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American Cliff Swallow
The cliff swallow or American cliff swallow (''Petrochelidon pyrrhonota'') is a member of the passerine bird family Swallow, Hirundinidae, the swallows and martins. The generic name ''Petrochelidon'' is derived from the Ancient Greek meaning "stone" and () "swallow", and the specific name ''pyrrhonota'' comes from ''purrhos'' meaning "flame-coloured" and ''-notos'' "-backed". Cliff swallows are extremely social songbirds that can be found in large nesting colonies reaching over 2,000 Bird nest, nests. They are frequently seen flying overhead in large Flocking (behavior), flocks during Bird migration, migration, gracefully foraging over fields for flying insects or perching tightly together on a wire preening under the sun. Cliff swallows build gourd-shaped nests made from mud with small entrance holes. They build their nests tightly together, on top of one another, under bridges or alongside mountain cliffs. Living in large populations, these aerial insectivores use extensive ...
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Louis Pierre Vieillot
Louis Pierre Vieillot (10 May 1748, Yvetot – 24 August 1830, Sotteville-lès-Rouen) was a French ornithologist. Vieillot is the author of the first scientific descriptions and Linnaean names of a number of birds, including species he collected himself in the West Indies and North America and South American species discovered but not formally named by Félix de Azara and his translator Sonnini de Manoncourt. He was among the first ornithologists to study changes in plumage and one of the first to study live birds. At least 77 of the genera erected by Vieillot are still in use. Biography Vieillot was born in Yvetot. He represented his family's business interests in Saint-Domingue (Haiti) on Hispaniola, but fled to the United States during the Haitian rebellions that followed the French Revolution. On Buffon's advice, he collected material for the , the first two volumes of which were published in France beginning in 1807. Vieillot returned to France for the last time in 1798, whe ...
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Seminal Vesicle
The seminal vesicles (also called vesicular glands or seminal glands) are a pair of convoluted tubular accessory glands that lie behind the urinary bladder of male mammals. They secrete fluid that largely composes the semen. The vesicles are 5–10 cm in size, 3–5 cm in diameter, and are located between the bladder and the rectum. They have multiple outpouchings, which contain secretory glands, which join together with the vasa deferentia at the ejaculatory ducts. They receive blood from the vesiculodeferential artery, and drain into the vesiculodeferential veins. The glands are lined with column-shaped and cuboidal cells. The vesicles are present in many groups of mammals, but not marsupials, monotremes or carnivores. Inflammation of the seminal vesicles is called seminal vesiculitis and most often is due to bacterial infection as a result of a sexually transmitted infection or following a surgical procedure. Seminal vesiculitis can cause pain in the lower abdo ...
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Canada
Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of countries and dependencies by area, second-largest country by total area, with the List of countries by length of coastline, world's longest coastline. Its Canada–United States border, border with the United States is the world's longest international land border. The country is characterized by a wide range of both Temperature in Canada, meteorologic and Geography of Canada, geological regions. With Population of Canada, a population of over 41million people, it has widely varying population densities, with the majority residing in List of the largest population centres in Canada, urban areas and large areas of the country being sparsely populated. Canada's capital is Ottawa and List of census metropolitan areas and agglomerations in Canada, ...
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Infrastructure
Infrastructure is the set of facilities and systems that serve a country, city, or other area, and encompasses the services and facilities necessary for its economy, households and firms to function. Infrastructure is composed of public and private physical structures such as roads, railways, bridges, airports, public transit systems, tunnels, water supply, sewers, electrical grids, and telecommunications (including Internet connectivity and broadband access). In general, infrastructure has been defined as "the physical components of interrelated systems providing commodities and services essential to enable, sustain, or enhance societal living conditions" and maintain the surrounding environment. Especially in light of the massive societal transformations needed to mitigate and adapt to climate change, contemporary infrastructure conversations frequently focus on sustainable development and green infrastructure. Acknowledging this importance, the international co ...
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Adaptation
In biology, adaptation has three related meanings. Firstly, it is the dynamic evolutionary process of natural selection that fits organisms to their environment, enhancing their evolutionary fitness. Secondly, it is a state reached by the population during that process. Thirdly, it is a phenotypic trait or adaptive trait, with a functional role in each individual organism, that is maintained and has evolved through natural selection. Historically, adaptation has been described from the time of the ancient Greek philosophers such as Empedocles and Aristotle. In 18th and 19th-century natural theology, adaptation was taken as evidence for the existence of a deity. Charles Darwin and Alfred Russel Wallace proposed instead that it was explained by natural selection. Adaptation is related to biological fitness, which governs the rate of evolution as measured by changes in allele frequencies. Often, two or more species co-adapt and co-evolve as they develop adaptations tha ...
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North America
North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Caribbean Sea, and to the south and west by the Pacific Ocean. The region includes Middle America (Americas), Middle America (comprising the Caribbean, Central America, and Mexico) and Northern America. North America covers an area of about , representing approximately 16.5% of Earth's land area and 4.8% of its total surface area. It is the third-largest continent by size after Asia and Africa, and the list of continents and continental subregions by population, fourth-largest continent by population after Asia, Africa, and Europe. , North America's population was estimated as over 592 million people in list of sovereign states and dependent territories in North America, 23 independent states, or about 7.5% of the world's popula ...
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Cave Swallow
The cave swallow (''Petrochelidon fulva'') is a medium-sized, squarish-tailed swallow belonging to the same genus as the more familiar and widespread cliff swallow of North America. The cave swallow, also native to the Americas, nests and roosts primarily in caves and sinkholes. Cave swallows are found in Mexico and the Greater Antilles, with fall and winter vagrants reaching the east and Gulf Coasts of the U.S. Breeding colonies occur in south-eastern New Mexico, Texas, Florida, the Greater Antilles, portions of southern Mexico, and along the west coast of South America. Five subspecies are currently recognized according to '' Birds of North America'', three occurring in North America and two in South America.West, S. (1995). Cave Swallow (Hirundo fulva). In The Birds of North America, No. 141 (A. Poole and F. Gill, eds.). The Academy of Natural Sciences, Philadelphia, and The American Ornithologists' Union, Washington, D.C. Description The cave swallow measures 12 to 14  ...
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Songbird
A songbird is a bird belonging to the suborder Passeri of the perching birds (Passeriformes). Another name that is sometimes seen as the scientific or vernacular name is Oscines, from Latin ''oscen'', "songbird". The Passeriformes contains 5,000 or so speciesEdwards, Scott V. and John Harshman. 2013. Passeriformes. Perching Birds, Passerine Birds. Version 06 February 2013 (under construction). http://tolweb.org/Passeriformes/15868/2013.02.06 in The Tree of Life Web Project, http://tolweb.org/ ccessed 2017/12/11 found all over the world, in which the vocal organ typically is developed in such a way as to produce a diverse and elaborate bird song. Songbirds form one of the two major lineages of extant perching birds (~4,000 species), the other being the Tyranni (~1,000 species), which are most diverse in the Neotropics and absent from many parts of the world. The Tyranni have a simpler syrinx musculature, and while their vocalizations are often just as complex and striking as ...
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Anisodactyly
In biology, dactyly is the arrangement of digits (fingers and toes) on the hands, feet, or sometimes wings of a tetrapod animal. The term is derived from the Greek word () meaning "finger." Sometimes the suffix "-dactylia" is used. The derived adjectives end with "-dactyl" or "-dactylous." As a normal feature Pentadactyly Pentadactyly (from Greek "five") is the condition of having five digits on each limb. It is traditionally believed that all living tetrapods are descended from an ancestor with a pentadactyl limb, although many species have now lost or transformed some or all of their digits by the process of evolution. However, this viewpoint was challenged by Stephen Jay Gould in his 1991 essay "Eight (or Fewer) Little Piggies," where he pointed out polydactyly in early tetrapods and described the specializations of digit reduction. Despite the individual variations listed below, the relationship is to the original five-digit model. In reptiles, the limbs are pentadacty ...
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Passerine
A passerine () is any bird of the order Passeriformes (; from Latin 'sparrow' and '-shaped') which includes more than half of all bird species. Sometimes known as perching birds, passerines generally have an anisodactyl arrangement of their toes (three pointing forward and one back), which facilitates perching. With more than 140 families and some 6,500 identified species, Passeriformes is the largest order of birds and one of the most diverse clades of terrestrial vertebrates, representing 60% of birds.Ericson, P.G.P. et al. (2003Evolution, biogeography, and patterns of diversification in passerine birds ''J. Avian Biol'', 34:3–15.Selvatti, A.P. et al. (2015"A Paleogene origin for crown passerines and the diversification of the Oscines in the New World" ''Molecular Phylogenetics and Evolution'', 88:1–15. Passerines are divided into three suborders: New Zealand wrens; Suboscines, primarily found in North and South America; and songbirds. Passerines originated in the ...
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Phylogenetics
In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical data and observed heritable traits of DNA sequences, protein amino acid sequences, and morphology. The results are a phylogenetic tree—a diagram depicting the hypothetical relationships among the organisms, reflecting their inferred evolutionary history. The tips of a phylogenetic tree represent the observed entities, which can be living taxa or fossils. A phylogenetic diagram can be rooted or unrooted. A rooted tree diagram indicates the hypothetical common ancestor of the taxa represented on the tree. An unrooted tree diagram (a network) makes no assumption about directionality of character state transformation, and does not show the origin or "root" of the taxa in question. In addition to their use for inferring phylogenetic pa ...
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Petrochelidon Pyrrhonota 1894
''Petrochelidon'' is a genus of birds known as cliff-nesting swallows. The genus name ''Petrochelidon'' is from the Greek words ''petra'', "rock", and ''khelidon'', "swallow". The genus includes all of the five species of birds commonly called cliff swallow, and contains the following species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...: Species in taxonomic order The genus contains ten species: References External links''Petrochelidon'' at Animal Diversity Hirundinidae Bird genera {{Hirundinidae-stub ...
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