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Semelparity
Semelparity and iteroparity are two contrasting reproductive strategies available to living organisms. A species is considered semelparous if it is characterized by a single reproductive episode before death, and iteroparous if it is characterized by multiple reproductive cycles over the course of its lifetime. Iteroparity can be further divided into continuous iteroparity (primates including humans and chimpanzees) and seasonal iteroparity (birds, dogs, etc.) Some botanists use the parallel terms monocarpy and polycarpy. (See also plietesials.) In truly semelparous species, death after reproduction is part of an overall strategy that includes putting all available resources into maximizing reproduction, at the expense of future life (see § Trade-offs). In any iteroparous population there will be some individuals who die between their first and second reproductive episodes, but unless this is part of a syndrome of programmed death after reproduction, this would not be called ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plietesials
Plietesials are plants that grow for a number of years, flower gregariously (synchronously), set seed and then die. The length of the cycle can vary between 8 and 16 years. For example, the neelakurinji plant flowers every 12 years and bloomed as expected in 2006 and 2018 in the Munnar region of Kerala, India. Certain species of unrelated families of flowering plants (including Poaceae, Arecaceae, Scrophulariaceae, Fabaceae, Apocynaceae, and Acanthaceae) are plietesial. The term plietesial has been used in reference to perennial monocarpic plants "of the kind most often met with in the Strobilanthinae" (a subtribe of Acanthaceae containing Strobilanthes and allied genera) that usually grow gregariously, flower simultaneously following a long interval, set seed, and die. Other commonly used expressions or terms describing a plietesial life history include gregarious flowering, mast seeding, and supra-annual synchronized semelparity (semelparity = monocarpy).Daniel, Thomas F. 2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lobelia Telekii
''Lobelia telekii'' is a species of flowering plant in the family Campanulaceae, that is found only in the alpine zones of Mount Kenya, Mount Elgon, and the Aberdare Mountains of East Africa. It occurs at higher altitudes on well-drained sloped hillsides. It is a semelparous species, putting all its reproductive effort into producing single large inflorescence up to tall, and then dying. Inflorescences of ''L. telekii'' also possesses a large pith-volume for internal water storage and marcescent foliage which could provide insulation. It secretes a polysaccharide into this reservoir, which may be useful for its survival in the cold climate. The plant is named after the Austro-Hungarian explorer, Count Sámuel Teleki. ''L. telekii'' plants usually consist of a single rosette, which grows for several decades, flowers once, and then dies. However, a very small number of plants have multiple rosettes connected by an underground stem. Each flower is subtended by a long hairy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fecundity
Fecundity is defined in two ways; in human demography, it is the potential for reproduction of a recorded population as opposed to a sole organism, while in population biology, it is considered similar to fertility, the natural capability to produce offspring, measured by the number of gametes (eggs), seed set, or asexual propagules. Superfecundity refers to an organism's ability to store another organism's sperm (after copulation) and fertilize its own eggs from that store after a period of time, essentially making it appear as though fertilization occurred without sperm (i.e. parthenogenesis). Human demography Human demography considers only human fecundity, at its culturally differing rates, while population biology studies all organisms. The term ''fecundity'' in population biology is often used to describe the rate of offspring production after one time step (often annual). In this sense, fecundity may include both birth rates and survival of young to that time step. Whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agave
''Agave'' (; ; ) is a genus of monocots native to the hot and arid regions of the Americas and the Caribbean, although some ''Agave'' species are also native to tropical areas of North America, such as Mexico. The genus is primarily known for its succulent and xerophytic species that typically form large rosettes of strong, fleshy leaves. ''Agave'' now includes species formerly placed in a number of other genera, such as ''Manfreda'', ×''Mangave'', ''Polianthes'' and ''Prochnyanthes''. Many plants in this genus may be considered perennial, because they require several to many years to mature and flower. However, most ''Agave'' species are more accurately described as monocarpic rosettes or multiannuals, since each individual rosette flowers only once and then dies; a small number of ''Agave'' species are polycarpic. Maguey flowers are considered edible in many indigenous culinary traditions of Mesoamerica. Along with plants from the closely related genera ''Yucca'', ''Hes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Capelin
The capelin or caplin (''Mallotus villosus'') is a small forage fish of the smelt family found in the North Atlantic, North Pacific and Arctic oceans. In summer, it grazes on dense swarms of plankton at the edge of the ice shelf. Larger capelin also eat a great deal of krill and other crustaceans. Among others, whales, seals, Atlantic cod, Atlantic mackerel, squid and seabirds prey on capelin, in particular during the spawning season while the capelin migrate south. Capelin spawn on sand and gravel bottoms or sandy beaches at the age of two to six years. When spawning on beaches, capelin have an extremely high post-spawning mortality rate which, for males, is close to 100%. Males reach in length, while females are up to long. They are olive-coloured dorsally, shading to silver on sides. Males have a translucent ridge on both sides of their bodies. The ventral aspects of the males iridesce reddish at the time of spawn. Capelin migration Capelin populations in the Barents S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Madagascar
Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa across the Mozambique Channel. At Madagascar is the world's second-largest island country, after Indonesia. The nation is home to around 30 million inhabitants and consists of the island of Madagascar (the fourth-largest island in the world), along with numerous smaller peripheral islands. Following the prehistoric breakup of the supercontinent Gondwana, Madagascar split from the Indian subcontinent around 90 million years ago, allowing native plants and animals to evolve in relative isolation. Consequently, Madagascar is a biodiversity hotspot; over 90% of its wildlife is endemic. Human settlement of Madagascar occurred during or before the mid first millennium AD by Austronesian peoples, presumably arriving on outrigger cano ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sow With Piglet
Sow or SOW may refer to: * Sowing, the process of planting Female animals * Badger * Bear * Guinea pig * Hedgehog * Suidae ** Wild boar ** Pig Arts, entertainment and media * Sow (band), a musical project of Anna Wildsmith * "Sow", a poem by Sylvia Plath * Sow (playing card), common name for the Deuce in cards games in southern Germany Places * Show Low Regional Airport (IATA airport code), Arizona, US * Sowerby Bridge railway station (Network Rail station code), England * River Sow, England People * Aminata Sow Fall (born 1941), Senegalese author * Abdoul Salam Sow (born 1970), Guinean footballer * Abdoulaye Sékou Sow (1931–2013), former Prime Minister of Mali * Abdourahmane Sow (born 1942), Minister of the Interior of Senegal, chair of the World Scout Committee * Baba Sow (born 1995), Senegalese footballer * Daouda Sow (politician) (1933–2009), Senegalese politician * Daouda Sow (boxer) (born 1983), boxer * Fatou Ndiaye Sow (1937–2004), Senegalese poet * Ismaël S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastrointestinal Bleeding
Gastrointestinal bleeding (GI bleed), also called gastrointestinal hemorrhage (GIB), is all forms of bleeding in the gastrointestinal tract, from the mouth to the rectum. When there is significant blood loss over a short time, symptoms may include vomiting red blood, vomiting black blood, bloody stool, or black stool. Small amounts of bleeding over a long time may cause iron-deficiency anemia resulting in feeling tired or heart-related chest pain. Other symptoms may include abdominal pain, shortness of breath, pale skin, or passing out. Sometimes in those with small amounts of bleeding no symptoms may be present. Bleeding is typically divided into two main types: upper gastrointestinal bleeding and lower gastrointestinal bleeding. Causes of upper GI bleeds include: peptic ulcer disease, esophageal varices due to liver cirrhosis and cancer, among others. Causes of lower GI bleeds include: hemorrhoids, cancer, and inflammatory bowel disease among others. Diagnosis typicall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corticosteroid
Corticosteroids are a class of steroid hormones that are produced in the adrenal cortex of vertebrates, as well as the synthetic analogues of these hormones. Two main classes of corticosteroids, glucocorticoids and mineralocorticoids, are involved in a wide range of physiological processes, including stress response, immune response, and regulation of inflammation, carbohydrate metabolism, protein catabolism, blood electrolyte levels, and behavior. Some common naturally occurring steroid hormones are cortisol (), corticosterone (), cortisone () and aldosterone (). (Note that cortisone and aldosterone are isomers.) The main corticosteroids produced by the adrenal cortex are cortisol and aldosterone. Classes * Glucocorticoids such as cortisol affect carbohydrate, fat, and protein metabolism, and have anti-inflammatory, immunosuppressive, anti-proliferative, and vasoconstrictive effects. Anti-inflammatory effects are mediated by blocking the action of inflamm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
R/K Selection Theory
In ecology, ''r''/''K'' selection theory relates to the selection of combinations of traits in an organism that trade off between quantity and quality of offspring. The focus on either an increased quantity of offspring at the expense of individual parental investment of ''r''-strategists, or on a reduced quantity of offspring with a corresponding increased parental investment of ''K''-strategists, varies widely, seemingly to promote success in particular environments. The concepts of quantity or quality offspring are sometimes referred to as "cheap" or "expensive", a comment on the expendable nature of the offspring and parental commitment made. The stability of the environment can predict if many expendable offspring are made or if fewer offspring of higher quality would lead to higher reproductive success. An unstable environment would encourage the parent to make many offspring, because the likelihood of all (or the majority) of them surviving to adulthood is slim. In contras ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bamboo
Bamboos are a diverse group of evergreen perennial flowering plants making up the subfamily Bambusoideae of the grass family Poaceae. Giant bamboos are the largest members of the grass family. The origin of the word "bamboo" is uncertain, but it probably comes from the Dutch or Portuguese language, which originally borrowed it from Malay or Kannada. In bamboo, as in other grasses, the internodal regions of the stem are usually hollow and the vascular bundles in the cross-section are scattered throughout the stem instead of in a cylindrical arrangement. The dicotyledonous woody xylem is also absent. The absence of secondary growth wood causes the stems of monocots, including the palms and large bamboos, to be columnar rather than tapering. Bamboos include some of the fastest-growing plants in the world, due to a unique rhizome-dependent system. Certain species of bamboo can grow within a 24-hour period, at a rate of almost an hour (equivalent to 1 mm every 90 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of Mammalogy
The ''Journal of Mammalogy'' is a bimonthly peer-reviewed scientific journal published by Oxford University Press on behalf of the American Society of Mammalogists. Both the society and the journal were established in 1919. The journal covers research on mammals throughout the world, including their ecology, genetics, conservation, behavior, systematics, morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines * Morphology (archaeology), study of the shapes or forms of artifacts * Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies ..., and physiology. The journal also publishes news about the society and advertises student scholarship opportunities. See also * Barbara Hibbs Blake * '' Mammalian Species'' References External links * * Academic journals associated with learned and professional societies Bimonthly journals English-language journals Mammalogy journals Publications est ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
