|
Orestias (fish)
''Orestias'' is a genus of pupfish. Older systematics classified them into the own family Orestiidae. They are found in lakes, rivers and springs in the Andean highlands of South America, and several species are considered threatened. They are egg-laying fish that feed on small animals and plant matter. The largest species can reach a total length of , but most remain far smaller. Their most characteristic feature is the absence of the ventral fin, although this is shared by a few other pupfish. Despite their moderate to small size, they are important to local fisheries and a few species are farmed. Several species are locally and colloquially known as ''carache''. The name of the genus is a reference to Orestes, a Greek mythological character who Valenciennes described as the "nymph of the mountains". Range and habitat ''Orestias'' is restricted to freshwater habitats at an altitude of in the Andes of central and southern Peru, western Bolivia, and northeastern Chile.Vila, M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Achille Valenciennes
Achille Valenciennes (9 August 1794 – 13 April 1865) was a French zoologist. Valenciennes was born in Paris, and studied under Georges Cuvier. His study of parasitic worms in humans made an important contribution to the study of parasitology. He also carried out diverse systematic classifications, linking fossil and current species. He worked with Cuvier on the 22-volume "'' Histoire Naturelle des Poissons''" (Natural History of Fish) (1828–1848), carrying on alone after Cuvier died in 1832. In 1832, he succeeded Henri Marie Ducrotay de Blainville (1777–1850) as chair of ''Histoire naturelle des mollusques, des vers et des zoophytes'' at the Muséum national d'histoire naturelle. Early in his career, he was given the task of classifying animals described by Alexander von Humboldt (1769–1859) during his travels in the American tropics (1799 to 1803), and a lasting friendship was established between the two men. He is the binomial authority for many species of fish, such a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lake Titicaca
Lake Titicaca (; es, Lago Titicaca ; qu, Titiqaqa Qucha) is a large freshwater lake in the Andes mountains on the border of Bolivia and Peru. It is often called the highest navigable lake in the world. By volume of water and by surface area, it is also the largest lake in South America.Grove, M. J., P. A. Baker, S. L. Cross, C. A. Rigsby and G. O. Seltzer 2003 Application of Strontium Isotopes to Understanding the Hydrology and Paleohydrology of the Altiplano, Bolivia-Peru. ''Palaeogeography, Palaeoclimatology, Palaeoecology'' 194:281-297. Lake Titicaca has a surface elevation of . The "highest lake" claim is generally considered to refer to commercial craft. Numerous smaller bodies of water (that are not considered lakes) around the world are at higher elevations. For many years, the largest vessel afloat on the lake was the 2,200-ton (2,425 U.S. tons), SS ''Ollanta''. Today, the largest vessel is most likely the similarly sized train barge/float ''Manco Capac'', operated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Introduced Species
An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived there by human activity, directly or indirectly, and either deliberately or accidentally. Non-native species can have various effects on the local ecosystem. Introduced species that become established and spread beyond the place of introduction are considered naturalized. The process of human-caused introduction is distinguished from biological colonization, in which species spread to new areas through "natural" (non-human) means such as storms and rafting. The Latin expression neobiota captures the characteristic that these species are ''new'' biota to their environment in terms of established biological network (e.g. food web) relationships. Neobiota can further be divided into neozoa (also: neozoons, sing. neozoon, i.e. animals) and neophyt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zooplankton
Zooplankton are the animal component of the planktonic community ("zoo" comes from the Greek word for ''animal''). Plankton are aquatic organisms that are unable to swim effectively against currents, and consequently drift or are carried along by currents in the ocean, or by currents in seas, lakes or rivers. Zooplankton can be contrasted with phytoplankton, which are the plant component of the plankton community ("phyto" comes from the Greek word for ''plant''). Zooplankton are heterotrophic (other-feeding), whereas phytoplankton are autotrophic (self-feeding). This means zooplankton cannot manufacture their own food but must eat other plants or animals instead — in particular they eat phytoplankton. Zooplankton are generally larger than phytoplankton, most are microscopic, but some (such as jellyfish) are macroscopic and can be seen with the naked eye. Many protozoans (single-celled protists that prey on other microscopic life) are zooplankton, including zooflagellates, fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Niche Differentiation
In ecology, niche differentiation (also known as niche segregation, niche separation and niche partitioning) refers to the process by which competing species use the environment differently in a way that helps them to coexist. The competitive exclusion principle states that if two species with identical niches (ecological roles) compete, then one will inevitably drive the other to extinction. This rule also states that two species cannot occupy the same exact niche in a habitat and coexist together, at least in a stable manner. When two species differentiate their niches, they tend to compete less strongly, and are thus more likely to coexist. Species can differentiate their niches in many ways, such as by consuming different foods, or using different areas of the environment. As an example of niche partitioning, several anole lizards in the Caribbean islands share common diets—mainly insects. They avoid competition by occupying different physical locations. Although these liz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Detritus
In biology, detritus () is dead particulate organic material, as distinguished from dissolved organic material. Detritus typically includes the bodies or fragments of bodies of dead organisms, and fecal material. Detritus typically hosts communities of microorganisms that colonize and decompose (i.e. remineralize) it. In terrestrial ecosystems it is present as leaf litter and other organic matter that is intermixed with soil, which is denominated " soil organic matter". The detritus of aquatic ecosystems is organic material that is suspended in the water and accumulates in depositions on the floor of the body of water; when this floor is a seabed, such a deposition is denominated "marine snow". Theory The corpses of dead plants or animals, material derived from animal tissues (e.g. molted skin), and fecal matter gradually lose their form due to physical processes and the action of decomposers, including grazers, bacteria, and fungi. Decomposition, the process by which or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chironomid
The Chironomidae (informally known as chironomids, nonbiting midges, or lake flies) comprise a family of nematoceran flies with a global distribution. They are closely related to the Ceratopogonidae, Simuliidae, and Thaumaleidae. Many species superficially resemble mosquitoes, but they lack the wing scales and elongated mouthparts of the Culicidae. The name Chironomidae stems from the Ancient Greek word ''kheironómos'', "a pantomimist". Common names and biodiversity This is a large taxon of insects; some estimates of the species numbers suggest well over 10,000 world-wide. Males are easily recognized by their plumose antennae. Adults are known by a variety of vague and inconsistent common names, largely by confusion with other insects. For example, chironomids are known as "lake flies" in parts of Canada and Lake Winnebago, Wisconsin, but "bay flies" in the areas near the bay of Green Bay, Wisconsin. They are called "sand flies", "muckleheads", "muffleheads", "Canadian so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladocera
The Diplostraca or Cladocera, commonly known as water fleas, are a superorder of small crustaceans that feed on microscopic chunks of organic matter (excluding some predatory forms). Over 1000 species have been recognised so far, with many more undescribed. The oldest fossils of diplostracans date to the Jurassic, though their modern morphology suggests that they originated substantially earlier, during the Paleozoic. Some have also adapted to a life in the ocean, the only members of Branchiopoda to do so, even if several anostracans live in hypersaline lakes. Most are long, with a down-turned head with a single median compound eye, and a carapace covering the apparently unsegmented thorax and abdomen. Most species show cyclical parthenogenesis, where asexual reproduction is occasionally supplemented by sexual reproduction, which produces resting eggs that allow the species to survive harsh conditions and disperse to distant habitats. Description They are mostly long, with t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amphipods
Amphipoda is an order of malacostracan crustaceans with no carapace and generally with laterally compressed bodies. Amphipods range in size from and are mostly detritivores or scavengers. There are more than 9,900 amphipod species so far described. They are mostly marine animals, but are found in almost all aquatic environments. Some 1,900 species live in fresh water, and the order also includes the terrestrial sandhoppers such as ''Talitrus saltator''. Etymology and names The name ''Amphipoda'' comes, via New Latin ', from the Greek roots 'on both/all sides' and 'foot'. This contrasts with the related Isopoda, which have a single kind of thoracic leg. Particularly among anglers, amphipods are known as ''freshwater shrimp'', ''scuds'', or ''sideswimmers''. Description Anatomy The body of an amphipod is divided into 13 segments, which can be grouped into a head, a thorax and an abdomen. The head is fused to the thorax, and bears two pairs of antennae and one pair of ses ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pelagic Zone
The pelagic zone consists of the water column of the open ocean, and can be further divided into regions by depth (as illustrated on the right). The word ''pelagic'' is derived . The pelagic zone can be thought of as an imaginary cylinder or water column between the surface of the sea and the bottom. Conditions in the water column change with depth: pressure increases; temperature and light decrease; salinity, oxygen, micronutrients (such as iron, magnesium and calcium) all change. Marine life is affected by bathymetry (underwater topography) such as the seafloor, shoreline, or a submarine seamount, as well as by proximity to the boundary between the ocean and the atmosphere at the ocean surface, which brings light for photosynthesis, predation from above, and wind stirring up waves and setting currents in motion. The pelagic zone refers to the open, free waters away from the shore, where marine life can swim freely in any direction unhindered by topographical constraints. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Totora (plant)
Totora (''Schoenoplectus californicus'' subsp. ''tatora'') is a subspecies of the giant bulrush sedge. It is found in South America, notably on Lake Titicaca, the middle coast of Peru and on Easter Island in the Pacific Ocean. The genus ''Schoenoplectus'' is closely related to ''Scirpus'' and sometimes included therein. This plant can reach a height of and commonly reaches .Iltis, A., and P. Mourguiart (1992). Higher Plants: Distribution and biomass. Pp. 242-253 in: Dejoux, C., eds. (1992). Lake Titicaca: a synthesis of limnological knowledge. The word totora comes from the Quechua language. The people of the mid-coast region of Peru have used totora to build their caballitos de totora, small rowed and straddled fishing vessels, for at least 3,000 years. The Uru people, an indigenous people predating the Inca civilisation, live on Lake Titicaca upon floating islands fashioned from this plant. The Uru people also use the totora plant to make boats (''balsas'') of the bundled d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
