![]() ![]() Melanism is found in many different species, including amphibians, reptiles, and mammals – but not in humans. Melanism (black) results in an excess of dark pigmentation. A leucistic baboon © Tracey Sawyer – read more about this sighting here Melanism The white lions referred to above are also another example of leucism. So, melanin would be present in the skin, beak, legs, eyes and other body parts of a leucistic bird, for example. Leucistic animals and birds do produce melanin (unlike albinos which produce no melanin), BUT the condition prevents melanin from being deposited in the fur or feathers. ![]() Leucines, unlike albino animals, have normal-coloured eyes, and may or may not have normally coloured legs and beaks. Leucism (white) results in a partial or total loss of pigmentation – resulting in patches of white colouring in fur or feathers. A rare albino African civet © Shenton Safaris – read more about this sighting here Leucism Albinism occurs in many species, including humans. Eye colour is also produced by melanin, and so albinos have reddish/pink eyes because the blood vessels show through, not being masked by the darker melanin usually present in eyes. Tyrosinase is a copper-containing enzyme that is needed to produce melanin, the pigment responsible for blacks, grays, browns, rusty browns, and pale yellows of feathers and body parts – and so albinos cannot produce any melanin at all and thus lack any colouration that is caused by the pigment. It is only passed on if both parents transfer it to their offspring.Īlbinism is caused by a genetic mutation causing an absence of tyrosinase in pigment cells. A white lion cub sits among its normal-coloured siblings © Simon Vegter/Wild Wings Safaris Let’s understand the phenomena at play here, in layman’s terms: AlbinismĪlbinism (white) results in whitish-pink fur or feathers, and eyes with reddish pupils (the diagnostics trait). The process of captive breeding of white lions by isolating the gene and producing more white lions than nature would usually produce leads to inbreeding and weak/genetically compromised individual animals that are not suitable for introduction into wild lion populations. Attempts to breed white lions in captivity to ‘save the species’ are misguided and usually all about money – because white lions are popular as caged exhibits and hunting trophies. When it comes to white lions (who are technically leucistic), the white lion gene lives on in the tawny lion population in the Timbavati area of the Greater Kruger National Park, and white individuals will probably keep popping up sporadically – for as long as the tawny lion population there remains stable. A white lion cub © Simon Vegter/Wild Wings Safaris While the occurrence is very rare in the wild, and worth celebrating when seen, claims that ‘white lions’ (for example) are a rare species are incorrect and misleading. ![]() Note that these white or black individuals are not a separate species or subspecies of the normally-coloured animal – they are purely a genetic anomaly. There is something magical about seeing a white lion, black leopard or ‘king’ cheetah in the wild, as if it were a spiritual shadow of the species, a form of higher being. © Brad Francis/Flickr DECODING SCIENCE POST by AG EditorialĮvery now and then nature experiments by producing a black or white mutation of an animal or bird that is otherwise normally coloured. A ‘king’ cheetah’s colouring is an example of pseudo-melanism, also called abundism. ![]()
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