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Chatham Island Robin
The black robin or Chatham Island robin ( Moriori: ''karure'', mi, kakaruia; ''Petroica traversi'') is an endangered bird from the Chatham Islands off the east coast of New Zealand. It is closely related to the South Island robin (''P. australis''). It was first described by Walter Buller in 1872. The binomial commemorates the New Zealand botanist Henry H. Travers (1844–1928). Unlike its mainland counterparts, its flight capacity is somewhat reduced. Evolution in the absence of mammalian predators made it vulnerable to introduced species, such as cats and rats, and it became extinct on the main island of the Chatham group before 1871, being restricted to Little Mangere Island thereafter.Falla, R.A.,Sibson, R.B. and Turbott, E.G., illustrated by Elaine Power. (1979) The new guide to the birds of New Zealand and outlying islands. Collins, Auckland. Discovery and taxonomy The first mention of the black robin in science was at a presentation given by William Travers at the W ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Walter Buller
Sir Walter Lawry Buller (9 October 1838 – 19 July 1906) was a New Zealand lawyer and naturalist who was a dominant figure in New Zealand ornithology. His book, ''A History of the Birds of New Zealand'', first published in 1873, was published as an enlarged version in 1888 and became a New Zealand classic. Biography Buller was born at Newark, the Wesleyan mission at Pakanae in the Hokianga, the son of Rev. James Buller, a Cornish missionary who had helped convert the people of Tonga to Methodism. He was educated at Wesley College in Auckland. In 1854, he moved to Wellington with his parents, where he was befriended by the naturalist William John Swainson. In 1859 he was made Native Commissioner for the Southern Provinces. In 1871 he travelled to England and was called to the bar at the Inner Temple. Three years later he returned to Wellington and practised law. In 1862, he married Charlotte Mair at Whangārei. They were to have four children. Buller was the author of '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wētā
Wētā (also spelt weta) is the common name for a group of about 100 insect species in the families Anostostomatidae and Rhaphidophoridae endemic to New Zealand. They are giant flightless crickets, and some are among the heaviest insects in the world. Generally nocturnal, most small species are carnivores and scavengers while the larger species are herbivorous. Wētā are preyed on by introduced mammals, and some species are now critically endangered. Name Wētā is a loanword, from the Māori-language word ''wētā'', which refers to this whole group of large insects; some types of wētā have a specific Māori name. In New Zealand English, it is spelled either "weta" or "wētā", although the form with macrons is increasingly common in formal writing, as the Māori word ''weta'' (without macrons) instead means "filth or excrement". General characteristics Many wētā are large by insect standards and some species are among the largest and heaviest in the world. Their p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alleles
An allele (, ; ; modern formation from Greek ἄλλος ''állos'', "other") is a variation of the same sequence of nucleotides at the same place on a long DNA molecule, as described in leading textbooks on genetics and evolution. ::"The chromosomal or genomic location of a gene or any other genetic element is called a locus (plural: loci) and alternative DNA sequences at a locus are called alleles." The simplest alleles are single nucleotide polymorphisms (SNP). but they can also be insertions and deletions of up to several thousand base pairs. Popular definitions of 'allele' typically refer only to different alleles within genes. For example, the ABO blood grouping is controlled by the ABO gene, which has six common alleles (variants). In population genetics, nearly every living human's phenotype for the ABO gene is some combination of just these six alleles. Most alleles observed result in little or no change in the function of the gene product it codes for. However, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inbreeding
Inbreeding is the production of offspring from the mating or breeding of individuals or organisms that are closely related genetically. By analogy, the term is used in human reproduction, but more commonly refers to the genetic disorders and other consequences that may arise from expression of deleterious or recessive traits resulting from incestuous sexual relationships and consanguinity. Animals avoid incest only rarely. Inbreeding results in homozygosity, which can increase the chances of offspring being affected by recessive traits. In extreme cases, this usually leads to at least temporarily decreased biological fitness of a population (called inbreeding depression), which is its ability to survive and reproduce. An individual who inherits such deleterious traits is colloquially referred to as ''inbred''. The avoidance of expression of such deleterious recessive alleles caused by inbreeding, via inbreeding avoidance mechanisms, is the main selective reason for outcrossin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Population Bottleneck
A population bottleneck or genetic bottleneck is a sharp reduction in the size of a population due to environmental events such as famines, earthquakes, floods, fires, disease, and droughts; or human activities such as specicide, widespread violence or intentional culling, and human population planning. Such events can reduce the variation in the gene pool of a population; thereafter, a smaller population, with a smaller genetic diversity, remains to pass on genes to future generations of offspring through sexual reproduction. Genetic diversity remains lower, increasing only when gene flow from another population occurs or very slowly increasing with time as random mutations occur. This results in a reduction in the robustness of the population and in its ability to adapt to and survive natural selection, selecting environmental changes, such as Climate change (general concept), climate change or a shift in available resources. Alternatively, if survivors of the bottleneck are the i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene
In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a basic unit of heredity and the molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protein-coding genes and noncoding genes. During gene expression, the DNA is first copied into RNA. The RNA can be directly functional or be the intermediate template for a protein that performs a function. The transmission of genes to an organism's offspring is the basis of the inheritance of phenotypic traits. These genes make up different DNA sequences called genotypes. Genotypes along with environmental and developmental factors determine what the phenotypes will be. Most biological traits are under the influence of polygenes (many different genes) as well as gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maladaptive
In evolution, a maladaptation () is a trait that is (or has become) more harmful than helpful, in contrast with an adaptation, which is more helpful than harmful. All organisms, from bacteria to humans, display maladaptive and adaptive traits. In animals (including humans), adaptive behaviors contrast with maladaptive ones. Like adaptation, maladaptation may be viewed as occurring over geological time, or within the lifetime of one individual or a group. It can also signify an adaptation that, whilst reasonable at the time, has become less and less suitable and more of a problem or hindrance in its own right, as time goes on. This is because it is possible for an adaptation to be poorly selected or become more of a dysfunction than a positive adaptation, over time. Note that the concept of maladaptation, as initially discussed in a late 19th-century context, is based on a flawed view of evolutionary theory. It was believed that an inherent tendency for an organism's adaptations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petroica Traversi (AM LB2068) (cropped)
The black robin or Chatham Island robin (Moriori: ''karure'', mi, kakaruia; ''Petroica traversi'') is an endangered bird from the Chatham Islands off the east coast of New Zealand. It is closely related to the South Island robin (''P. australis''). It was first described by Walter Buller in 1872. The binomial commemorates the New Zealand botanist Henry H. Travers (1844–1928). Unlike its mainland counterparts, its flight capacity is somewhat reduced. Evolution in the absence of mammalian predators made it vulnerable to introduced species, such as cats and rats, and it became extinct on the main island of the Chatham group before 1871, being restricted to Little Mangere Island thereafter.Falla, R.A.,Sibson, R.B. and Turbott, E.G., illustrated by Elaine Power. (1979) The new guide to the birds of New Zealand and outlying islands. Collins, Auckland. Discovery and taxonomy The first mention of the black robin in science was at a presentation given by William Travers at the Welli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cross-fostering
Cross-fostering is a technique used in animal husbandry, animal science, genetic and nature versus nurture studies, and conservation, whereby offspring are removed from their biological parents at birth and raised by surrogates, typically of a different species, hence 'cross.' This can also occasionally occur in nature. Animal husbandry Cross-fostering young animals is usually done to equalize litter size. Individual animals born in large litters are faced with much more competition for resources, such as breast milk, food and space, than individuals born in smaller litters. Herd managers will typically move some individuals from a large litter to a smaller litter where they will be raised by a non-biological parent. This is typically done in pig farming because litters with up to 15 piglets are common. A sow with a large litter may have difficulty producing enough milk for all piglets, or the sow may not have enough functional teats to feed all piglets simultaneously. When this occ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tomtit
The tomtit (''Petroica macrocephala'') is a small passerine bird in the family Petroicidae The bird family Petroicidae includes 51 species in 19 genera. All are endemic to Australasia: New Guinea, Australia, New Zealand and numerous Pacific Islands as far east as Samoa. For want of an accurate common name, the family is often called th ..., the Australasian robins. It is endemic (ecology), endemic to the islands of New Zealand, ranging across the main islands as well as several of the New Zealand outlying islands, outlying islands. In Māori language, Māori, the North Island Tomtit is known as miromiro and the South Island Tomtit is known as ngirungiru. This bird has several other Māori language, Māori and English language, English names as well. There are several subspecies showing considerable variation in plumage and size. The species is not threatened and has adapted to the changes made to New Zealand's Biodiversity of New Zealand, biodiversity. Etymology The term ''to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clutch (eggs)
__NOTOC__ A clutch of eggs is the group of eggs produced by birds, amphibians, or reptiles, often at a single time, particularly those laid in a nest. In birds, destruction of a clutch by predators (or removal by humans, for example the California condor breeding program) results in ''double-clutching''. The technique is used to double the production of a species' eggs, in the California condor case, specifically to increase population size. The act of putting one's hand in a nest to remove eggs is known as "dipping the clutch". Size Clutch size differs greatly between species, sometimes even within the same genus. It may also differ within the same species due to many factors including habitat, health, nutrition, predation pressures, and time of year. Clutch size variation can also reflect variation in optimal reproduction effort. In birds, clutch size can vary within a species due to various features (age and health of laying female, ability of male to supply food, and abundan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mangere Island
Mangere Island (Moriori: ''Maung’ Rē'') is part of the Chatham Islands archipelago, located about east of New Zealand's South Island and has an area of . The island lies off the west coast of Pitt Island, south-east of the main settlement in the Chathams, Waitangi, on Chatham Island. Mangere and nearby Tapuaenuku ( Little Mangere) are the eroded remains of an ancient volcano of Pliocene age. Whakapa, the island's highest point, is above sea level. Forested until the 1890s, the island was largely cleared for sheep grazing. Rabbits and then cats were also introduced but later died out. Farmed until 1966, the island was then purchased by the New Zealand government and gazetted as a Nature Reserve.Mangere Island restoration (from the Department of Conservation website) The last sheep were removed i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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