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Hibernation
Hibernation is a state of minimal activity and metabolic depression undergone by some animal species. Hibernation is a seasonal heterothermy characterized by low body-temperature, slow breathing and heart-rate, and low metabolic rate. It most commonly occurs during winter months. Although traditionally reserved for "deep" hibernators such as rodents, the term has been redefined to include animals such as bears and is now applied based on active metabolic suppression rather than any absolute decline in body temperature. Many experts believe that the processes of daily torpor and hibernation form a continuum and utilise similar mechanisms. The equivalent during the summer months is aestivation. Hibernation functions to conserve energy when sufficient food is not available. To achieve this energy saving, an endothermic animal decreases its metabolic rate and thereby its body temperature. Hibernation may last days, weeks, or months—depending on the species, ambient temperatu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Black Bear
The American black bear (''Ursus americanus''), also called simply a black bear or sometimes a baribal, is a medium-sized bear endemic to North America. It is the continent's smallest and most widely distributed bear species. American black bears are omnivores, with their diets varying greatly depending on season and location. They typically live in largely forested areas, but will leave forests in search of food, and are sometimes attracted to human communities due to the immediate availability of food. The International Union for Conservation of Nature (IUCN) lists the American black bear as a least-concern species, due to its widespread distribution and a large population estimated to be twice that of all other bear species combined. Along with the brown bear (''Ursus arctos''), it is one of only two modern bear species not considered by the IUCN to be globally threatened with extinction. Taxonomy and evolution Despite living in North America, American black bears are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bear
Bears are carnivoran mammals of the family Ursidae. They are classified as caniforms, or doglike carnivorans. Although only eight species of bears are extant, they are widespread, appearing in a wide variety of habitats throughout the Northern Hemisphere and partially in the Southern Hemisphere. Bears are found on the continents of North America, South America, Europe, and Asia. Common characteristics of modern bears include large bodies with stocky legs, long snouts, small rounded ears, shaggy hair, plantigrade paws with five nonretractile claws, and short tails. While the polar bear is mostly carnivorous, and the giant panda feeds almost entirely on bamboo, the remaining six species are omnivorous with varied diets. With the exception of courting individuals and mothers with their young, bears are typically solitary animals. They may be diurnal or nocturnal and have an excellent sense of smell. Despite their heavy build and awkward gait, they are adept runners, c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterothermy
Heterothermy or heterothermia (from Greek ἕτερος ''heteros'' "other" and θέρμη ''thermē'' "heat") is a physiological term for animals that vary between self-regulating their body temperature, and allowing the surrounding environment to affect it. In other words, they exhibit characteristics of both poikilothermy and homeothermy. Definition Heterothermic animals are those that can switch between poikilothermic and homeothermic strategies. These changes in strategies typically occur on a daily basis or on an annual basis. More often than not, it is used as a way to dissociate the fluctuating metabolic rates seen in some small mammals and birds (e.g. bats and hummingbirds), from those of traditional cold blooded animals. In many bat species, body temperature and metabolic rate are elevated only during activity. When at rest, these animals reduce their metabolisms drastically, which results in their body temperature dropping to that of the surrounding environment. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brumation
Dormancy is a period in an organism's life cycle when growth, development, and (in animals) physical activity are temporarily stopped. This minimizes metabolic activity and therefore helps an organism to conserve energy. Dormancy tends to be closely associated with environmental conditions. Organisms can synchronize entry to a dormant phase with their environment through predictive or consequential means. Predictive dormancy occurs when an organism enters a dormant phase ''before'' the onset of adverse conditions. For example, photoperiod and decreasing temperature are used by many plants to predict the onset of winter. Consequential dormancy occurs when organisms enter a dormant phase ''after'' adverse conditions have arisen. This is commonly found in areas with an unpredictable climate. While very sudden changes in conditions may lead to a high mortality rate among animals relying on consequential dormancy, its use can be advantageous, as organisms remain active longer and are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dormancy
Dormancy is a period in an organism's life cycle when growth, development, and (in animals) physical activity are temporarily stopped. This minimizes metabolic activity and therefore helps an organism to conserve energy. Dormancy tends to be closely associated with environmental conditions. Organisms can synchronize entry to a dormant phase with their environment through predictive or consequential means. Predictive dormancy occurs when an organism enters a dormant phase ''before'' the onset of adverse conditions. For example, photoperiod and decreasing temperature are used by many plants to predict the onset of winter. Consequential dormancy occurs when organisms enter a dormant phase ''after'' adverse conditions have arisen. This is commonly found in areas with an unpredictable climate. While very sudden changes in conditions may lead to a high mortality rate among animals relying on consequential dormancy, its use can be advantageous, as organisms remain active longer and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bat In Mine JAPAN
Bats are mammals of the order Chiroptera.''cheir'', "hand" and πτερόν''pteron'', "wing". With their forelimbs adapted as wings, they are the only mammals capable of true and sustained flight. Bats are more agile in flight than most birds, flying with their very long spread-out digits covered with a thin membrane or patagium. The smallest bat, and arguably the smallest extant mammal, is Kitti's hog-nosed bat, which is in length, across the wings and in mass. The largest bats are the flying foxes, with the giant golden-crowned flying fox, ''Acerodon jubatus'', reaching a weight of and having a wingspan of . The second largest order of mammals after rodents, bats comprise about 20% of all classified mammal species worldwide, with over 1,400 species. These were traditionally divided into two suborders: the largely fruit-eating megabats, and the echolocating microbats. But more recent evidence has supported dividing the order into Yinpterochiroptera and Yangochiropter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arctic Ground Squirrel
The Arctic ground squirrel (''Urocitellus parryii'') (Inuktitut: ''ᓯᒃᓯᒃ, siksik'') is a species of ground squirrel native to the Arctic and Subarctic of North America and Asia. People in Alaska, particularly around the Aleutians, refer to them as "parka" squirrels, most likely because their pelt is good for the ruff on parkas and for clothing. Taxonomy Subspecies listed alphabetically. *''U. p. ablusus'' Osgood, 1903 *''U. p. kennicottii'' Ross, 1861 – Barrow ground squirrel (northern Alaska, northern Yukon, and northern Northwest Territories) *''U. p. kodiacensis'' Ross, 1861 *''U. p. leucostictus'' Brandt, 1844 *''U. p. lyratus'' Hall and Gilmore, 1932 *''U. p. nebulicola'' Osgood, 1903 *''U. p. osgoodi'' Merriam, 1900 *''U. p. parryii'' Richardson, 1825 *''U. p. plesius'' Osgood, 1900 *''U. p. stejnegeri'' J. A. Allen, 1903 Description The Arctic ground squirrel has a beige and tan coat with a white-spotted back. This squirrel has a short face, small ears, a dark tai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torpor
Torpor is a state of decreased physiological activity in an animal, usually marked by a reduced body temperature and metabolic rate. Torpor enables animals to survive periods of reduced food availability. The term "torpor" can refer to the time a hibernator spends at low body temperature, lasting days to weeks, or it can refer to a period of low body temperature and metabolism lasting less than 24 hours, as in "daily torpor". Animals that undergo daily torpor include birds (even tiny hummingbirds, notably Cypselomorphae) and some mammals, including many marsupial species, rodent species (such as mice), and bats. During the active part of their day, such animals maintain normal body temperature and activity levels, but their metabolic rate and body temperature drop during a portion of the day (usually night) to conserve energy. Some animals seasonally go into long periods of inactivity, with reduced body temperature and metabolism, made up of multiple bouts of torpor. This ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aestivation
Aestivation ( la, aestas (summer); also spelled estivation in American English) is a state of animal dormancy, similar to hibernation, although taking place in the summer rather than the winter. Aestivation is characterized by inactivity and a lowered metabolic rate, that is entered in response to high temperatures and arid conditions. It takes place during times of heat and dryness, the hot dry season, which are often the summer months. Invertebrate and vertebrate animals are known to enter this state to avoid damage from high temperatures and the risk of desiccation. Both terrestrial and aquatic animals undergo aestivation. Fossil records suggest that aestivation may have evolved several hundred million years ago. Physiology Organisms that aestivate appear to be in a fairly "light" state of dormancy, as their physiological state can be rapidly reversed, and the organism can quickly return to a normal state. A study done on '' Otala lactea'', a snail native to parts of Euro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black-tailed Prairie Dog
The black-tailed prairie dog (''Cynomys ludovicianus'') is a rodent of the family Sciuridae found in the Great Plains of North America from about the United States-Canada border to the United States-Mexico border. Unlike some other prairie dogs, these animals do not truly hibernate. The black-tailed prairie dog can be seen above ground in midwinter. A black-tailed prairie dog town in Texas was reported to cover and included 400,000,000 individuals. Prior to habitat destruction, the species may have been the most abundant prairie dog in central North America. It was one of two prairie dogs described by the Lewis and Clark Expedition in the journals and diaries of their expedition. Description Black-tailed prairie dogs are generally tan in color, with lighter-colored bellies. They may have color variation in their pelt, such as dark fur on their back in black and brown tones. Their tails have black tips, from which their name is derived. Adults can weigh from , males are typicall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
European Hedgehog
The European hedgehog (''Erinaceus europaeus''), also known as the West European hedgehog or common hedgehog, is a hedgehog species native to Europe from Iberia and Italy northwards into Scandinavia and westwards into the British Isles.Harris, S. & Yalden, D.W. (2008). ''Mammals of the British Isles: Handbook, 4th Edition.'' The Mammal Society, Southampton. It is a generally common and widely distributed species that can survive across a wide range of habitat types. It is a well-known species, and a favourite in European gardens, both for its endearing appearance and its preference for eating a range of garden pests. While populations are currently stable across much of its range, it is declining severely in Great Britain where it is now Red Listed (classified as near to extinction). Outside its native range, the species was introduced to New Zealand during the late-19th and early-20th centuries. Description The European hedgehog has a generalised body structure with unspeciali ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polistes Exclamans
''Polistes exclamans'', the Guinea paper wasp, is a social wasp and is part of the family Vespidae of the order Hymenoptera. It is found throughout the United States, Mexico, the Bahamas, Jamaica and parts of Canada. Due to solitary nest founding by queens, ''P. exclamans'' has extended its range in the past few decades and now covers the eastern half of the United States, as well as part of the north. This expansion is typically attributed to changing global climate and temperatures. ''P. exclamans'' has three specific castes, including males, workers, and queens, but the dominance hierarchy is further distinguished by age. The older the wasp is, the higher it is in ranking within the colony. In most ''P. exclamans'' nests, there is one queen who lays all the eggs in the colony. The physiological similarities between the worker and queen castes have led to experiments attempting to distinguish the characteristics of these two castes and how they are determined, though males have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
