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Allen's Rule
Allen's rule is an ecogeographical rule formulated by Joel Asaph Allen in 1877, broadly stating that animals adapted to cold climates have shorter and thicker limbs and bodily Appendage, appendages than animals adapted to warm climates. More specifically, it states that the body surface-area-to-volume ratio for Homeothermy, homeothermic animals varies with the average temperature of the habitat to which they are adapted (i.e. the ratio is low in cold climates and high in hot climates). Explanation Allen's rule predicts that endotherm, endothermic animals with the same body volume should have different surface areas that will either aid or impede their heat dissipation. Because animals living in cold climates need to conserve as much heat as possible, Allen's rule predicts that they should have evolved comparatively low surface area-to-volume ratios to minimize the surface area by which they dissipate heat, allowing them to retain more heat. For animals living in warm climates, Al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allens Rule, Lepus, Hare, Ears, Earth
Allen, Allen's or Allens may refer to: Buildings * Allen Arena, an indoor arena at Lipscomb University in Nashville, Tennessee * Allen Center, a skyscraper complex in downtown Houston, Texas * Allen Fieldhouse, an indoor sports arena on the University of Kansas campus in Lawrence * Allen House (other) * Allen Power Plant (other) Businesses *Allen (brand), an American tool company *Allen's, an Australian brand of confectionery *Allens (law firm), an Australian law firm formerly known as Allens Arthur Robinson *Allen's (restaurant), a former hamburger joint and nightclub in Athens, Georgia, United States *Allen & Company LLC, a small, privately held investment bank *Allens of Mayfair, a butcher shop in London from 1830 to 2015 *Allens Boots, a retail store in Austin, Texas * Allens, Inc., a brand of canned vegetables based in Arkansas, US, now owned by Del Monte Foods *Allen's department store, a.k.a. Allen's, George Allen, Inc., Philadelphia, USA People * Allen (s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Common Frog
The common frog or grass frog (''Rana temporaria''), also known as the European common frog, European common brown frog, European grass frog, European Holarctic true frog, European pond frog or European brown frog or simply the frog, is a semi-aquatic amphibian of the family Ranidae, found throughout much of Europe as far north as Scandinavia and as far east as the Urals, except for most of the Iberian Peninsula, southern Italy, and the southern Balkans. The farthest west it can be found is Ireland. It is also found in Asia, and eastward to Japan. The nominative, and most common, subspecies ''Rana temporaria temporaria'' is a largely terrestrial frog native to Europe. It is distributed throughout northern Europe and can be found in Ireland, the Isle of Lewis and as far east as Japan. Common frogs metamorphose through three distinct developmental life stages — aquatic larva, terrestrial juvenile, and adult. They have corpulent bodies with a rounded snout, webbed feet an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nasal Passage
The nasal cavity is a large, air-filled space above and behind the nose in the middle of the face. The nasal septum divides the cavity into two cavities, also known as fossae. Each cavity is the continuation of one of the two nostrils. The nasal cavity is the uppermost part of the respiratory system and provides the nasal passage for inhaled air from the nostrils to the nasopharynx and rest of the respiratory tract. The paranasal sinuses surround and drain into the nasal cavity. Structure The term "nasal cavity" can refer to each of the two cavities of the nose, or to the two sides combined. The lateral wall of each nasal cavity mainly consists of the maxilla. However, there is a deficiency that is compensated for by the perpendicular plate of the palatine bone, the medial pterygoid plate, the labyrinth of ethmoid and the inferior concha. The paranasal sinuses are connected to the nasal cavity through small orifices called ostia. Most of these ostia communicate with the nos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mean Annual Temperature And Brachial Index In Selected Modern Populations
A mean is a quantity representing the "center" of a collection of numbers and is intermediate to the extreme values of the set of numbers. There are several kinds of means (or "measures of central tendency") in mathematics, especially in statistics. Each attempts to summarize or typify a given group of data, illustrating the magnitude and sign of the data set. Which of these measures is most illuminating depends on what is being measured, and on context and purpose. The ''arithmetic mean'', also known as "arithmetic average", is the sum of the values divided by the number of values. The arithmetic mean of a set of numbers ''x''1, ''x''2, ..., x''n'' is typically denoted using an overhead bar, \bar. If the numbers are from observing a sample of a larger group, the arithmetic mean is termed the ''sample mean'' (\bar) to distinguish it from the group mean (or expected value) of the underlying distribution, denoted \mu or \mu_x. Outside probability and statistics, a wide range of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indigenous Peoples
There is no generally accepted definition of Indigenous peoples, although in the 21st century the focus has been on self-identification, cultural difference from other groups in a state, a special relationship with their traditional territory, and an experience of subjugation and discrimination under a dominant cultural model. Estimates of the population of Indigenous peoples range from 250 million to 600 million. There are some 5,000 distinct Indigenous peoples spread across every inhabited climate zone and inhabited continent of the world. Most Indigenous peoples are in a minority in the state or traditional territory they inhabit and have experienced domination by other groups, especially non-Indigenous peoples. Although many Indigenous peoples have experienced colonization by settlers from European nations, Indigenous identity is not determined by Western colonization. The rights of Indigenous peoples are outlined in national legislation, treaties and international law ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Body Mass Index
Body mass index (BMI) is a value derived from the mass (Mass versus weight, weight) and height of a person. The BMI is defined as the human body weight, body mass divided by the square (algebra), square of the human height, body height, and is expressed in Units of measurement, units of kg/m2, resulting from mass in kilograms (kg) and height in metres (m). The BMI may be determined first by measuring its components by means of a weighing scale and a stadiometer. The multiplication and division may be carried out directly, by hand or using a calculator, or indirectly using a lookup table (or chart). The table displays BMI as a function of mass and height and may show other units of measurement (converted to Metric system, metric units for the calculation). The table may also show contour lines or colours for different BMI categories. The BMI is a convenient rule of thumb used to broadly categorize a person as based on tissue mass (muscle, fat, and bone) and height. Major adult B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peru
Peru, officially the Republic of Peru, is a country in western South America. It is bordered in the north by Ecuador and Colombia, in the east by Brazil, in the southeast by Bolivia, in the south by Chile, and in the south and west by the Pacific Ocean. Peru is a Megadiverse countries, megadiverse country, with habitats ranging from the arid plains of the Pacific coastal region in the west, to the peaks of the Andes mountains extending from the north to the southeast of the country, to the tropical Amazon basin rainforest in the east with the Amazon River. Peru has Demographics of Peru, a population of over 32 million, and its capital and largest city is Lima. At , Peru is the List of countries and dependencies by area, 19th largest country in the world, and the List of South American countries by area, third largest in South America. Pre-Columbian Peru, Peruvian territory was home to Andean civilizations, several cultures during the ancient and medieval periods, and has one o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eskimo Group - NARA - 523819
''Eskimo'' () is a controversial exonym that refers to two closely related Indigenous peoples: Inuit (including the Alaska Native Iñupiat, the Canadian Inuit, and the Greenlandic Inuit) and the Yupik peoples, Yupik (or Siberian Yupik, Yuit) of eastern Siberia and Alaska. A related third group, Aleuts, who inhabit the Aleutian Islands, are generally excluded from the definition of ''Eskimo''. The three groups share a relatively recent common ancestor, and speak related languages belonging to the family of Eskaleut languages. These circumpolar peoples have traditionally inhabited the Arctic and subarctic regions from eastern Siberia (Russia) to Alaska (United States), Northern Canada, Nunavik, Nunatsiavut, and Greenland. Some Inuit, Yupik, Aleut, and other individuals consider the term ''Eskimo'', which is of a disputed etymology, to be pejorative or even offensive. ''Eskimo'' continues to be used within a historical, linguistic, archaeological, and cultural context. The governm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microevolution
Microevolution is the change in allele frequencies that occurs over time within a population. This change is due to four different processes: mutation, selection ( natural and artificial), gene flow and genetic drift. This change happens over a relatively short (in evolutionary terms) amount of time compared to the changes termed macroevolution. Population genetics is the branch of biology that provides the mathematical structure for the study of the process of microevolution. Ecological genetics concerns itself with observing microevolution in the wild. Typically, observable instances of evolution are examples of microevolution; for example, bacterial strains that have antibiotic resistance. Microevolution provides the raw material for macroevolution. Difference from macroevolution Macroevolution is guided by sorting of interspecific variation ("species selection"), as opposed to sorting of intraspecific variation in microevolution. Species selection may occur as (a) eff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ectotherm
An ectotherm (), more commonly referred to as a "cold-blooded animal", is an animal in which internal physiological sources of heat, such as blood, are of relatively small or of quite negligible importance in controlling body temperature.Davenport, John. Animal Life at Low Temperature. Publisher: Springer 1991. Such organisms (frogs, for example) rely on environmental heat sources, which permit them to operate at very economical metabolic rates. Some of these animals live in environments where temperatures are practically constant, as is typical of regions of the abyssal ocean and hence can be regarded as homeothermic ectotherms. In contrast, in places where temperature varies so widely as to limit the physiological activities of other kinds of ectotherms, many species habitually seek out external sources of heat or shelter from heat; for example, many reptiles regulate their body temperature by basking in the sun, or seeking shade when necessary in addition to a host of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prediction
A prediction (Latin ''præ-'', "before," and ''dictum'', "something said") or forecast is a statement about a future event or about future data. Predictions are often, but not always, based upon experience or knowledge of forecasters. There is no universal agreement about the exact difference between "prediction" and " estimation"; different authors and disciplines ascribe different connotations. Future events are necessarily uncertain, so guaranteed accurate information about the future is impossible. Prediction can be useful to assist in making plans about possible developments. Opinion In a non-statistical sense, the term "prediction" is often used to refer to an informed guess or opinion. A prediction of this kind might be informed by a predicting person's abductive reasoning, inductive reasoning, deductive reasoning, and experience; and may be useful—if the predicting person is a knowledgeable person in the field. The Delphi method is a technique for elicitin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bergmann's Rule
Bergmann's rule is an ecogeographical rule that states that, within a broadly distributed taxonomic clade, populations and species of larger size are found in colder environments, while populations and species of smaller size are found in warmer regions. The rule derives from the relationship between size in linear dimensions meaning that both height and volume will increase in colder environments. Bergmann's rule only describes the overall size of the animals, but does not include body proportions like Allen's rule does. Although originally formulated in relation to species within a genus, it has often been recast in relation to populations within a species. It is also often cast in relation to latitude. It is possible that the rule also applies to some plants, such as '' Rapicactus''. The rule is named after nineteenth century German biologist Carl Bergmann, who described the pattern in 1847, although he was not the first to notice it. Bergmann's rule is most often applied t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
