Will Burrard-Lucas / Young male melanistic leopard (Panthera pardus), Laikipia Wilderness Camp, Kenya. Photographed with a camera trap. EDITORIAL USE ONLY. All other uses require clearance

Will Burrard-Lucas / Young male melanistic leopard (Panthera pardus), Laikipia Wilderness Camp, Kenya. Photographed with a camera trap. EDITORIAL USE ONLY. All other uses require clearance

Will Burrard-Lucas / Young male melanistic leopard (Panthera pardus), Laikipia Wilderness Camp, Kenya. Photographed with a camera trap. EDITORIAL USE ONLY. All other uses require clearance

Will Burrard-Lucas / Young male melanistic leopard (Panthera pardus), Laikipia Wilderness Camp, Kenya. Photographed with a camera trap.

Giri Cavale / Melanistic leopard / Black panther (Panthera pardus) Nagarahole National Park, Nilgiri Biosphere Reserve, Karnataka, India.

Giri Cavale / Melanistic leopard / Black panther (Panthera pardus) on territorial patrol on track, Nagarahole National Park, Nilgiri Biosphere Reserve, Karnataka, India.

Cyril Ruoso / Bengal Tiger (Panthera tigris tigris) white adult resting, native to Asia

Edwin Giesbers / Close up head portrait of melanistic / black Leopard (Panthera pardus) captive

Rod Williams / Female Geoffroy's cat {Felis geoffroyi}. Rare melanistic form. Captive.

Lynn M Stone / Melanistic (black form) leopard snarling, often called black panther (captive)

Felis Images / Melanistic leopard / Black panther (Panthera pardus fusca) sitting, reflected in water. Nagarhole National Park, India. Photo Phillip Ross/Felis Images

Felis Images / Melanistic leopard / Black panther (Panthera pardus fusca) drinking, reflected in water. Nagarhole National Park, India. Photo Phillip Ross/Felis Images

Felis Images / Melanistic leopard / Black panther (Panthera pardus fusca) resting in tree. Nagarhole National Park, India. Photo Phillip Ross/Felis Images

Felis Images / Melanistic leopard / Black panther (Panthera pardus fusca) resting in tree. Nagarhole National Park, India. Andhra Pradesh, India. Photo Srikanth GP/Felis Images

David Tipling / Rare melanistic Grey seal (Halichoerus grypus) pup, Horsey, Norfolk, England, UK, February. Less than one in 400 pups born annually are melanistic, usually the pups are a creamy white in colour.

David Tipling / Rare melanistic Grey seal (Halichoerus grypus) pup, Horsey, Norfolk, England, UK, February. Less than one in 400 pups born annually are melanistic, usually the pups are a creamy white in colour.

David Tipling / Rare melanistic Grey seal (Halichoerus grypus) pup, Horsey, Norfolk. Less than one in 400 pups born annually are melanistic, usually the pups are a creamy white in colour.

Robert Valentic / Green Tree Snake (Dendrelaphis punctulatus) melanistic form, Melaleuca swampland, Mackay, Queensland coast. Australia. Dry season.

Stefan Christmann / Emperor penguin (Aptenodytes forsteri), pair within breeding colony in courtship, male melanistic. Atka Bay, Antarctica. May.

Stefan Christmann / Emperor penguin (Aptenodytes forsteri) with melanism in breeding colony, male melanistic. Atka Bay, Antarctica. May.

Stefan Christmann / Emperor penguin (Aptenodytes forsteri), melanistic male in breeding colony, portrait. Atka Bay, Antarctica. May.

Stefan Christmann / Emperor penguin (Aptenodytes forsteri), melanistic male amongst others in breeding colony. Atka Bay, Antarctica. May.

Stefan Christmann / Emperor penguin (Aptenodytes forsteri), melanistic male, portrait. Atka Bay, Antarctica. May.

Kerstin Hinze / Melanistic Common dormouse (Muscardinus avellanarius) resting on a branch, September. Captive

Bruno D'Amicis / Melanistic Asp viper (Vipera aspis) moving between the roots of ancient tree in old growth Beech (Fagus sylvatica) forest. Abruzzo, Lazio and Molise National Park / Parco Nazionale d'Abruzzo, Lazi...

Will Burrard-Lucas / Short film describing how photographer Will Burrard-Lucas photographed a melanistic Leopard (Panthera pardus), showing camera trap set-up, near Laikipia Wilderness Camp, Sosian Game Ranch, Kenya, Febr...

Sandesh Kadur / Melanistic Leopard / Black panther (Panthera pardus) male in tree, Nagarahole National Park, Nilgiri Biosphere Reserve, Karnataka, India.

Giri Cavale / Melanistic leopard / Black panther (Panthera pardus) on territorial patrol on track, Nagarahole National Park, Nilgiri Biosphere Reserve, Karnataka, India.

Giri Cavale / Melanistic leopard / Black panther (Panthera pardus) male, Nagarahole National Park, Nilgiri Biosphere Reserve, Karnataka, India.

Giri Cavale / Melanistic leopard / Black panther (Panthera pardus) male in tree, Nagarahole National Park, Nilgiri Biosphere Reserve, Karnataka, India.

Giri Cavale / Melanistic leopard / Black panther (Panthera pardus) male in tree, Nagarahole National Park, Nilgiri Biosphere Reserve, Karnataka, India.

Giri Cavale / Melanistic leopard / Black panther (Panthera pardus) on territorial patrol on track, Nagarahole National Park, Nilgiri Biosphere Reserve, Karnataka, India.

Giri Cavale / Leopard (Panthera pardus) male chasing away a melanistic leopard / black panther, Nagarahole National Park, Nilgiri Biosphere Reserve, Karnataka, India.

Felis Images / Leopard (Panthera pardus) spotted male with melanistic female resting on rocks, Tamil Nadu, Western Ghats, India.

Edwin Giesbers / Black panther / melanistic Leopard (Panthera pardus) female with normal spotted cub, captive.

Edwin Giesbers / Black panther / melanistic Leopard (Panthera pardus) female with normal spotted cub, captive.

Edwin Giesbers / Black panther / melanistic Leopard (Panthera pardus) baring teeth, captive.

Edwin Giesbers / Black panther / melanistic Leopard (Panthera pardus) baring teeth, captive.

Edwin Giesbers / Black panther / melanistic Leopard (Panthera pardus) portrait, captive.

Edwin Giesbers / Black panther / melanistic Leopard (Panthera pardus) female with normal spotted cubs playing, captive.

Edwin Giesbers / Black panther / melanistic Leopard (Panthera pardus) female resting with normal spotted cub, captive.

Edwin Giesbers / Black panther / melanistic Leopard (Panthera pardus) portrait, captive.

Edwin Giesbers / Black panther / melanistic Leopard (Panthera pardus) female with normal spotted cub suckling, captive.

Edwin Giesbers / Black panther / melanistic Leopard (Panthera pardus) portrait, captive.

Dave Watts / Black panther / melanistic Leopard (Panthera pardus) portrait. captive.

Dave Watts / Black panther / melanistic Leopard (Panthera pardus) portrait. captive.

Dave Watts / Black panther / melanistic Leopard (Panthera pardus) portrait, licking muzzle, captive.

Dave Watts / Black panther / melanistic Leopard (Panthera pardus) portrait, licking muzzle, captive.

Andy Rouse / Black panther / melanistic Leopard (Panthera pardus) snarling. Captive. Non-ex

Andy Rouse / Black panther / melanistic Leopard (Panthera pardus) snarling. Captive. Non-ex

Andy Rouse / Black panther / melanistic Leopard (Panthera pardus) on log, captive. Non-ex

Andy Rouse / Black panther / melanistic Leopard (Panthera pardus) running, blurred motion. Captive. Non-ex

Andy Rouse / Black panther / melanistic Leopard (Panthera pardus) running, blurred motion. Captive. Non-ex

Andy Rouse / Black panther / melanistic Leopard (Panthera pardus) standing on dead tree, captive. Non-ex

Andy Rouse / Black panther / melanistic Leopard (Panthera pardus) standing on dead tree, captive. Non-ex

Phil Savoie / Tree bumblebee (Bombus hypnorum) melanistic form, Wales UK, June.

Edwin Giesbers / Leopard (Panthera pardus) cub suckling from a melanistic parent. Captive.

Edwin Giesbers / Portrait of a melanistic Leopard (Panthera pardus), opening and closing eyes. Captive.

John Cancalosi / Red-eared slider, (Trachemys scripta) in water, old melanistic individual, Maryland, USA, August.

John Cancalosi / Red-eared slider, (Trachemys scripta) in water, old melanistic individual, Maryland, USA, August.

Dave Bevan / Melanistic male Fallow deer (Dama dama) in woodland, panting and drinking from a puddle, Carmarthenshire, Wales, UK. October.

Dave Bevan / Melanistic male Fallow deer (Dama dama) in woodland, panting and drinking from a puddle, Carmarthenshire, Wales, UK. October.

Dave Bevan / Melanistic male Fallow deer (Dama dama) feeding in woodland, shakes antlers in dead bracken fronds, Carmarthenshire, Wales, UK. October.

Dave Bevan / Melanistic Common rabbit (Oryctolagus cuniculus) grazing, Pembrokeshire, Wales, UK. April.

Juan Carlos Munoz / Grey wolf (Canis lupus) melanistic morph, captive.

Juan Carlos Munoz / Grey wolf (Canis lupus) melanistic morph, captive.

David Pattyn / Red squirrel (Sciurus vulgaris) with melanistic fur in deep snow, Crans Montana, the Alps, Wallis, Switzerland. February

David Pattyn / Red squirrel (Sciurus vulgaris) with melanistic fur on a tree trunk in a snow covered forest, Crans Montana, the Alps, Wallis, Switzerland. February

David Pattyn / Red squirrel (Sciurus vulgaris) with melanistic fur on a tree trunk in a snow covered forest, Crans Montana, the Alps, Wallis, Switzerland. February

David Pattyn / Red squirrel (Sciurus vulgaris) melanistic morph foraging in deep snow, Crans Montana, the Alps, Wallis, Switzerland. February

David Pattyn / Red squirrel (Sciurus vulgaris) melanistic morph in deep snow, Crans Montana, the Alps, Wallis, Switzerland. February

Andres M. Dominguez / Melanistic rabbit (Oryctolagus cuniculus) with normal European rabbits in grassland, Edinburgh, Scotland, UK, July.

Nick Upton / Melanistic rescued Grey seal pup (Halichoerus grypus) 'Badger' in a convalescence pool where it will be kept until strong enough to be released back to the sea, Cornish Seal Sanctuary, Gweek, Cornwall...

Dong Lei / Mountain apollo butterfly (Parnassius apollo) melanistic form, Yunnan, China. July. Vulnerable species.

Martin Gabriel / Aesculapian snake (Zamenis longissimus) melanistic form, Krk Island, Croatia, June.

Michael Hutchinson / European adder (Vipera berus) melanistic in dry bracken, Gloucestershire, UK, March.

Roland Seitre / Melanistic Jaguar (Panthera onca) portrait. Captive, occurs in Central and South America.

Roland Seitre / Melanistic Jaguar (Panthera onca) portrait with mouth open. Captive, occurs in Central and South America.

Roland Seitre / Melanistic Jaguar (Panthera onca) portrait. Captive, occurs in Central and South America.

Philippe Clement / Black / melanistic jaguar (Panthera onca) with spots still visible, Cabarceno Park, Cantabria, Spain. Captive, occurs in Central and South America.

Philippe Clement / Black / melanistic jaguar (Panthera onca) with spots visible, lying in the grass, Cabarceno Park, Cantabria, Spain. Captive, occurs in Central and South America.

Roland Seitre / Jaguar (Panthera onca) melanistic individual, also called a black panther, native to Central and South America

Roland Seitre / Jaguar (Panthera onca) melanistic individual, also called a black panther, native to Central and South America

Roland Seitre / Jaguar (Panthera onca) melanistic individual, also called a black panther, native to Central and South America

Roland Seitre / Jaguar (Panthera onca) melanistic individual, also called a black panther, native to Central and South America

Roland Seitre / Jaguar (Panthera onca) melanistic individual, also called a black panther, native to Central and South America

Luis Quinta / Female Baskian viper (Vipera seoanei) with melanistic coloration on rock, Geres National Park (Parque Nacional Peneda-Geres ), Portugal, October.

Luis Quinta / Female Baskian viper (Vipera seoanei) with melanistic coloration on rock, Geres National Park (Parque Nacional Peneda-Geres ), Portugal, October.

Luis Quinta / Female Baskian viper (Vipera seoanei) with melanistic coloration on rock, Geres National Park (Parque Nacional Peneda-Geres ), Portugal, October.

Luis Quinta / Female Baskian viper (Vipera seoanei) with melanistic coloration on rock, Geres National Park (Parque Nacional Peneda-Geres ), Portugal, October.

Bertie Gregory / Vancouver island grey wolf (Canis lupus crassodon) melanistic form, walking on a beach, Vancouver Island, British Columbia, Canada, July.

Steve Gettle / Gray Wolf (Canis lupus) pair including melanistic individual, North America