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Gens (behaviour)
In animal behaviour, a gens (pl. gentes) or host race is a lineage of a brood parasite species that inherits phenotypic traits adapted for a specific type of host, even though the whole parasite species uses a larger variety of hosts. Brood parasitism is particularly well-known in birds such as the common cuckoo, which lays its eggs in the nests of other birds and exploits the parental effort of the host bird to raise the parasitic offspring. Many species of avian brood parasite evolve to lay eggs that mimic their hosts' in appearance to reduce the chance that their eggs will be recognised and rejected by the hosts. Brood parasite species that evolve to have gentes are able to evolve close mimicry to a variety of host species with different egg appearances, but individual birds raised by different hosts can breed together without the risk of changing the specialized phenotypes of their eggs. A gens may be specialized to parasitise a few species of hosts with similar eggs, or one ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethology
Ethology is a branch of zoology that studies the behavior, behaviour of non-human animals. It has its scientific roots in the work of Charles Darwin and of American and German ornithology, ornithologists of the late 19th and early 20th century, including Charles Otis Whitman, Charles O. Whitman, Oskar Heinroth, and Wallace Craig. The modern discipline of ethology is generally considered to have begun during the 1930s with the work of the Dutch biologist Nikolaas Tinbergen and the Austrian biologists Konrad Lorenz and Karl von Frisch, the three winners of the 1973 Nobel Prize in Physiology or Medicine. Ethology combines laboratory and field science, with a strong relation to neuroanatomy, ecology, and evolutionary biology. Etymology The modern term ''ethology'' derives from the Greek language: wikt:ἦθος, ἦθος, ''ethos'' meaning "character" and , ''wikt:-logia, -logia'' meaning "the study of". The term was first popularized by the American entomologist William Mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animal Culture
Animal culture can be defined as the ability of non-human animals to learn and transmit behaviors through processes of social or cultural learning. Culture is increasingly seen as a process, involving the social transmittance of behavior among peers and between generations. It can involve the transmission of novel behaviors or regional variations that are independent of genetic or ecological factors. The existence of culture in non-humans has been a contentious subject, sometimes forcing researchers to rethink "what it is to be human". The notion of culture in other animals dates back to Aristotle in classical antiquity, and more recently to Charles Darwin, but the association of other animals' actions with the actual word 'culture' originated with Japanese primatology, primatologists' discoveries of socially-transmitted food behaviours in the 1940s. Evidence for animal culture is often based on studies of feeding behaviors, vocalizations, predator avoidance, mate selection, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shiny Cowbird
The shiny cowbird (''Molothrus bonariensis'') is a passerine bird in the New World family Icteridae. It breeds in most of South America except for dense forests and areas of high altitude such as mountains. Since 1900 the shiny cowbird's range has shifted northward, and it was recorded in the Caribbean islands as well as the United States, where it is found breeding in southern Florida. It is a bird associated with open habitats, including disturbed land from agriculture and deforestation. Adults are sexually dimorphic. Males are all black with a purple-blue iridescence. The female is smaller, with dull brown plumage that is sometimes paler on the underparts. Females of the species can be distinguished from the female brown-headed cowbird by their longer, finer bills and flatter heads. The shiny cowbird's diet consists mainly of insects, other arthropods and seeds, and they have been recorded foraging for grains in cattle troughs. Like most other cowbirds, it is an obligate bro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Screaming Cowbird
The screaming cowbird (''Molothrus rufoaxillaris'') is an obligate brood parasite belonging to the family Icteridae and is found in South America. It is also known commonly as the short billed cowbird.Fraga, R. M. (2011). Family Icteridae (New World Blackbirds). In Handbook of the Birds of the World, vol 16: Tanagers to New World Blackbirds (J. del Hoyo,. A. Elliot, and D. A. Christie, Editors). Lynx Edicions, Barcelona, Spain. pp. 684-807 Description The screaming cowbird has mildly iridescent black plumage; the lesser under-wing coverts are rufous. The female is slightly duller in colour than the male. The legs are black and the iris is reddish brown. Adult body length is 18–21 cm and mean adult weight is 58 g for males and 48 g for females.Davies, N. B. (2000). Cuckoos, Cowbirds and Other Cheats. Academic Press, London The call of the screaming cowbird was first described as "impetuous screaming notes"; however, a more useful description for field identifica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viduidae
The indigobirds, whydahs and cuckoo-finch make up the family Viduidae; they are small passerine birds native to Africa. These are Finch, finch-like species which usually have black or indigo predominating in their plumage. The birds named "whydahs"The yellow-mantled widowbird was the type species of its genus, and was originally named from the city of Ouidah in Benin. Nowadays the name whydah (i.e. Ouidah) is however applied to the long-tailed species of the Viduidae. have long or very long tails in the breeding male. All are obligate brood parasites, which lay their eggs in the nests of songbird species; most indigobirds use firefinches as hosts, whereas the paradise whydahs choose pytilias and the cuckoo-finch parasitises cisticolids. Unlike the cuckoos and honeyguides, the indigobirds and whydahs do not destroy the host's eggs. Typically, they lay 2–4 eggs in with those already present. The eggs of both the host and the victim are white, although the indigobird's are sli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cuckoo-finch
The cuckoo-finch (''Anomalospiza imberbis''), also known as the parasitic weaver or cuckoo weaver, is a small passerine bird now placed in the family Viduidae with the indigobirds and whydahs. It occurs in grassland in Africa south of the Sahara. The male is mainly yellow and green while the female is buff with dark streaks. They lay their eggs in the nests of other birds. Taxonomy The species was described in 1868 by the German ornithologist Jean Cabanis based on a specimen from East Africa, probably from the coast opposite Zanzibar. It was initially placed in the genus '' Crithagra'' but later moved to a genus of its own, ''Anomalospiza''. The name of the genus means "anomalous finch" with ''spiza'' being a Greek word for finch. The specific name ''imberbis'' comes from Latin and means "beardless". Its closest relatives are thought to be the indigobirds and whydahs of the genus '' Vidua''. These birds are now usually considered to form a family, Viduidae. Previously they were t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bird Nest
A bird nest is the spot in which a bird lays and Avian incubation, incubates its Bird egg, eggs and raises its young. Although the term popularly refers to a specific structures built by animals, structure made by the bird itself—such as the grassy cup nest of the American robin or Eurasian blackbird, or the elaborately woven hanging nest of the Montezuma oropendola or the village weaver—that is too restrictive a definition. For some species, a nest is simply a shallow depression made in sand; for others, it is the knot-hole left by a broken branch, a burrow dug into the ground, a chamber drilled into a tree, an enormous rotting pile of vegetation and earth, a shelf made of dried saliva or a mud dome with an entrance tunnel. The smallest bird nests are those of some hummingbirds, tiny cups which can be a mere across and high. At the other extreme, some nest mounds built by the dusky scrubfowl measure more than in diameter and stand nearly tall. The study of birds' nests ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greater Honeyguide
The greater honeyguide (''Indicator indicator'') is a bird in the family honeyguide, Indicatoridae, Floristic kingdom#Paleotropical Kingdom, paleotropical near passerine birds related to the woodpeckers. Its English language, English and scientific names refer to its habit of guiding people to bee colonies. Claims that it also guides non-human animals are disputed. The greater honeyguide is a resident breeder in sub-Saharan Africa. It is found in a variety of habitat (ecology), habitats that have trees, especially dry open woodland, but not in the West African rain forest, jungle. Description The greater honeyguide has bold white patches on the sides of the tail and is about long and weighs about . The male has a black throat, pink bill, dark grey-brown upperparts and white underparts. The wings are streaked whitish, and the shoulder patch is yellow. The female is duller, has a blackish bill, and her throat is black. Immature birds have olive-brown upperparts with a white rump ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene
In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. 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 non-coding genes. During gene expression (the synthesis of Gene product, RNA or protein from a gene), DNA is first transcription (biology), copied into RNA. RNA can be non-coding RNA, directly functional or be the intermediate protein biosynthesis, template for the synthesis of a protein. The transmission of genes to an organism's offspring, is the basis of the inheritance of phenotypic traits from one generation to the next. These genes make up different DNA sequences, together called a genotype, that is specific to every given individual, within the gene pool of the population (biology), population of a given species. The genotype, along with environmental and developmental factors, ultimately determines the phenotype ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autosome
An autosome is any chromosome that is not a sex chromosome. The members of an autosome pair in a diploid cell have the same morphology, unlike those in allosomal (sex chromosome) pairs, which may have different structures. The DNA in autosomes is collectively known as atDNA or auDNA. For example, humans have a diploid genome that usually contains 22 pairs of autosomes and one allosome pair (46 chromosomes total). The autosome pairs are labeled with numbers (1–22 in humans) roughly in order of their sizes in base pairs, while allosomes are labelled with their letters. By contrast, the allosome pair consists of two X chromosomes in females or one X and one Y chromosome in males. Unusual combinations XYY, XXY, XXX, XXXX, XXXXX or XXYY, among other irregular combinations, are known to occur and usually cause developmental abnormalities. Autosomes still contain sexual determination genes even though they are not sex chromosomes. For example, the SRY gene on the Y chromos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ZW Sex-determination System
The ZW sex-determination system is a chromosomal system that determines the sex of offspring in birds, some fish and crustaceans such as the giant river prawn, some insects (including butterflies and moths), the schistosome family of flatworms, and some reptiles, e.g. majority of snakes, lacertid lizards and monitors, including Komodo dragons. It is also present in some plants, where it has evolved independently on many occasions, characterizing at least 22% of plants with documented sex chromosomes. The letters Z and W are used to distinguish this system from the XY sex-determination system. In the ZW system, females have a pair of dissimilar ZW chromosomes, and males have two similar ZZ chromosomes. In contrast to the XY sex-determination system and the X0 sex-determination system, where the sperm determines the sex, in the ZW system, the ovum determines the sex of the offspring. Males are the homogametic sex (ZZ), while females are the heterogametic sex (ZW). The Z ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sex-linked
Sex linkage describes the sex-specific patterns of inheritance and expression when a gene is present on a sex chromosome (allosome) rather than a non-sex chromosome (autosome). Genes situated on the X-chromosome are thus termed X-linked, and are transmitted by both males and females, while genes situated on the Y-chromosome are termed Y-linked, and are transmitted by males only. As human females possess two X-chromosomes and human males possess one X-chromosome and one Y-chromosome, the phenotype of a sex-linked trait can differ between males and females due to the differential number of alleles (polymorphisms) possessed for a given gene. In humans, sex-linked patterns of inheritance are termed X-linked recessive, X-linked dominant and Y-linked. The inheritance and presentation of all three differ depending on the sex of both the parent and the child. This makes sex-linked patterns of inheritance characteristically different from autosomal dominance and recessiveness. This ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
