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Plethodon Cinereus
The red-backed salamander (''Plethodon cinereus'') is a small, hardy woodland salamander species in the family Plethodontidae. It is also known as the redback salamander, eastern red-backed salamander,Integrated Taxonomic Information System nternet2012. pdated 2012 Sept; cited 2012 Nov 26Available from: www.itis.gov or the northern red-backed salamander to distinguish it from the southern red-backed salamander (''Plethodon serratus''). The species inhabits wooded slopes in eastern North America, west to Missouri, south to North Carolina, and north from southern Quebec and the Maritime provinces in Canada to Minnesota. It is one of 56 species in the genus ''Plethodon''. Red-backed salamanders are notable for their color polymorphism and primarily display two color morph varieties ("red-backed" and "lead-backed"), which differ in physiology and anti-predator behavior. Description and ecology The red-backed salamander is a small terrestrial salamander, in total length (includin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plethodon
''Plethodon'' is a genus of salamanders in the family Plethodontidae. They are also known as woodland salamanders or, more rarely, slimy salamanders. All members of the genus are endemic to North America (Canada and USA). They have no aquatic larval stage. In some species, such as ''Plethodon cinereus'', the red-backed salamander, eggs are laid underneath a stone or log. Young hatch in the adult form. Members of ''Plethodon'' primarily eat small invertebrates. The earliest known fossils of this genus are from the Hemphillian of Tennessee in the United States. Species There are 56 species in the genus ''Plethodon''. Listed in alphabetical order of specific name: ''Nota bene'': A binomial authority In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ... in parentheses indicates that th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Woodland Salamander
''Plethodon'' is a genus of salamanders in the family Plethodontidae. They are also known as woodland salamanders or, more rarely, slimy salamanders. All members of the genus are endemic to North America (Canada and USA). They have no aquatic larval stage. In some species, such as ''Plethodon cinereus'', the red-backed salamander, eggs are laid underneath a stone or log. Young hatch in the adult form. Members of ''Plethodon'' primarily eat small invertebrates. The earliest known fossils of this genus are from the Hemphillian of Tennessee in the United States. Species There are 56 species in the genus ''Plethodon''. Listed in alphabetical order of specific name: ''Nota bene'': A binomial authority In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ... in parentheses indicates that th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gas Exchange
Gas exchange is the physical process by which gases move passively by Diffusion#Diffusion vs. bulk flow, diffusion across a surface. For example, this surface might be the air/water interface of a water body, the surface of a gas bubble in a liquid, a gas-permeable membrane, or a biological membrane that forms the boundary between an organism and its extracellular environment. Gases are constantly consumed and produced by Metabolism, cellular and metabolic reactions in most living things, so an efficient system for gas exchange between, ultimately, the interior of the cell(s) and the external environment is required. Small, particularly unicellular organisms, such as bacterium, bacteria and protozoa, have a high Surface-area-to-volume ratio, surface-area to volume ratio. In these creatures the gas exchange membrane is typically the cell membrane. Some small multicellular organisms, such as flatworms, are also able to perform sufficient gas exchange across the skin or cuticle that s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melanism
The term melanism refers to black pigment and is derived from the gr, μελανός. Melanism is the increased development of the dark-colored pigment melanin in the skin or hair. Pseudomelanism, also called abundism, is another variant of pigmentation, identifiable by dark spots or enlarged stripes, which cover a large part of the body of the animal, making it appear melanistic. The morbid deposition of black matter, often of a malignant character causing pigmented tumors, is called melanosis. Adaptation Melanism related to the process of adaptation is called adaptive. Most commonly, dark individuals become Fitness (biology), fitter to survive and reproduce in their environment as they are better camouflaged. This makes some species less conspicuous to predators, while others, such as leopards, use it as a foraging advantage during night hunting. Typically, adaptive melanism is Heritability, heritable: A Dominance (genetics), dominant allele, which is entirely or nearly ent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amelanism
Amelanism (also known as amelanosis) is a pigmentation abnormality characterized by the lack of pigments called melanins, commonly associated with a genetic loss of tyrosinase function. Amelanism can affect fish, amphibians, reptiles, birds, and mammals including humans. The appearance of an amelanistic animal depends on the remaining non-melanin pigments. The opposite of amelanism is melanism, a higher percentage of melanin. A similar condition, albinism, is a hereditary condition characterised in animals by the absence of pigment in the eyes, skin, hair, scales, feathers or cuticle. This results in an all white animal, usually with pink or red eyes. Melanins and melanin production Melanin is a compound found in plants, animals, and protists, and is derived from the amino acid tyrosine. Melanin is a photoprotectant, absorbing the DNA-damaging ultraviolet radiation of the sun. Vertebrates have melanin in their skin and hair, feathers, or scales. They also have two layers of p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leucism
Leucism () is a wide variety of conditions that result in the partial loss of pigmentation in an animal—causing white, pale, or patchy coloration of the skin, hair, feathers, scales, or cuticles, but not the eyes. It is occasionally spelled ''leukism''. Some genetic conditions that result in a "leucistic" appearance include piebaldism, Waardenburg syndrome, vitiligo, Chédiak–Higashi syndrome, flavism, isabellinism, xanthochromism, axanthism, amelanism, and Melanophilin mutations. Pale patches of skin, feathers, or fur (often referred to as "depigmentation") can also result from injury. Details ''Leucism'' is often used to describe the phenotype that results from defects in pigment cell differentiation and/or migration from the neural crest to skin, hair, or feathers during development. This results in either the entire surface (if all pigment cells fail to develop) or patches of body surface (if only a subset are defective) having a lack of cells that can make pigment. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albinism
Albinism is the congenital absence of melanin in an animal or plant resulting in white hair, feathers, scales and skin and pink or blue eyes. Individuals with the condition are referred to as albino. Varied use and interpretation of the terms mean that written reports of albinistic animals can be difficult to verify. Albinism can reduce the survivability of an animal; for example, it has been suggested that albino alligators have an average survival span of only 24 hours due to the lack of protection from UV radiation and their lack of camouflage to avoid predators. It is a common misconception that all albino animals have characteristic pink or red eyes (resulting from the lack of pigment in the iris allowing the blood vessels of the retina to be visible), however this is not the case for some forms of albinism. Familiar albino animals include in-bred strains of laboratory animals (rats, mice and rabbits), but populations of naturally occurring albino animals exist in the wil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erythrism
Erythrism or erythrochroism refers to an unusual reddish pigmentation of an animal's hair, skin, feathers, or eggshells. Causes of erythrism include: * Genetic mutations which cause an absence of a normal pigment and/or excessive production of others * Diet, as in bees feeding on "bright red corn syrup" used in maraschino cherry manufacturing. Erythrism in katydids has been occasionally observed. The coloring might be a camouflage that helps some members of the species survive on red plants. There is also consensus that the erythristic mutation is actually a dominant trait among katydid species, albeit a disadvantageous one, due to the overwhelmingly green coloration of most foliage. Hence, most pink or otherwise vividly colored katydids do not survive to adulthood, and this observation explains their rarity. Erythrism in leopards is rare, but one study reported that two of twenty-eight leopards seen in camera traps in a South African nature reserve were erythristic, and the autho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pathogenic Fungi
Pathogenic fungi are fungi that cause disease in humans or other organisms. Approximately 300 fungi are known to be pathogenic to humans. Markedly more fungi are known to be pathogenic to plant life than those of the animal kingdom. The study of fungi pathogenic to humans is called "medical mycology". Although fungi are eukaryotic, many pathogenic fungi are microorganisms. The study of fungi and other organisms pathogenic to plants is called plant pathology. ''Candida'' ''Candida'' species cause infections in individuals with deficient immune systems. Th1-type cell-mediated immunity (CMI) is required for clearance of a fungal infection. ''Candida albicans'' is a kind of diploid yeast that commonly occurs among the human gut microflora. ''C. albicans'' is an opportunistic pathogen in humans. Abnormal over-growth of this fungus can occur, particularly in immunocompromised individuals. ''C. albicans'' has a parasexual cycle that appears to be stimulated by environmental stress. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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