AmelanismPreviously I wrote about melanism (tmblr.co/Zyv2JsYpZGm-qa00), amelanism also exist

AmelanismPreviously I wrote about melanism (https://tmblr.co/Zyv2JsYpZGm-qa00), amelanism also exists and is characterised by a lack of melanin pigments (making it the opposite of melanism). Melanin is a pigment produced from an amino acid by a melanosome. Amelanism can affect a range of animals including fish, mammals, birds, and amphibians. However, difficulty in producing melanins affects these groups of animals differently.In mammals, if a melanosome is unable to produce melanin, no pigment is produced. As such, the mammal has white hair, pink skin, and pink, red, or violet eyes. Hair is affected by the lack of melanin, as in a normally functioning melanosome, melanin is produced and then engulfed by a cell. When this cell happens to be at the root bulb of a hair, the hair takes up the melanin pigment.A complete failure of the enzyme that allows production of melanin an organism produces a condition called albinism, where there is no pigment in skin, hair, eyes, or anything else. However, this condition is particularly rare in nature as it is difficult for organisms with this mutation to survive; many organisms instead have varying degrees of amelanism, where only one portion of a body is lacking pigment.In other vertebrates such as fish, birds, and amphibians, things happen a little differently. These vertebrates produce a wider range of pigments via chromatophores (for example xanthophores produce yellow pigment, erythrophores produce orange pigment, and cyanophores produce blue pigment). Therefore a lack of melanin affect pigmentation differently, so amelanistic vertebrates are less likely than mammals to have pale skin and red eyes.~SAImage: http://bit.ly/1gl4Qob -- source link

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