The black jaguar animal is black due to melanism. Melanism is an increased amount of black or very dark pigmentation, and it occurs not only in jaguars, but in many other living creatures too. When a black jaguar animal is killed and stuffed, its coat tends to fade into a chocolate brown shade, while stuffed black leopards usually develop a rusty coloration. Melanism is common in many cat species, especially leopards (Panthera pardus) and jaguars (Panthera onca). In leopards it is caused by a recessive gene mutation, while it is caused by a dominant gene mutation in jaguars. Since the gene mutation causing melanism is dominant in jaguars, a black jaguar animal can produce black as well as yellow offspring, while two yellow jaguars never will produce black offspring. Two yellow leopards can on the other hand produce black leopards, as long as both parents carry the recessive gene for melanism. The high occurrence of melanism in cat species indicates that it is probably a positive mutation in some environments. The black jaguar animal is more common in dense jungle habitats than in more open and dry regions where the sandy coloration is to be preferred. Since the jaguar is a nocturnal species that hunts when light is scarce, a black coloration is however probably not very disadvantageous even in a dryer environment, and the black jaguar animal can do well even in such habitats. Melanism has also been linked to beneficial mutations of the immune system. We know of at least one leopard population in Malaysia where up to 50 percent of the cats are black due to melanism. In addition to the black jaguar animal, you can also encounter white jaguars in South America. Unlike the black jaguar animal, the white jaguar animal is extremely rare – probably due to the fact that the white coating is less beneficial than the spotted or black coating. A white jaguar is either an albino jaguar or a leucistic jaguar. Unlike the albino jaguar, a leucistic jaguar will have normally coloured eyes. Albinism is caused by a total lack of melanin, while a leucistic jaguar have the necessary melanin in its pigment cells but lack an enzyme necessary to activate it. White jaguars have been reported from Paraguay, where they are known as Ghost Jaguars.
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