White-fronted Woodpecker
The white-fronted woodpecker (''Melanerpes cactorum'') is a species of bird in the family Picidae. It is found mainly in Bolivia, Paraguay and Argentina. Its natural habitats are subtropical or tropical dry forests, subtropical or tropical dry shrubland, and subtropical or tropical high-altitude shrubland. Description The adult white-fronted woodpecker is about in length. The sexes are similar in appearance except for a small patch of red, not always visible, on the crown in males. The crown, nape and upper parts are glossy black, apart from a thin white line running from a white nape patch down the centre of the back. A black mask surrounds the eye and extends to the mantle. The upper side of the wings is bluish-black, boldly barred with white, and the underside is browner. The upper side of the tail is black with white markings and the underside is browner. The fore-crown and cheeks are white, and the chin and throat are white, yellow or buff. The breast and belly are some shad ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Alcide D'Orbigny
Alcide Charles Victor Marie Dessalines d'Orbigny (6 September 1802 – 30 June 1857) was a French naturalist who made major contributions in many areas, including zoology (including malacology), palaeontology, geology, archaeology and anthropology. D'Orbigny was born in Couëron ( Loire-Atlantique), the son of a ship's physician and amateur naturalist. The family moved to La Rochelle in 1820, where his interest in natural history was developed while studying the marine fauna and especially the microscopic creatures that he named "foraminiferans". In Paris he became a disciple of the geologist Pierre Louis Antoine Cordier (1777–1861) and Georges Cuvier. All his life, he would follow the theory of Cuvier and stay opposed to Lamarckism. South American era D'Orbigny travelled on a mission for the Paris Museum, in South America between 1826 and 1833. He visited Venezuela, Colombia, Ecuador, Peru, Bolivia, Chile, Argentina, Paraguay, and Brazil, and returned to France with an ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Iris (anatomy)
In humans and most mammals and birds, the iris (plural: ''irides'' or ''irises'') is a thin, annular structure in the eye, responsible for controlling the diameter and size of the pupil, and thus the amount of light reaching the retina. Eye color is defined by the iris. In optical terms, the pupil is the eye's aperture, while the iris is the diaphragm. Structure The iris consists of two layers: the front pigmented fibrovascular layer known as a stroma and, beneath the stroma, pigmented epithelial cells. The stroma is connected to a sphincter muscle (sphincter pupillae), which contracts the pupil in a circular motion, and a set of dilator muscles ( dilator pupillae), which pull the iris radially to enlarge the pupil, pulling it in folds. The sphincter pupillae is the opposing muscle of the dilator pupillae. The pupil's diameter, and thus the inner border of the iris, changes size when constricting or dilating. The outer border of the iris does not change size. The constricti ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Birds Of The Gran Chaco
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. Birds ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Melanerpes
''Melanerpes'' is a genus of woodpeckers of the family Picidae found in the New World. The 24 members of the genus are mostly colourful birds, conspicuously barred in black and white, with some red and yellow. Taxonomy The genus ''Melanerpes'' was introduced by the English ornithologist William John Swainson in 1832 to accommodate the red-headed woodpecker (''Melanerpes erythrocephalus''). The generic name combines the Ancient Greek ''melas'' meaning "black" with ''herpēs'' meaning "creeper". The genus forms part of the large tribe ''Melanerpini'', which also includes the North American sapsuckers in the genus '' Sphyrapicus'' and the monotypic genus ''Xiphidiopicus'' containing only the Cuban green woodpecker (''Xiphidiopicus percussus''). Characteristics Members of ''Melanerpes'' are small to medium-sized woodpeckers found exclusively in the New World. Some are West Indian endemics, and include species from Hispaniola, Puerto Rico, Jamaica and Guadeloupe; one subspecies, ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Least-concern Species
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]   |
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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]   |
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Savanna
A savanna or savannah is a mixed woodland-grassland (i.e. grassy woodland) ecosystem characterised by the trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of grasses. According to '' Britannica'', there exists four savanna forms; ''savanna woodland'' where trees and shrubs form a light canopy, ''tree savanna'' with scattered trees and shrubs, ''shrub savanna'' with distributed shrubs, and ''grass savanna'' where trees and shrubs are mostly nonexistent.Smith, Jeremy M.B.. "savanna". Encyclopedia Britannica, 5 Sep. 2016, https://www.britannica.com/science/savanna/Environment. Accessed 17 September 2022. Savannas maintain an open canopy despite a high tree density. It is often believed that savannas feature widely spaced, scattered trees. However, in many savannas, tree densities are higher and trees are more regularly spaced than in for ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Gran Chaco
The Gran Chaco or Dry Chaco is a sparsely populated, hot and semiarid lowland natural region of the Río de la Plata basin, divided among eastern Bolivia, western Paraguay, northern Argentina, and a portion of the Brazilian states of Mato Grosso and Mato Grosso do Sul, where it is connected with the Pantanal region. This land is sometimes called the Chaco Plain. Toponymy The name Chaco comes from a word in Quechua, an indigenous language from the Andes and highlands of South America. The Quechua word ''chaqu'' meaning "hunting land" comes probably from the rich variety of animal life present throughout the entire region. Geography The Gran Chaco is about 647,500 km² (250,000 sq mi) in size, though estimates differ. It is located west of the Paraguay River and east of the Andes, and is mostly an alluvial sedimentary plain shared among Paraguay, Bolivia, and Argentina. It stretches from about 17 to 33°S latitude and between 65 and 60°W longitude, though estimate ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Shrubland
Shrubland, scrubland, scrub, brush, or bush is a plant community characterized by vegetation dominated by shrubs, often also including grasses, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity. It may be the mature vegetation type in a particular region and remain stable over time, or a transitional community that occurs temporarily as the result of a disturbance, such as fire. A stable state may be maintained by regular natural disturbance such as fire or browsing. Shrubland may be unsuitable for human habitation because of the danger of fire. The term was coined in 1903. Shrubland species generally show a wide range of adaptations to fire, such as heavy seed production, lignotubers, and fire-induced germination. Botanical structural form In botany and ecology a shrub is defined as a much-branched woody plant less than 8 m high and usually with many stems. Tall shrubs are mostly 2–8 m high, small shrubs 1–2 m high and su ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Bird
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. B ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Forest
A forest is an area of land dominated by trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' Food and Agriculture Organization (FAO) defines a forest as, "Land spanning more than 0.5 hectares with trees higher than 5 meters and a canopy cover of more than 10 percent, or trees able to reach these thresholds ''in situ''. It does not include land that is predominantly under agricultural or urban use." Using this definition, '' Global Forest Resources Assessment 2020'' (FRA 2020) found that forests covered , or approximately 31 percent of the world's land area in 2020. Forests are the predominant terrestrial ecosystem of Earth, and are found around the globe. More than half of the world's forests are found in only five countries (Brazil, Canada, China, Russia, and the United States). The largest share of forests (45 percent) are in th ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Habitat
In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical manifestation of its ecological niche. Thus "habitat" is a species-specific term, fundamentally different from concepts such as environment or vegetation assemblages, for which the term "habitat-type" is more appropriate. The physical factors may include (for example): soil, moisture, range of temperature, and light intensity. Biotic factors will include the availability of food and the presence or absence of predators. Every species has particular habitat requirements, with habitat generalist species able to thrive in a wide array of environmental conditions while habitat specialist species requiring a very limited set of factors to survive. The habitat of a species is not necessarily found in a geographical area, it can be the interior ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |