Why and how chameleon changes colour?
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Contrary to popular belief, this change of colour is not only an adaptation to the surroundings but also an expression of the physical and physiological condition of the lizard. The skin colour is changed under influence of mood, light and temperature. The skin colour also plays an important part in communication and rivalry fights.\nChameleons have specialised cells that lie in two layers under the chameleon's transparent outer skin. The cells in the upper layer, which are called chromatophores, contain yellow and red pigments. Below these chromatophores is another cell layer. Cells of this layer are called guanophores and they contain the colourless crystaline substance guanin. These guanophores reflect amongst others the blue part of incident light. If the upper layer of chromatophores is yellow, the reflected light becomes green (blue plus yellow). A layer of dark melanin containing melanophores is situated even deeper under these blue and white light reflecting guanophores. These melanophores influence the lightness of the reflected light. All these different pigment cells can relocate their pigments, thereby influencing the colour of light which is reflected.
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Oddly enough there are only two pigments in birds and amphibians two, exactly the same two pigments. Yet we see birds and frogs in every colour of the rainbow. So we really shouldn’t be surprised to see a few bright mammals.\n \nThe way that animals usually generate blue and green colours is by utilising fibres arranged in rows or grids to refract light. That allows the skin to scatter the short blue and green wavelengths back to the observer while absorbing the longer reds. In the case of the mandrill the skin contains rows of collagen fibres designed to achieve exactly that purpose.\n\nThe only other blue mammal I know of is the vervet monkey, which has bright blue testicles. You can see a picture of one in the link below.
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That a polar bear's skin color is actually black is correct. Any discoloring that you have seen may have been to drying or preservation effects on the carcass.
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The point you are talking about is Cape Agulhas.  I have been there and you can see different colors in the water where the oceans meet.  You do not see a perfect horizontal line dividing the oceans, but you do see bands and pockets of color as opposed to the smooth diffusion you might expect.\n\nThe different colors come from different kinds of plankton living in the water.  While it's true that pure water gets its color from refracting light, the ocean is not at all pure.  Plankton living in the water has a major effect on the color of the ocean. The Indian and Atlantic Oceans have different temperatures and different concentrations of salt, so different kinds of plankton live in them. Different kinds of plankton reflect different colors, so when you look at the ocean from the shore you see different colors in the water.\n\nThe bands and pockets of color appear because the oceans don't mix evenly.  The uneven mixture is caused by a current called the Agulhas Retroflection.
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it's reactive to light
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3 questions in one lol.\n\n1.) pigment\n2.) the discolored space is blue and depending on weather/time of day, it will change colors\n3.) Yes. U never asked why.\n\nMy question is how is this a soccer related question lol?
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Actually, this is a really hard one: color arises from light having different frequencies, and the different colors are reflected with varying efficiency from various substances: so a red color arises from a substance that reflects well low frequencies (red) and absorbs higher ones (blue and yellow).\n\nNow what determines in which way a given substance reflects light at different frequencies? That varies a lot: for starters, some atoms *are* in fact colored, that is, they reflect one frequency more  than another: chlorine gas is an example. This is also frequently the case for molecules (dyes). On the other hand, it is also often caused by some effect that cannot be traced back to the individual parts that make up the whole: think of a sand heap: clearly, none of the grains is a heap, nor is there any specific grain which gives the heap its peculiar properties. What makes a sand heap is just the large number of grains, all acting mutually one upon the other. A crowd, similarly, often does things you cannot really explain in terms of the individuals that make it up. Similarly, for example, a large number of copper atoms find a weird way of reflecting certain frequencies much more than others: it is a property of the whole substance that cannot be reduced to the individual copper atoms. Color, by the way, is not at all the only such property.
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I think you are looking at it from the wrong prospective, I wouldnt look at the melanin correlation in chimps or other great apes as to humans. Melanin is the pigment in our skin that helps protect us from the harmful Uv radiation that is present in our everyday lives.\n\n"Dermal melanin is produced by melanocytes, which are found in the stratum basale of the epidermis. Although human beings generally possess a similar concentration of melanocytes in their skin, the melanocytes in some individuals and races more frequently or less frequently express the melanin-producing genes, thereby conferring a greater or lesser concentration of skin melanin. Some individual animals and humans have no or very little melanin in their bodies, which is a condition known as albinism." Wiki. \n\nTherefore, you would see that certain races where melanin was more needed due to their living conditions would have more genes that would express the pigment. If you look at the trend of the globe, enviroments that arent on the poles or on the equator tend to have lighter skinned individuals.Its because they arent getting the direct sunlight/uv radiation that the people on the poles or the equator are getting.\n\nNow there is also the fact that there are different races of human and that these races tend to express pigments very differently from eachother. Such as why chimps are lighter skinned than gorillas... (not exactly a great example, but it will do) over long periods of time natural selection causes fluctuations in these trends, and now that we are seeing increased radiation, those that have stronger forms of melanin and a smaller predisposition to cancer tend to "pass on their genes" or have better reproductive success. Now, this is all relative and I could probably go on for hours about it, but in todays society since we arent nomadic / are particularily sedentary, if you tend to have darker or lighter skin colors it is due to your heratige.
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It's genetic in most people.\n\nThe second main cause is a change in melanin levels in one eye, this can be because of illness or trauma to the head.\n\nFor others a trauma to the head can jolt the blood vessels in the eye causing a change in colour
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This is because when heated, the atom gains energy. The electron in the atom will be excited to a higher energy level. After a while, it would lose the gained energy and release the gained energy in the form of light. Hence, coloured light is produced when they release energy. Some elements only produced certain colour because of the energy required to excite from one state to another are different from other elements. Elements can only be excited from one state to another with specific energy. In other word, the energy is quantised. This is related to the quantum theory. More info can be found on the net and textbook.
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This article )http://www.newscientist.com/article/dn9417-chameleon-snake-can-turn-white-in-minutes-.html) is about the snake discovered in Borneo.  If you search for 'chameleon snake' on yahoo, you'll get a lot of versions of this same story.  \n\nThis wikipedia article (http://en.wikipedia.org/wiki/Chromatophore#Pigment_translocation) talks about pigment translocation, aka physiological color change.  You might be able to find a good journal article in the references at the end.  \n\nThe guy who wrote this article (https://notes.utk.edu/bio/greenberg.nsf/0/16b5f418b10b413f85256a2c0059baf7?OpenDocument) is studying reptile color change in response to stress.  His article, and the ones in his references might help you.\n\nHope one of those helps!
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Without going into the complexities of molecular theory, things APPEAR black because they absorb many wavelengths of visible light/EM radiation including infrared (heat) thus making them hotter.  Because everything is absorbed, no light is reflected and you see no light or darkness/black.  The excess absorbed energy manifests itself in many ways such as adding to the vibration of the molecules or heat.\n\nWITH slightly more detailed quantum theory:\n\nThe energy is absorbed by the electrons of the atoms that make up the black material and excite them from a ground level to a higher level or energy state.   From quantum mechanics, we know that these electrons will only absorb light of a given frequency/energy - that which corresponds to just enough energy to go from level 1 to level 2 to level 3 and so on - and will not absorb other frequencies (hence why we have red - green & blue absorption, etc).  In these black materials it just happens that the differences between all the energy states correspond to most frequencies of visible light giving you dark/black colours or full absorption.  At higher energy states, the atoms and molecules have extra energy which allows them to vibrate more or become hotter.  They're also less stable and reemit this energy in the form of infrared (heat) to get back to the more stable low energy state.
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I think you mean anole lizards. They do change color, but they are definitely NOT chameleons.
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Good question. The colour of a mirror can be affected by the colout of the glass and the colour of the reflective backing. In most mirrors the glass is clear and the backing is silver so they are nominally silver in colour.\n\nOf course this becomes somewhat comlicated when something becomes reflected in them.
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colors become more vibrant
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It's just a color.\n\n\nMaybe they are color blind
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Most male red-headed rock agama lizards are brown speckled, very similar to the females of the species. Only the dominant male of a group (these lizards live groups of 10-20) gains the striking blue blody and red/orange head for which the species is named. \n\nAs to the biological basis of this, agamas have specialized cells imbedded in their outer skin that allow them to change color. In chameleons, these cells may be activated as a result of the animal's physical or psychological state, or in response to the environment (to blend in). In agamas, the cells respond only to the lizard's psychological state, and in the case of the dominant male, this is one of aggression and control. \n\nWere another male in the group to develop similar coloration in response to a change in its psychological state, a fight would immediately ensue, leaving once again only one male with the distinct coloration in the group.