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Green-winged Teal
The green-winged teal (''Anas carolinensis'') or American teal is a common and widespread duck that breeds in the northern areas of North America except on the Aleutian Islands. It was considered conspecific with the Eurasian teal (''A. crecca'') for some time, but the two have since been split into separate species. The American Ornithological Society continues to debate this determination; however, nearly all other authorities consider it distinct based on behavioral, morphological, and molecular evidence. The scientific name is from Latin ''Anas'', "duck" and ''carolinensis'', "of Carolina". This dabbling duck is strongly migratory and winters far south of its breeding range. It is highly gregarious outside of the breeding season and will form large flocks. In flight, the fast, twisting flocks resemble waders. Taxonomy The green-winged teal was formally described in 1789 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johann Friedrich Gmelin
Johann Friedrich Gmelin (8 August 1748 – 1 November 1804) was a German natural history, naturalist, chemist, botanist, entomologist, herpetologist, and malacologist. Education Johann Friedrich Gmelin was born as the eldest son of Philipp Friedrich Gmelin in 1748 in Tübingen. He studied medicine under his father at University of Tübingen and graduated with a Master's degree in 1768, with a thesis entitled: ', defended under the presidency of Ferdinand Christoph Oetinger, whom he thanks with the words '. Career In 1769, Gmelin became an adjunct professor of medicine at University of Tübingen. In 1773, he became professor of philosophy and adjunct professor of medicine at University of Göttingen. He was promoted to full professor of medicine and professor of chemistry, botany, and mineralogy in 1778. He died in 1804 in Göttingen and is buried there in the Albanifriedhof, Albani cemetery with his wife Rosine Louise Gmelin (1755–1828, née Schott). Johann Friedrich Gm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Binomial Nomenclature
In taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin grammatical forms, although they can be based on words from other languages. Such a name is called a binomial name (often shortened to just "binomial"), a binomen, name, or a scientific name; more informally, it is also called a Latin name. In the International Code of Zoological Nomenclature (ICZN), the system is also called nomenclature, with an "n" before the "al" in "binominal", which is a typographic error, meaning "two-name naming system". The first part of the name – the '' generic name'' – identifies the genus to which the species belongs, whereas the second part – the specific name or specific epithet – distinguishes the species within the genus. For example, modern humans belong to the genus ''Homo'' and within this genus to the species ''Hom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mexico
Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundary, maritime boundaries with the Pacific Ocean to the west, the Caribbean Sea to the southeast, and the Gulf of Mexico to the east. Mexico covers 1,972,550 km2 (761,610 sq mi), and is the List of countries by area, thirteenth-largest country in the world by land area. With a population exceeding 130 million, Mexico is the List of countries by population, tenth-most populous country in the world and is home to the Hispanophone#Countries, largest number of native Spanish speakers. Mexico City is the capital and List of cities in Mexico, largest city, which ranks among the List of cities by population, most populous metropolitan areas in the world. Human presence in Mexico dates back to at least 8,000 BC. Mesoamerica, considered a cradle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Least Concern
A least-concern species is a species that has been evaluated and categorized by the International Union for Conservation of Nature (IUCN) as not being a focus of wildlife conservation because the specific species is still plentiful in the wild. They do not qualify as threatened, near threatened, or (before 2001) conservation dependent. Species cannot be assigned the "Least Concern" category unless they have had their population status evaluated. That is, adequate information is needed to make a direct, or indirect, assessment of its risk of extinction based on its distribution or population status. Evaluation Since 2001 the category has had the abbreviation "LC", following the IUCN 2001 Categories & Criteria (version 3.1). Before 2001 "least concern" was a subcategory of the " Lower Risk" category and assigned the code "LR/lc" or lc. Around 20% of least concern taxa (3261 of 15,636) in the IUCN database still use the code "LR/lc", which indicates they have not been re- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conservation Status
The conservation status of a group of organisms (for instance, a species) indicates whether the group still exists and how likely the group is to become extinct in the near future. Many factors are taken into account when assessing conservation status: not simply the number of individuals remaining, but the overall increase or decrease in the population over time, breeding success rates, and known threats. Various systems of conservation status are in use at international, multi-country, national and local levels, as well as for consumer use such as sustainable seafood advisory lists and certification. The two international systems are by the International Union for Conservation of Nature (IUCN) and The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). International systems IUCN Red List of Threatened Species The IUCN Red List of Threatened Species by the International Union for Conservation of Nature is the best known worldwide conse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taiga
Taiga or tayga ( ; , ), also known as boreal forest or snow forest, is a biome characterized by coniferous forests consisting mostly of pines, spruces, and larches. The taiga, or boreal forest, is the world's largest land biome. In North America, it covers most of inland Canada, Alaska, and parts of the northern contiguous United States. In Eurasia, it covers most of Sweden, Finland, much of Russia from Karelia in the west to the Pacific Ocean (including much of Siberia), much of Norway and Estonia, some of the Scottish Highlands, some lowland/coastal areas of Iceland, and areas of northern Kazakhstan, northern Mongolia, and northern Japan (on the island of Hokkaido). The principal tree species, depending on the length of the growing season and summer temperatures, vary across the world. The taiga of North America is mostly spruce; Scandinavian and Finnish taiga consists of a mix of spruce, pines and birch; Russian taiga has spruces, pines and larches depending on the reg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mallard
The mallard () or wild duck (''Anas platyrhynchos'') is a dabbling duck that breeds throughout the temperate and subtropical Americas, Eurasia, and North Africa. It has been introduced to New Zealand, Australia, Peru, Brazil, Uruguay, Argentina, Chile, Colombia, the Falkland Islands, and South Africa. Belonging to the subfamily Anatinae of the waterfowl family Anatidae, mallards live in wetlands, eat water plants and small animals, and are social animals preferring to congregate in groups or flocks of varying sizes. Males (drakes) have green heads, while the females (hens) have mainly brown-speckled plumage. Both sexes have an area of white-bordered black or iridescent purple or blue feathers called a speculum on their wings; males especially tend to have blue speculum feathers. The mallard is long, of which the body makes up around two-thirds the length. The wingspan is and the bill is long. It is often slightly heavier than most other dabbling ducks, weighing . T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Feather
Feathers are epidermal growths that form a distinctive outer covering, or plumage, on both avian (bird) and some non-avian dinosaurs and other archosaurs. They are the most complex integumentary structures found in vertebrates and an example of a complex evolutionary novelty. They are among the characteristics that distinguish the extant birds from other living groups. Although feathers cover most of the bird's body, they arise only from certain well-defined tracts on the skin. They aid in flight, thermal insulation, and waterproofing. In addition, coloration helps in communication and protection. The study of feathers is called plumology (or plumage science). People use feathers in many ways that are practical, cultural, and religious. Feathers are both soft and excellent at trapping heat; thus, they are sometimes used in high-class bedding, especially pillows, blankets, and mattresses. They are also used as filling for winter clothing and outdoor bedding, such as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eurasia
Eurasia ( , ) is a continental area on Earth, comprising all of Europe and Asia. According to some geographers, Physical geography, physiographically, Eurasia is a single supercontinent. The concept of Europe and Asia as distinct continents dates back to classical antiquity, antiquity, but their borders have historically been subject to change. For example, the ancient Greeks originally included Africa in Asia but classified Europe as separate land. Eurasia is connected to Africa at the Suez Canal, and the two are sometimes combined to describe the largest contiguous landmass on Earth, Afro-Eurasia. History Eurasia has been the host of many ancient civilizations, including those based in Mesopotamia, Egypt, the Indus Valley and China. In the Axial Age (mid-first millennium BCE), a continuous belt of civilizations stretched through the Eurasian Subtropics, subtropical zone from the Atlantic to the Pacific. This belt became the mainstream of world history for two millennia. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Speculum Feathers
The speculum is a patch, often distinctly coloured, on the secondary wing feathers, or ''remiges'', of some birds. Examples of the colour(s) of the speculum in a number of ducks are: * Common teal and green-winged teal: Iridescent green edged with buff. * Blue-winged teal: Iridescent green. The species' common name comes from the sky-blue wing coverts. * Crested duck and bronze-winged duck: Iridescent purple-bronze, edged white. * Pacific black duck: Iridescent green, edged light buff. * Mallard: Iridescent purple-blue with white edges. * American black duck: Iridescent violet bordered in black and may have a thin white trailing edge. * Northern pintail: Iridescent green in male and brown in female, both are white on trailing edge. * Gadwall: Both sexes have white inner secondaries. * Yellow-billed duck: Iridescent green or blue, bordered white. Bright wing speculums are also known from a number of other birds; among them are several parrots from the genus Gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subspecies
In Taxonomy (biology), biological classification, subspecies (: subspecies) is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (Morphology (biology), morphology), but that can successfully interbreed. Not all species have subspecies, but for those that do there must be at least two. Subspecies is abbreviated as subsp. or ssp. and the singular and plural forms are the same ("the subspecies is" or "the subspecies are"). In zoology, under the International Code of Zoological Nomenclature, the subspecies is the only taxonomic rank below that of species that can receive a name. In botany and mycology, under the International Code of Nomenclature for algae, fungi, and plants, other infraspecific name, infraspecific ranks, such as variety (botany), variety, may be named. In bacteriology and virology, under standard International Code of Nomenclature of Prokaryotes, bacterial nomenclature and virus clas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
