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Southern Pied Babbler
The southern pied babbler (''Turdoides bicolor'') is a species of bird in the family Leiothrichidae, found in dry savannah of Botswana, Namibia, South Africa, and Zimbabwe. Description The southern pied babbler is a medium-sized cooperatively breeding passerine bird. Groups range in size from 2-16 adults, but pairs are rare. The species is sexually monomorphic, with males and females indistinguishable from physical characteristics. Each group comprises a dominant breeding pair that monopolise access to breeding opportunities. Recent genetic research has confirmed that these dominant pairs are responsible for more than 95% of young hatched. Occasional mixed parentage has been observed, but is predictable in most cases: subordinates primarily gain parentage when a new (unrelated) immigrant disperses into the group, or a new group is founded. All group members cooperate to help raise the young hatched from a single clutch. Clutch size varies between two and five, with a modal clutch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marakele National Park
Marakele National Park is a National Park, part of the Waterberg Biosphere in Limpopo Province, South Africa. Flora and fauna The park is accessible to all passenger vehicles, with the camp and tent sites on good roads. Also, approximately 80 km of roads within the park are accessible to all vehicles, the balance requiring a four-wheel drive vehicle. Marakele is home to the big five (buffalo did not exist in the park, but 20 disease-free buffalo (nine cows and eleven bulls) were re-introduced on 15 October 2013) as well as sixteen species of antelopes and over 250 species of birds, including the largest colony of Cape griffon vultures in the world (around 800 breeding pairs). The Matlabas River runs through the park. History The area now constituting Marakele was home to several iron-age settlements which are not yet open to public viewing. Prior to its foundation as a National Park, it was home to naturalist Eugene Marais Eugene may refer to: People and fictional ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Begging Behavior In Animals
Begging in animals is when an animal solicits being given resources by another animal. This is usually a young animal soliciting food from their parents, brood hosts or other adults. However, the resource is sometimes non-food related or may be solicited by adult animals. Begging behavior is most widely studied in birds, however, mammals, amphibians, and invertebrates perform begging displays. Generally in food solicitation, begging behavior is instinctive, although in some instances it is learned (e.g. pet cats and dogs). While the ultimate causation for begging is an increase in the animal's individual fitness, several theories have been proposed for how food begging evolved proximate causes including scramble competition, honest signalling of need, and cooperative begging by siblings. Various types of information such as nutritional status or immunocompetence can be transmitted with auditory and visual begging signals and the behavior can be modulated by several factors such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Birds Of Southern Africa
Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweight skeleton. Birds live worldwide and range in size from the bee hummingbird to the ostrich. There are about ten thousand living species, more than half of which are passerine, or "perching" birds. Birds have 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 loss of flight in some birds, including ratites, penguins, and diverse endemic island species. The digestive and respiratory systems of birds are also uniquely adapted for flight. Some bird species of aquatic environments, particularly seabirds and some waterbirds, have further evolved for swimming. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turdoides
''Turdoides'' is a genus of passerine birds in the laughingthrush family Leiothrichidae. The species are distributed across Africa and southern Asia and are typically fairly large, long-tailed birds which forage in noisy groups. The majority of species have drab brown or grey-brown plumage. Several species that were included in ''Turdoides'' in the past have been reassigned to ''Argya'' following a 2018 study that found multiple clades. The genus ''Turdoides'' was introduced in 1826 by the German physician Philipp Jakob Cretzschmar specifically for the white-headed babbler. The name combines the thrush genus ''Turdus'' with the Ancient Greek ''-oidēs'' meaning "resembling". Species The genus contains the following 19 species: * Brown babbler, ''Turdoides plebejus'' * Bare-cheeked babbler, ''Turdoides gymnogenys'' * Arrow-marked babbler, ''Turdoides jardineii'' * Scaly babbler, ''Turdoides squamulata'' * White-rumped babbler, ''Turdoides leucopygia'' * White-headed babbl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Handbook Of The Birds Of The World
The ''Handbook of the Birds of the World'' (HBW) is a multi-volume series produced by the Spanish publishing house Lynx Edicions in partnership with BirdLife International. It is the first handbook to cover every known living species of bird. The series was edited by Josep del Hoyo, Andrew Elliott, Jordi Sargatal and David A. Christie. All 16 volumes have been published. For the first time an animal class will have all the species illustrated and treated in detail in a single work. This has not been done before for any other group in the animal kingdom. Material in each volume is grouped first by family, with an introductory article on each family; this is followed by individual species accounts (taxonomy, subspecies and distribution, descriptive notes, habitat, food and feeding, breeding, movements, status and conservation, bibliography). In addition, all volumes except the first and second contain an essay on a particular ornithological theme. More than 200 renowned speci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zygosity
Zygosity (the noun, zygote, is from the Greek "yoked," from "yoke") () is the degree to which both copies of a chromosome or gene have the same genetic sequence. In other words, it is the degree of similarity of the alleles in an organism. Most eukaryotes have two matching sets of chromosomes; that is, they are diploid. Diploid organisms have the same loci on each of their two sets of homologous chromosomes except that the sequences at these loci may differ between the two chromosomes in a matching pair and that a few chromosomes may be mismatched as part of a chromosomal sex-determination system. If both alleles of a diploid organism are the same, the organism is homozygous at that locus. If they are different, the organism is heterozygous at that locus. If one allele is missing, it is hemizygous, and, if both alleles are missing, it is nullizygous. The DNA sequence of a gene often varies from one individual to another. These gene variants are called alleles. While some gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inbreeding Depression
Inbreeding depression is the reduced biological fitness which has the potential to result from inbreeding (the breeding of related individuals). Biological fitness refers to an organism's ability to survive and perpetuate its genetic material. Inbreeding depression is often the result of a population bottleneck. In general, the higher the genetic variation or gene pool within a breeding population, the less likely it is to suffer from inbreeding depression, though inbreeding and outbreeding depression can simultaneously occur. Inbreeding depression seems to be present in most groups of organisms, but varies across mating systems. Hermaphroditic species often exhibit lower degrees of inbreeding depression than outcrossing species, as repeated generations of selfing is thought to purge deleterious alleles from populations. For example, the outcrossing nematode (roundworm) ''Caenorhabditis remanei'' has been demonstrated to suffer severely from inbreeding depression, unlike its he ... [...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] |
Kleptoparasitism
Kleptoparasitism (etymologically, parasitism by theft) is a form of feeding in which one animal deliberately takes food from another. The strategy is evolutionarily stable when stealing is less costly than direct feeding, which can mean when food is scarce or when victims are abundant. Many kleptoparasites are arthropods, especially bees and wasps, but including some true flies, dung beetles, bugs, and spiders. Cuckoo bees are specialized kleptoparasites which lay their eggs either on the pollen masses made by other bees, or on the insect hosts of parasitoid wasps. They are an instance of Emery's rule, which states that insect social parasites tend to be closely related to their hosts. The behavior occurs, too, in vertebrates including birds such as skuas, which persistently chase other seabirds until they disgorge their food, and carnivorous mammals such as spotted hyenas and lions. Other species opportunistically indulge in kleptoparasitism. Strategy Kleptoparasitism is a fe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Group Size Measures
Many animals, including humans, tend to live in groups, herds, flocks, bands, packs, shoals, or colonies (hereafter: groups) of conspecific individuals. The size of these groups, as expressed by the number of people/etc in a group such as eight groups of nine people in each one, is an important aspect of their social environment. Group size tend to be highly variable even within the same species, thus we often need statistical measures to quantify group size and statistical tests to compare these measures between two or more samples. Group size measures are notoriously hard to handle statistically since groups sizes typically follow an aggregated (right-skewed) distribution: most groups are small, few are large, and a very few are very large. Statistical measures of group size roughly fall into two categories. Outsiders' view of group size * Group size is the number of individuals within a group; * Mean group size, the arithmetic mean of group sizes averaged over groups; * Co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Jardine (naturalist)
Sir William Jardine, 7th Baronet of Applegarth FRS FRSE FLS FSA (23 February 1800 – 21 November 1874) was a Scottish naturalist. He is known for his editing of a long series of natural history books, ''The Naturalist's Library''. Life and work Jardine was born on 23 February 1800 at 28 North Hanover Street in Edinburgh, the son of Sir Alexander Jardine, 6th baronet of Applegarth and his wife, Jane Maule. He was educated in both York and Edinburgh then studied medicine at Edinburgh University. From 1817 to 1821 he lodged with Rev Dr Andrew Grant at James Square, an arrangement made by his father. Grant was minister of St Andrew's Church on George Street. In his early years, aged only 25, he was elected a fellow of the Royal Society of Edinburgh his proposer being Sir David Brewster. He was a co-founder of the Berwickshire Naturalists' Club, and contributed to the founding of the Ray Society. He was "keenly addicted to field-sports, and a master equally of the rod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Avian Clutch Size
Clutch size refers to the number of eggs laid in a single brood by a nesting pair of birds. The numbers laid by a particular species in a given location are usually well defined by evolutionary trade-offs with many factors involved, including resource availability and energetic constraints. Several patterns of variation have been noted and the relationship between latitude and clutch size has been a topic of interest in avian reproduction and evolution. David Lack and R.E. Moreau were among the first to investigate the effect of latitude on the number of eggs per nest. Since Lack's first paper in the mid-1940s there has been extensive research on the pattern of increasing clutch size with increasing latitude. The proximate and ultimate causes for this pattern have been a subject of intense debate involving the development of ideas on group, individual, and gene-centric views of selection. Food limitation and nest predation hypotheses David Lack observed a direct relationship ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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