Toad Tuesday

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A melanistic jaguar at the Henry Doorly Zoo. Melanism is the result of a dominant alleleand is relatively common in jaguars.

A melanistic Indian leopard in Nagarhole National Park

A black panther is the melanistic color variant of any big cat species. Black panthers in Asia and Africa are leopards (Panthera pardus), and those in the Americas are black jaguars (Panthera onca).^[1][2]

Contents

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• 1Melanism
• 2Leopard
  • 2.1In captivity
• 3Jaguar
• 4Cougar
• 5Reports
• 6Pseudo-melanism
• 7Culture and literature
• 8See also
• 9References
• 10External links

Melanism

Melanism in the jaguar (Panthera onca) is conferred by a dominant allele, and in the leopard (Panthera pardus) by a recessiveallele. Close examination of the color of these black cats will show that the typical markings are still present, but are hidden by the excess black pigment melanin, giving an effect similar to that of printed silk. This is called "ghost striping". Melanistic and non-melanistic animals can be littermates. It is thought that melanism may confer a selective advantage under certain conditions since it is more common in regions of dense forest, where light levels are lower.^{[citation needed]} Recently, preliminary studies also suggest that melanism might be linked to beneficial mutations in the immune system.^[3]

Leopard

A melanistic leopard

Melanism is relatively common in leopards, with melanistic individuals making up approximately 11% of the species, occurring at very different rates in different subspecies with non-random distribution.^[4]

Data on the distribution of leopard populations indicates that melanism occurs in five subspecies: Javan leopard (P. p. melas), African leopard (P. p. pardus), Indian leopard (P. p. fusca), Indochinese leopard (P. p. delacouri) and Sri Lankan leopard (P. p. kotiya). Black leopards are common in the equatorial rainforest of Malaya and the tropical rainforest on the slopes of some African mountains such as Mount Kenya.^[5] They are also common in Java, and are reported from densely forested areas in southwestern China, Myanmar, Assam and Nepal, from Travancore and other parts of southern India where they may be more numerous than spotted leopards.^[6] One was recorded in the equatorial forest of Cameroon.^[7]

In captivity

Markings on a female black leopard

The taxonomic status of captive black leopards and the extent of hybridization between different subspecies is uncertain. Therefore, coordinated breeding programs for black leopards do not exist in European and North American zoos.^[8] Black leopards occupy space needed for breeding of endangered leopard subspecies and are not kept within the North American Species Survival Plan.^[9][10]

Jaguar

A melanistic jaguar

In jaguars, the melanism allele is dominant. Consequently, black jaguars may produce either black or spotted cubs, but a pair of spotted jaguars can only produce spotted cubs. Individuals with two copies of the allele are darker (the black background colour is more dense) than ones with just one copy, whose background colour may appear to be dark charcoal rather than black.

The black jaguar was considered a separate species by indigenous peoples. English naturalist W. H. Hudson wrote:

The jaguar is a beautiful creature, the ground-colour of the fur a rich golden-red tan, abundantly marked with black rings, enclosing one or two small spots within. This is the typical colouring and it varies little in the temperate regions; in the hot region the Indians recognise three strongly marked varieties, which they regard as distinct species – the one described; the smaller jaguar, less aquatic in his habits and marked with spots, not rings; and, thirdly, the black variety. They scout the notion that their terrible "black tiger" is a mere melanic variation, like the black leopard of the Old World and the wild black rabbit. They regard it as wholly distinct, and affirm that it is larger and much more dangerous than the spotted jaguar; that they recognise it by its cry; that it belongs to the terra firma rather than to the water-side; finally, that black pairs with black, and that the cubs are invariably black. Nevertheless, naturalists have been obliged to make it specifically one with Felis onca [Panthera onca], the familiar spotted jaguar, since, when stripped of its hide, it is found to be anatomically as much like that beast as the black is like the spotted leopard.^[11]

A black jaguar named "Diablo" was inadvertently crossed with a lioness named "Lola" at the Bear Creek Wildlife Sanctuary in Barrie, Ontario, Canada.^[12] The offspring were a charcoal black jaglion female and a tan-coloured, spotted jaglion male. It therefore appears that the jaguar melanism gene is also dominant over normal lion colouration (the black jaguar sire was presumably carrying the black on only one allele). In preserved, stuffed specimens, black leopards often fade to a rusty colour but black jaguars fade to a chocolate brown colour