|
Rainbow Darter
The rainbow darter (''Etheostoma caeruleum'') is a small species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is native to North America where it is found in small, fast-moving streams and small to medium-sized rivers. It grows to in length. The species is very sensitive to pollution and silt, staying in clean, pollution-free water. The rainbow darter is easily identified by three dark spots on the back, and blue and orange in the dorsal and anal fins. Life The rainbow darter lives in clean, rocky riffles from March through June. It has a lifespan of about 4 years. The males can grow up to 48 mm long, while the largest female reaches just under 43 mm. The male form is resplendent in bright oranges and iridescent blue spots, stripes, and checks. Distribution The rainbow darter is a small, benthic freshwater fish found in many creeks and small to m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
David Humphreys Storer
David Humphreys Storer (March 26, 1804—September 10, 1891) was an American physician and naturalist. He served as dean of the Faculty of Medicine at Harvard Medical School from 1855–1864, and published on the reptiles and fishes of New England. He was elected as a member of the American Philosophical Society in 1872. The colubrid snake genus '' Storeria'' is named in his honor.Beolens, Bo; Watkins, Michael; Grayson, Michael (2011). ''The Eponym Dictionary of Reptiles''. Baltimore: Johns Hopkins University Press. xiii + 296 pp. . ("Storer", p. 255). Selected bibliography *Storer, David Humphreys; Peabody, William Bourne Oliver (1839). ''Reports on the Fishes, Reptiles and Birds of Massachusetts''. Boston: Dutton and Wentworth, State Printers. *Storer DH (1846)"A Synopsis of the Fishes of North America" ''Memoirs of the American Academy of Arts and Sciences'' 2: 253–550. *Storer DH (1853)"A History of the Fishes of Massachusetts" ''Memoirs of the American Academy of Arts a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brackish Water
Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater (salt water) and fresh water together, as in estuaries, or it may occur in brackish fossil aquifers. The word comes from the Middle Dutch root '' brak''. Certain human activities can produce brackish water, in particular civil engineering projects such as dikes and the flooding of coastal marshland to produce brackish water pools for freshwater prawn farming. Brackish water is also the primary waste product of the salinity gradient power process. Because brackish water is hostile to the growth of most terrestrial plant species, without appropriate management it is damaging to the environment (see article on shrimp farms). Technically, brackish water contains between 0.5 and 30 grams of salt per litre—more often expressed as 0.5 to 30 parts per thousand (‰), which is a specific gr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Etheostoma
''Etheostoma'' is a genus of small freshwater fish in the family Percidae native to North America. Most are restricted to the United States, but species are also found in Canada and Mexico. They are commonly known as darters, although the term "darter" is shared by several other genera. Many can produce alarm pheromones that serve to warn nearby fish in case of an attack.Smith, R.J.F. (1992): Alarm signals in fishes. ''Reviews in Fish Biology and Fisheries, 2 (1): 33-63.'' Species The 157 recognized species in this genus are: * ''Etheostoma acuticeps'' R. M. Bailey, 1959 (sharphead darter) * ''Etheostoma akatulo'' Layman & Mayden, 2009 (bluemask darter) * '' Etheostoma artesiae'' ( O. P. Hay, 1881) (redspot darter) * '' Etheostoma asprigene'' ( S. A. Forbes, 1878) (mud darter) * '' Etheostoma atripinne'' ( D. S. Jordan, 1877) (Cumberland snubnose darter) * '' Etheostoma australe'' D. S. Jordan, 1889 (Conchos darter) * '' Etheostoma autumnale'' Mayden, 2010 (autumn darter) * '' E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urbanization
Urbanization (or urbanisation) refers to the population shift from rural to urban areas, the corresponding decrease in the proportion of people living in rural areas, and the ways in which societies adapt to this change. It is predominantly the process by which towns and cities are formed and become larger as more people begin living and working in central areas. Although the two concepts are sometimes used interchangeably, urbanization should be distinguished from urban growth. Urbanization refers to the ''proportion'' of the total national population living in areas classified as urban, whereas urban growth strictly refers to the ''absolute'' number of people living in those areas. It is predicted that by 2050 about 64% of the developing world and 86% of the developed world will be urbanized. That is equivalent to approximately 3 billion urbanites by 2050, much of which will occur in Africa and Asia. Notably, the United Nations has also recently projected that nearly all gl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Territory (animal)
In ethology, territory is the sociographical area that an animal consistently defends against conspecific competition (or, occasionally, against animals of other species) using agonistic behaviors or (less commonly) real physical aggression. Animals that actively defend territories in this way are referred to as being territorial or displaying territorialism. Territoriality is only shown by a minority of species. More commonly, an individual or a group of animals occupies an area that it habitually uses but does not necessarily defend; this is called its home range. The home ranges of different groups of animals often overlap, and in these overlap areas the groups tend to avoid each other rather than seeking to confront and expel each other. Within the home range there may be a ''core area'' that no other individual group uses, but, again, this is as a result of avoidance. Function The ultimate function of animals inhabiting and defending a territory is to increase the indi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Group Spawning
A group is a number of persons or things that are located, gathered, or classed together. Groups of people * Cultural group, a group whose members share the same cultural identity * Ethnic group, a group whose members share the same ethnic identity * Religious group (other), a group whose members share the same religious identity * Social group, a group whose members share the same social identity * Tribal group, a group whose members share the same tribal identity * Organization, an entity that has a collective goal and is linked to an external environment * Peer group, an entity of three or more people with similar age, ability, experience, and interest Social science * In-group and out-group * Primary, secondary, and reference groups * Social group * Collectives Science and technology Mathematics * Group (mathematics), a set together with a binary operation satisfying certain algebraic conditions Chemistry * Functional group, a group of atoms whic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substrate (marine Biology)
Stream substrate (sediment) is the material that rests at the bottom of a stream. There are several classification guides. One is: *Mud – silt and clay. *Sand – Particles between 0.06 and 2 mm in diameter. * Granule – Between 2 and 4 mm in diameter. *Pebble – Between 4 – 64 mm in diameter. *Cobble – between 6.4 and 25.6 cm in diameter *Boulder – more than 25.6 cm in diameter. Stream substrate can affect the life found within the stream habitat. Muddy streams generally have more sediment in the water, reducing clarity. Clarity is one guide to stream health. Marine substrate can be classified geologically as well. See Green et al., 1999 for a reference. Mollusks and clams that live in areas with substrate, and need them to survive, use their silky byssal threads to cling to it. See Cteniodes Ales for reference. See also * Grain size * Substrate (biology) In biology, a substrate is the surface on which an organism (such as a plant, fungus, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Noturus Flavus
''Noturus flavus'', the stonecat, is a North American freshwater catfish of the family Ictaluridae. The common name is due to its habit of hiding near or under stones in fast-moving water. Anatomy Stonecats are small, slender, flat-headed catfishes, with the adipose fin keel-like and continuous with the caudal fin except for a shallow notch. While the dorsal and pectoral spines of most members of this family cause wounds that irritate, the stonecat has venom glands, particularly on the bases of the pectoral spines, that cause extreme pain similar to that of a wasp sting. The pectoral fin lacks any posterior serrae. Anal fin rays number 15 to 18, pectoral fin rays 9 to 11, and pelvic fin rays 8 to 10. The caudal fin rays number 55 to 67. The upper jaw projects beyond the lower jaw and the tooth pad on the upper jaw has a narrow, crescent-shaped extension on each side. The premaxillary band of teeth has lateral backward extensions. The skin of the stonecat is thick and is yellow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lota Lota
The burbot (''Lota lota'') is the only gadiform (cod-like) freshwater fish. It is also known as bubbot, mariah, loche, cusk, freshwater cod, freshwater ling, freshwater cusk, the lawyer, coney-fish, lingcod, and eelpout. The species is closely related to the marine common ling and the cusk. It is the only member of the genus ''Lota''. For some time of the year, the burbot lives under ice, and it requires frigid temperatures to breed. Etymology The name burbot comes from the Latin word ''barba'', meaning beard, referring to its single chin whisker, or barbel. Its generic and specific names, ''Lota lota'', comes from the old French ''lotte'' fish, which is also named "barbot" in Old French. Description With an appearance like a cross between a catfish and an eel, the burbot has a serpent-like body, but is easily distinguished by a single barbel on the chin. The body is elongated and laterally compressed, with a flattened head and single, tube-like projection for each nostril. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trichoptera
The caddisflies, or order Trichoptera, are a group of insects with aquatic larvae and terrestrial adults. There are approximately 14,500 described species, most of which can be divided into the suborders Integripalpia and Annulipalpia on the basis of the adult mouthparts. Integripalpian larvae construct a portable casing to protect themselves as they move around looking for food, while Annulipalpian larvae make themselves a fixed retreat in which they remain, waiting for food to come to them. The affinities of the small third suborder Spicipalpia are unclear, and molecular analysis suggests it may not be monophyletic. Also called sedge-flies or rail-flies, the adults are small moth-like insects with two pairs of hairy membranous wings. They are closely related to the Lepidoptera (moths and butterflies) which have scales on their wings; the two orders together form the superorder Amphiesmenoptera. The aquatic larvae are found in a wide variety of habitats such as streams, river ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insectivore
A robber fly eating a hoverfly An insectivore is a carnivorous animal or plant that eats insects. An alternative term is entomophage, which can also refer to the human practice of eating insects. The first vertebrate insectivores were amphibians. When they evolved 400 million years ago, the first amphibians were piscivores, with numerous sharp conical teeth, much like a modern crocodile. The same tooth arrangement is however also suited for eating animals with exoskeletons, thus the ability to eat insects is an extension of piscivory. At one time, insectivorous mammals were scientifically classified in an order called Insectivora. This order is now abandoned, as not all insectivorous mammals are closely related. Most of the Insectivora taxa have been reclassified; those that have not yet been reclassified and found to be truly related to each other remain in the order Eulipotyphla. Although individually small, insects exist in enormous numbers. Insects make u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
