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Jackson Ratio
Researched and devised by Dr. Oliphant Jackson, the Jackson ratio is a method of determining whether a member of the tortoise species ''Testudo graeca'' or ''Testudo hermanni'' is maintaining its optimum bodyweight, which is necessary for a successful hibernation. Calculation The Jackson ratio is calculated by taking the weight of the tortoise in grams and dividing it by the cube of the length of the tortoise's carapace A carapace is a dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tortoises, the und ... in centimeters. This is essentially a value of the density of the tortoise in g/cm3. The optimal value for this ratio is 0.21 with a range of 0.18–0.22 being acceptable for hibernation. Values significantly less than this indicate an underweight tortoise and larger values are indicative of overweight tortoises. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tortoise
Tortoises () are reptiles of the family Testudinidae of the order Testudines (Latin: ''tortoise''). Like other turtles, tortoises have a shell to protect from predation and other threats. The shell in tortoises is generally hard, and like other members of the suborder Cryptodira, they retract their necks and heads directly backward into the shell to protect them. Tortoises can vary in size with some species, such as the Galápagos giant tortoise, growing to more than in length, whereas others like the Speckled cape tortoise have shells that measure only long. Several lineages of tortoises have independently evolved very large body sizes in excess of 100 kg, including the Galapagos giant tortoise and the Aldabra giant tortoise. They are usually diurnal animals with tendencies to be crepuscular depending on the ambient temperatures. They are generally reclusive animals. Tortoises are the longest-living land animals in the world, although the longest-living specie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Testudo Graeca
The Greek tortoise (''Testudo graeca''), also known commonly as the spur-thighed tortoise, is a species of tortoise in the family Testudinidae. ''Testudo graeca'' is one of five species of Mediterranean tortoises (genera '' Testudo'' and '' Agrionemys''). The other four species are Hermann's tortoise (''T. hermanni''), the Egyptian tortoise (''T. kleinmanni''), the marginated tortoise (''T. marginata''), and the Russian tortoise (''A. horsfieldii''). The Greek tortoise is a very long-lived animal, achieving a lifespan upwards of 125 years, with some unverified reports up to 200 years. Geographic range The Greek tortoise's geographic range includes North Africa, Southern Europe, and Southwest Asia. It is prevalent in the Black Sea coast of the Caucasus (from Anapa, Russia, to Sukhumi, Abkhazia, Georgia (country), Georgia, to the south), as well as in other regions of Georgia (country), Georgia, Armenia, Iran, and Azerbaijan. Evolution The oldest known definitive fossil is fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Testudo Hermanni
Hermann's tortoise (''Testudo hermanni'') is a species of tortoise. Two subspecies are known: the western Hermann's tortoise (''T. h. hermanni'' ) and the eastern Hermann's tortoise (''T. h. boettgeri'' ). Sometimes mentioned as a subspecies, ''T. h. peleponnesica'' is not yet confirmed to be genetically different from ''T. h. boettgeri''. Etymology The specific epithet, ''hermanni'', honors French naturalist Johann Hermann.Beolens, Bo; Watkins, Michael; Grayson, Michael (2011). ''The Eponym Dictionary of Reptiles''. Baltimore: Johns Hopkins University Press. xiii + 296 pp. . (''Testudo hermanni'', p. 121; ''T. h. boettgeri'', p. 29). The subspecific name, ''boettgeri'', honors German herpetologist Oskar Boettger. Geographic range ''Testudo hermanni'' can be found throughout southern Europe. The western population (''T. h. hermanni'') is found in eastern Spain, southern France, the Balearic islands, Corsica, Sardinia, Sicily, southern and central Italy (Tuscany). The ea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Carapace
A carapace is a dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tortoises, the underside is called the plastron. Crustaceans In crustaceans, the carapace functions as a protective cover over the cephalothorax (i.e., the fused head and thorax, as distinct from the abdomen behind). Where it projects forward beyond the eyes, this projection is called a rostrum. The carapace is calcified to varying degrees in different crustaceans. Zooplankton within the phylum Crustacea also have a carapace. These include Cladocera, ostracods, and isopods, but isopods only have a developed "cephalic shield" carapace covering the head. Arachnids In arachnids, the carapace is formed by the fusion of prosomal tergites into a single plate which carries the eyes, ocularium, ozopores (a pair of openings of the scent gland of Opilione ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tortoises
Tortoises () are reptiles of the family Testudinidae of the order Testudines (Latin: ''tortoise''). Like other turtles, tortoises have a shell to protect from predation and other threats. The shell in tortoises is generally hard, and like other members of the suborder Cryptodira, they retract their necks and heads directly backward into the shell to protect them. Tortoises can vary in size with some species, such as the Galápagos giant tortoise, growing to more than in length, whereas others like the Speckled cape tortoise have shells that measure only long. Several lineages of tortoises have independently evolved very large body sizes in excess of 100 kg, including the Galapagos giant tortoise and the Aldabra giant tortoise. They are usually diurnal animals with tendencies to be crepuscular depending on the ambient temperatures. They are generally reclusive animals. Tortoises are the longest-living land animals in the world, although the longest-living species of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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