (botany) * Rank (zoolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
