|
Podiceps Andinus
The Colombian grebe (''Podiceps andinus'') was a grebe found in the Bogotá wetlands on the Bogotá savanna in the Eastern Ranges of the Andes of Colombia. The species was still abundant in Lake Tota in 1945. The species has often been considered a subspecies of black-necked grebe (''P. nigricollis''), and is genetically nested within it; it differed from black-necked grebe most notably in having a reddish-brown (not black) foreneck, and more orangey-toned (rather than yellow) ear tufts. It was flightless. The decline of the Colombian grebe is attributed to wetland drainage, siltation, pesticide pollution, disruption by reed harvesting, hunting, competition, and predation of chicks by invasive introduced rainbow trout (''Oncorhynchus mykiss''). The primary reason was loss of habitat: drainage of wetlands and siltation resulted in higher concentrations of pollutants, causing eutrophication across Lake Tota. This destroyed the open, submergent pondweed (''Potamogeton'') vegetation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rodolphe Meyer De Schauensee
Rodolphe Meyer de Schauensee (; January 4, 1901 – April 24, 1984) was a Swiss-American ornithologist. Early life and education Meyer de Schauensee was born January 4, 1901 in Rome, Italy, one of two sons, to Baron Frederick Meyer de Schauensee and his American-born wife Matilda (née Toland; died 1932). His father was from a well-established Swiss aristocratic family originally from Lucerne that owned Schauensee Castle. In 1913, the family moved to the United States. He attended the Hoosac School in Hoosick, New York. He moved to Wynnewood, Pennsylvania in the 1920s. Career He was the curator of ornithology at the Academy of Natural Sciences in Philadelphia for nearly fifty years. He was particularly noted for his study of South American birds. He expanded the academy's collection of bird skins, taking part in collecting trips to Brazil, Thailand, Burma, southern Africa, the East Indies, and Guatemala. He wrote about the birds of South America, including the groundbreakin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Loss Of Habitat
Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease in biodiversity and species numbers. Habitat destruction is in fact the leading cause of biodiversity loss and species extinction worldwide. Humans contribute to habitat destruction through the use of natural resources, agriculture, industrial production and urbanization (urban sprawl). Other activities include mining, logging and trawling. Environmental factors can contribute to habitat destruction more indirectly. Geological processes, climate change, introduction of invasive species, ecosystem nutrient depletion, water and noise pollution are some examples. Loss of habitat can be preceded by an initial habitat fragmentation. Fragmentation and loss of habitat have become one of the most important topics of research in ecology as they ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extinct Birds Of South America
Extinction is the termination of an organism by the death of its last member. A taxon may become functionally extinct before the death of its last member if it loses the capacity to reproduce and recover. As a species' potential range may be very large, determining this moment is difficult, and is usually done retrospectively. This difficulty leads to phenomena such as Lazarus taxa, where a species presumed extinct abruptly "reappears" (typically in the fossil record) after a period of apparent absence. Over five billion species are estimated to have died out. It is estimated that there are currently around 8.7 million species of eukaryotes globally, possibly many times more if microorganisms are included. Notable extinct animal species include non-avian dinosaurs, saber-toothed cats, and mammoths. Through evolution, species arise through the process of speciation. Species become extinct when they are no longer able to survive in changing conditions or against superio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taxa Named By Rodolphe Meyer De Schauensee
In biology, a taxon (back-formation from ''taxonomy''; : taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and given a particular ranking, especially if and when it is accepted or becomes established. It is very common, however, for taxonomists to remain at odds over what belongs to a taxon and the criteria used for inclusion, especially in the context of rank-based (" Linnaean") nomenclature (much less so under phylogenetic nomenclature). If a taxon is given a formal scientific name, its use is then governed by one of the nomenclature codes specifying which scientific name is correct for a particular grouping. Initial attempts at classifying and ordering organisms (plants and animals) were presumably set forth in prehistoric times by hunter-gatherers, as suggested by the fairly sophisticated folk taxonomies. Much later, Aristotle, and later still ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Birds Described In 1959
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 common ostrich. There are over 11,000 living species and they are split into 44 orders. More than half are passerine or "perching" birds. Birds have wings 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 furth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Podiceps
''Podiceps'' is a genus of birds in the grebe family. The genus name comes from Latin , "rear-end" and ', "foot", and is a reference to the placement of a grebe's legs towards the rear of its body. It has representatives breeding in all continents except Antarctica. Some species are partially or entirely migratory, moving in winter to the coast or warmer climates. Most species are widespread and overall common, but three South American species each are restricted to a single country; two of them are seriously threatened and a third is already extinct. They breed in vegetated areas of freshwater lakes, nesting on the water's edge, since their legs are set too far back for easy walking. Usually two eggs are laid, and the striped young may be carried on the adult's back. All the genus are excellent swimmers and divers, and pursue their fish prey underwater. Adults have striking breeding plumage, with no difference between the sexes. In winter, the plumage is subdued whites and gr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elodea
''Elodea'' is a genus of eight species of aquatic plants often called the waterweeds described as a genus in 1803. Classified in the frog's-bit family ( Hydrocharitaceae), ''Elodea'' is native to the Americas and is also widely used as aquarium vegetation and laboratory demonstrations of cellular activities. It lives in fresh water. An older name for this genus is ''Anacharis'', which serves as a common name in North America. The introduction of some species of ''Elodea'' into waterways in parts of Europe, Australia, Africa, Asia, and New Zealand has created a significant problem and it is now considered a noxious weed in these areas. ;Species # '' Elodea bifoliata'' – Canada ( AB, SK), W United States ( OR + CA to NM + MN) # '' Elodea callitrichoides'' – Argentina, Uruguay # '' Elodea canadensis'' – most of United States + Canada # '' Elodea densa'' # '' Elodea granatensis'' – much of South America # '' Elodea heterostemon'' # '' Elodea najas'' # '' Elodea nu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monoculture
In agriculture, monoculture is the practice of growing one crop species in a field at a time. Monocultures increase ease and efficiency in planting, managing, and harvesting crops short-term, often with the help of machinery. However, monocultures are more susceptible to diseases or Pest (organism), pest outbreaks long-term due to localized reductions in biodiversity and nutrient depletion. Crop diversity can be added both in time, as with a crop rotation or sequence, or in space, with a polyculture or intercropping. Monocultures appear in contexts outside of agriculture and food production. Grass lawns are a common form of residential monocultures. Several monocultures, including single-species forest plantations, have become increasingly abundant throughout the tropics following market globalization, impacting local communities. Genetic monocultures refer to crops that have little to no genetic variation. This is achieved using cultivars, made through processes of propagation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potamogeton
''Potamogeton'' is a genus of aquatic, mostly freshwater, plants of the family Potamogetonaceae. Most are known by the common name pondweed, although many unrelated plants may be called pondweed, such as Canadian pondweed (''Elodea canadensis''). The genus name means "river neighbor", originating from the Greek ''potamos'' (river) and ''geiton'' (neighbor). Morphology ''Potamogeton'' species range from large (stems of 6 m or more) to very small (less than 10 cm). Height is strongly influenced by environmental conditions, particularly water depth. All species are technically perennial, but some species disintegrate in autumn to a large number of asexually produced resting buds called turions, which serve both as a means of overwintering and dispersal. Turions may be borne on the rhizome, on the stem, or on stolons from the rhizome. Most species, however, persist by perennial creeping rhizomes. In some cases the turions are the only means to differentiate species. The l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pondweed
Pondweed refers to many species and genera of aquatic plants and green algae: *''Potamogeton'', a diverse and worldwide genus *''Elodea'', found in North America *''Aponogeton'', in Africa, Asia and Australasia *''Groenlandia'', a genus of aquatic plants *''Stuckenia'', a genus of aquatic plants *Charales, an order of green algae {{Plant common name ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eutrophication
Eutrophication is a general term describing a process in which nutrients accumulate in a body of water, resulting in an increased growth of organisms that may deplete the oxygen in the water; ie. the process of too many plants growing on the surface of a river, lake, etc., often because chemicals that are used to help crops grow have been carried there by rain. Eutrophication may occur naturally or as a result of human actions. Manmade, or cultural, eutrophication occurs when sewage, Industrial wastewater treatment, industrial wastewater, fertilizer runoff, and other nutrient sources are released into the environment. Such nutrient pollution usually causes algal blooms and bacterial growth, resulting in the depletion of dissolved oxygen in water and causing substantial environmental degradation. Many policies have been introduced to combat eutrophication, including the United Nations Development Program (UNDP)'s sustainability development goals. Approaches for prevention and re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
