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Toucan2007
Toucans (, ) are Neotropical birds in the family Ramphastidae. They are most closely related to the Toucan barbets. They are brightly marked and have large, often colorful bills. The family includes five genera and over 40 different species. Toucans are arboreal and typically lay two to four white eggs in their nests. They make their nests in tree hollows and holes excavated by other animals such as woodpeckers—the toucan bill has very limited use as an excavation tool. When the eggs hatch, the young emerge completely naked, without any down. Toucans are resident breeders and do not migrate. Toucans are usually found in pairs or small flocks. They sometimes fence with their bills and wrestle, which scientists hypothesize they do to establish dominance hierarchies. In Africa and Asia, hornbills occupy the toucans' ecological niche, an example of convergent evolution. Taxonomy and systematics The name of this bird group is derived from the Tupi word ''tukana'' or the Gua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pleistocene
The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in 2009 by the International Union of Geological Sciences, the cutoff of the Pleistocene and the preceding Pliocene was regarded as being 1.806 million years Before Present (BP). Publications from earlier years may use either definition of the period. The end of the Pleistocene corresponds with the end of the last glacial period and also with the end of the Paleolithic age used in archaeology. The name is a combination of Ancient Greek () 'most' and (; Latinized as ) 'new'. The aridification and cooling trends of the preceding Neogene were continued in the Pleistocene. The climate was strongly variable depending on the glacial cycle, oscillating between cold Glacial period, glacial periods and warmer Interglacial, int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bird Egg
Bird eggs are laid by the females and range in quantity from one (as in condors) to up to seventeen (the grey partridge). Avian clutch size, Clutch size may vary latitudinally within a species. Some birds lay eggs even when the eggs have not been fertilized; it is not uncommon for pet owners to find their lone bird nesting on a clutch of infertile eggs, which are sometimes called wind-eggs. Anatomy All bird eggs contain the following components: * The embryo is the immature developing chick * The amnion is a membrane that initially covers the embryo and eventually fills with amniotic fluid, provides the embryo with protection against shock from movement * The allantois helps the embryo obtain oxygen and handles metabolic waste * The chorion, together with the amnion, forms the amniotic sac and encloses the amnion, vitellus, and the embryo * The Yolk, vitellus, or yolk, is the nutrient-bearing portion of the egg, containing most of its fat, minerals, and many of its proteins and bl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Portuguese Language
Portuguese ( or ) is a Western Romance language of the Indo-European language family originating from the Iberian Peninsula of Europe. It is the official language of Angola, Brazil, Cape Verde, Guinea-Bissau, Mozambique, Portugal and São Tomé and Príncipe, and has co-official language status in East Timor, Equatorial Guinea and Macau. Portuguese-speaking people or nations are known as Lusophone (). As the result of expansion during colonial times, a cultural presence of Portuguese speakers is also found around the world. Portuguese is part of the Iberian Romance languages, Ibero-Romance group that evolved from several dialects of Vulgar Latin in the medieval Kingdom of Galicia and the County of Portugal, and has kept some Gallaecian language, Celtic phonology. With approximately 250 million native speakers and 17 million second language speakers, Portuguese has approximately 267 million total speakers. It is usually listed as the List of languages by number of native speaker ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guarani Language
Guarani (Avañe'ẽ), also called Paraguayan Guarani, is a language of South America that belongs to the Tupi–Guarani branch of the Tupian languages, Tupian language family. It is one of the two official languages of Paraguay (along with Spanish language, Spanish), where it is spoken by the majority of the population, and where half of the rural population are monolingual speakers of the language. Variants of the language are spoken by communities in neighboring countries including parts of northeastern Argentina, southeastern Bolivia and southwestern Brazil. It is a second official language of the Provinces of Argentina, Argentine province of Corrientes Province, Corrientes since 2004 and in the Municipalities of Brazil, Brazilian city of Tacuru since 2010. Guarani is also one of the three official languages of Mercosur, alongside Spanish and Portuguese language, Portuguese. Guarani is one of the most widely spoken indigenous languages of the Americas, Native American langu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tupi Language
Old Tupi, Ancient Tupi or Classical Tupi () is a classical Tupian language which was spoken by the indigenous Tupi people of Brazil, mostly those who inhabited coastal regions in South and Southeast Brazil. In the words of Brazilian tupinologist Eduardo Navarro, "it is the classical indigenous language of Brazil, and the one which had the utmost importance to the cultural and spiritual formation of the country". Old Tupi belongs to the Tupi–Guarani language family, and has a written history spanning the 16th, 17th, and early 18th centuries. In the early colonial period, Tupi was used as a ''lingua franca'' throughout Brazil by Europeans and Amerindians, and had literary usage, but it was later suppressed almost to extinction. Today, its sole living descendant is the Nheengatu language. As the most important native language of Brazil, it is the origin of most city names of indigenous origin ( Pindamonhangaba, Ubatuba, Botucatu, Jacareí). It also names several plant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Convergent Evolution
Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last common ancestor of those groups. The cladistic term for the same phenomenon is Cladogram#Homoplasies, homoplasy. The recurrent evolution of flight is a classic example, as flying pterygota, insects, birds, pterosaurs, and bats have independently evolved the useful capacity of flight. Functionally similar features that have arisen through convergent evolution are ''analogous'', whereas ''homology (biology), homologous'' structures or traits have a common origin but can have dissimilar functions. Bird, bat, and pterosaur wings are analogous structures, but their forelimbs are homologous, sharing an ancestral state despite serving different functions. The opposite of convergence is divergent evolution, where related species evolve different trai ... [...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 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] |
Hornbill
Hornbills are birds found in tropical and subtropical Africa, Asia and Melanesia of the family Bucerotidae. They are characterized by a long, down-curved bill which is frequently brightly coloured and sometimes has a horny casque on the upper mandible. Hornbills have a two-lobed kidney. They are the only birds in which the first and second neck vertebrae (the atlas and axis respectively) are fused together; this probably provides a more stable platform for carrying the bill. The family is omnivorous, feeding on fruit and small animals. They are monogamous breeders nesting in natural cavities in trees and sometimes cliffs. A number of mainly insular species of hornbill with small ranges are threatened with extinction, mainly in Southeast Asia. In the Neotropical realm, toucans occupy the hornbills' ecological niche, an example of convergent evolution. Despite their close appearances, the two groups are not very closely related, with toucans being allied with the woodpeckers, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asia
Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which has long been home to the majority of the human population, was the site of many of the first civilisations. Its 4.7 billion people constitute roughly 60% of the world's population. Asia shares the landmass of Eurasia with Europe, and of Afro-Eurasia with both Europe and Africa. In general terms, it is bounded on the east by the Pacific Ocean, on the south by the Indian Ocean, and on the north by the Arctic Ocean. The border of Asia with Europe is a social constructionism, historical and cultural construct, as there is no clear physical and geographical separation between them. A commonly accepted division places Asia to the east of the Suez Canal separating it from Africa; and to the east of the Turkish straits, the Ural Mountains an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Africa
Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surface area.Sayre, April Pulley (1999), ''Africa'', Twenty-First Century Books. . With nearly billion people as of , it accounts for about of the world's human population. Demographics of Africa, Africa's population is the youngest among all the continents; the median age in 2012 was 19.7, when the worldwide median age was 30.4. Based on 2024 projections, Africa's population will exceed 3.8 billion people by 2100. Africa is the least wealthy inhabited continent per capita and second-least wealthy by total wealth, ahead of Oceania. Scholars have attributed this to different factors including Geography of Africa, geography, Climate of Africa, climate, corruption, Scramble for Africa, colonialism, the Cold War, and neocolonialism. Despite this lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bird Migration
Bird migration is a seasonal movement of birds between breeding and wintering grounds that occurs twice a year. It is typically from north to south or from south to north. Animal migration, Migration is inherently risky, due to predation and mortality. The Arctic tern holds the long-distance migration record for birds, travelling between Arctic breeding grounds and the Antarctic each year. Some species of Procellariiformes, tubenoses, such as albatrosses, circle the Earth, flying over the southern oceans, while others such as Manx shearwaters migrate between their northern breeding grounds and the southern ocean. Shorter migrations are common, while longer ones are not. The shorter migrations include altitudinal migrations on mountains, including the Andes and Himalayas. The timing of migration seems to be controlled primarily by changes in day length. Migrating birds navigate using celestial cues from the Sun and stars, the Earth's magnetic field, and mental maps. Histor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Down Feather
The down of birds is a layer of fine feathers found under the tougher exterior feathers. Very young birds are clad only in down. Powder down is a specialized type of down found only in a few groups of birds. Down is a fine thermal insulator and padding, used in goods such as Down jacket, jackets, bedding (duvets and featherbeds), pillows and sleeping bags. The discovery of feathers trapped in ancient amber suggests that some species of non-avian dinosaur likely possessed down-like feathers. Description and etymology The word ''down'' comes from the Old Norse word ''dúnn'', which had the same meaning as its modern equivalent. The down feather is considered to be the most "straightforward" of all feather types. It has a short or vestigial rachis (shaft), few barb (feather), barbs, and barbules that lack hooks. There are three types of down: natal down, body down and powder down. Natal down is the layer of down feathers that cover most birds at some point in their early developmen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
