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Mallards
The mallard () or wild duck (''Anas platyrhynchos'') is a dabbling duck that breeds throughout the temperate and subtropical Americas, Eurasia, and North Africa, and has been introduced species, introduced to New Zealand, Australia, Peru, Brazil, Uruguay, Argentina, Chile, Colombia, the Falkland Islands, and South Africa. This duck belongs to the subfamily Anatinae of the Anseriformes, waterfowl family Anatidae. Males have purple patches on their wings, while the females (hens or ducks) have mainly brown-speckled plumage. Both sexes have an area of white-bordered black or iridescent blue feathers called a speculum feathers, 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 Beak, bill is long. It is often slightly heavier than most other dabbling ducks, weighing . Mallards live in wetlands, eat water plants and small animals, and are social animal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Domesticated Duck
The domestic duck or domestic mallard (''Anas platyrhynchos domesticus'') is a subspecies of mallard that has been domesticated by humans and raised for meat, eggs, and down feathers. A few are also kept for show, as pets, or for their ornamental value. Almost all varieties of domesticated ducks, apart from the domestic Muscovy duck (''Cairina moschata''), are descended from the mallard. Domestication Whole-genome sequencing indicate that domestic ducks originate from a single domestication event of mallards during the Neolithic, followed by rapid selection for lineages favoring meat or egg production. They were likely domesticated in Southeast Asia (most likely Southern China) by the rice paddy-farming ancestors of modern Southeast Asians. The date of domestication is unknown due to the scarcity of archaeological records. They spread outwards from the region, first being mentioned in Han Chinese written records in central China by around 500 BC. Duck farming for both meat an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Domestic Duck
The domestic duck or domestic mallard (''Anas platyrhynchos domesticus'') is a subspecies of mallard that has been domesticated by humans and raised for meat, eggs, and down feathers. A few are also kept for show, as pets, or for their ornamental value. Almost all varieties of domesticated ducks, apart from the domestic Muscovy duck (''Cairina moschata''), are descended from the mallard. Domestication Whole-genome sequencing indicate that domestic ducks originate from a single domestication event of mallards during the Neolithic, followed by rapid selection for lineages favoring meat or egg production. They were likely domesticated in Southeast Asia (most likely Southern China) by the rice paddy-farming ancestors of modern Southeast Asians. The date of domestication is unknown due to the scarcity of archaeological records. They spread outwards from the region, first being mentioned in Han Chinese written records in central China by around 500 BC. Duck farming for both meat an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anatidae
The Anatidae are the biological family of water birds that includes ducks, geese, and swans. The family has a cosmopolitan distribution, occurring on all the world's continents except Antarctica. These birds are adapted for swimming, floating on the water surface, and in some cases diving in at least shallow water. The family contains around 174 species in 43 genera. (The magpie goose is no longer considered to be part of the Anatidae and is now placed in its own family, Anseranatidae.) They are generally herbivorous, and are monogamous breeders. A number of species undertake annual migrations. A few species have been domesticated for agriculture, and many others are hunted for food and recreation. Five species have become extinct since 1600, and many more are threatened with extinction. Description and ecology The ducks, geese, and swans are small- to large-sized birds with a broad and elongated general body plan. Diving species vary from this in being rounder. Extant s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Duck
Duck is the common name for numerous species of waterfowl in the family Anatidae. Ducks are generally smaller and shorter-necked than swans and geese, which are members of the same family. Divided among several subfamilies, they are a form taxon; they do not represent a monophyletic group (the group of all descendants of a single common ancestral species), since swans and geese are not considered ducks. Ducks are mostly aquatic birds, and may be found in both fresh water and sea water. Ducks are sometimes confused with several types of unrelated water birds with similar forms, such as loons or divers, grebes, gallinules and coots. Etymology The word ''duck'' comes from Old English 'diver', a derivative of the verb 'to duck, bend down low as if to get under something, or dive', because of the way many species in the dabbling duck group feed by upending; compare with Dutch and German 'to dive'. This word replaced Old English / 'duck', possibly to avoid confusion with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species Of Least Concern
A least-concern species is a species that has been categorized by the International Union for Conservation of Nature (IUCN) as evaluated as not being a focus of species 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 15636) in the IUCN database still use the code "LR/lc", which indicates they have not been re-evaluate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Union For Conservation Of Nature
The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natural resources. It is involved in data gathering and analysis, research, field projects, advocacy, and education. IUCN's mission is to "influence, encourage and assist societies throughout the world to conserve nature and to ensure that any use of natural resources is equitable and ecologically sustainable". Over the past decades, IUCN has widened its focus beyond conservation ecology and now incorporates issues related to sustainable development in its projects. IUCN does not itself aim to mobilize the public in support of nature conservation. It tries to influence the actions of governments, business and other stakeholders by providing information and advice and through building partnerships. The organization is best known to the wider pu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Invasive Species
An invasive species otherwise known as an alien is an introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, invasive species adversely affect habitats and bioregions, causing ecological, environmental, and/or economic damage. The term can also be used for native species that become harmful to their native environment after human alterations to its food webfor example the purple sea urchin (''Strongylocentrotus purpuratus'') which has decimated kelp forests along the northern California coast due to overharvesting of its natural predator, the California sea otter (''Enhydra lutris''). Since the 20th century, invasive species have become a serious economic, social, and environmental threat. Invasion of long-established ecosystems by organisms is a natural phenomenon, but human-facilitated introductions have greatly increased the rate, scale, and geographic range of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetic Pollution
Genetic pollution is a controversial term for uncontrolled gene flow into wild populations. It is defined as "the dispersal of contaminated altered genes from genetically engineered organisms to natural organisms, esp. by cross-pollination", but has come to be used in some broader ways. It is related to the population genetics concept of gene flow, and genetic rescue, which is genetic material intentionally introduced to increase the fitness of a population. It is called genetic pollution when it negatively impacts the fitness of a population, such as through outbreeding depression and the introduction of unwanted phenotypes which can lead to extinction. Conservation biologists and conservationists have used the term to describe gene flow from domestic, feral, and non-native species into wild indigenous species, which they consider undesirable. They promote awareness of the effects of introduced invasive species that may "''hybridize with native species, causing genetic polluti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anas Rubripes And Anas Platyrhynchos August 2008
''Anas'' is a genus of dabbling ducks. It includes the pintails, most teals, and the mallard and its close relatives. It formerly included additional species but following the publication of a molecular phylogenetic study in 2009 the genus was split into four separate genera. The genus now contains 31 living species. The name ''Anas'' is the Latin for "duck". Systematics The genus ''Anas'' was introduced by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his '' Systema Naturae''. ''Anas'' is the Latin word for a duck. The genus formerly included additional species. In 2009 a large molecular phylogentic study was published that compared mitochondrial DNA sequences from ducks, geese and swans in the family Anatidae. The results confirmed some of the conclusions of earlier smaller studies and indicated that the genus as then defined was non-monophyletic. Based on the results of this study, ''Anas'' was split into four proposed monophyletic genera with fiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carl Linnaeus
Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, the modern system of naming organisms. He is known as the "father of modern taxonomy". Many of his writings were in Latin; his name is rendered in Latin as and, after his 1761 ennoblement, as . Linnaeus was born in Råshult, the countryside of Småland, in southern Sweden. He received most of his higher education at Uppsala University and began giving lectures in botany there in 1730. He lived abroad between 1735 and 1738, where he studied and also published the first edition of his ' in the Netherlands. He then returned to Sweden where he became professor of medicine and botany at Uppsala. In the 1740s, he was sent on several journeys through Sweden to find and classify plants and animals. In the 1750s and 1760s, he continued to collect an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Precocial
In biology, altricial species are those in which the young are underdeveloped at the time of birth, but with the aid of their parents mature after birth. Precocial species are those in which the young are relatively mature and mobile from the moment of birth or hatching. Precocial species are normally nidifugous, meaning that they leave the nest shortly after birth or hatching. These categories form a continuum, without distinct gaps between them. Altriciality Etymology The word is derived from the Latin root ''alere'', meaning "to nurse, to rear, or to nourish" and indicates the need for young to be fed and taken care of for a long duration. By contrast, species whose young are immediately or quickly mobile are called ''precocial''. Precociality Etymology The word "precocial" is derived from the same root as ''precocious'', implying early maturity in both cases. Superprecociality Extremely precocial species are called "superprecocial". Examples are the megapode birds, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Systema Naturae
' (originally in Latin written ' with the ligature æ) is one of the major works of the Swedish botanist, zoologist and physician Carl Linnaeus (1707–1778) and introduced the Linnaean taxonomy. Although the system, now known as binomial nomenclature, was partially developed by the Bauhin brothers, Gaspard and Johann, Linnaeus was first to use it consistently throughout his book. The first edition was published in 1735. The full title of the 10th edition (1758), which was the most important one, was ' or translated: "System of nature through the three kingdoms of nature, according to classes, orders, genera and species, with characters, differences, synonyms, places". The tenth edition of this book (1758) is considered the starting point of zoological nomenclature. In 1766–1768 Linnaeus published the much enhanced 12th edition, the last under his authorship. Another again enhanced work in the same style and titled "'" was published by Johann Friedrich Gmelin between 1788 a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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