The Wildlife of Black-and-White

The Dark Brown Pigment—Melanin

Let me start this article with someone whom all of you know: A certain ‘Bagheera’. Yes, the ‘black panther’ from Rudyard Kipling’s masterpiece, The Jungle Book. In the book, it is Bagheera who teaches the feral boy (or ‘man cub’) Mowgli about the ‘ways of the jungle’.

You may or may not have seen real-life Bagheeras in your city zoo. The first thing that may have struck you on seeing such an animal is the sheer spectacle: A silky black coat that leaves the onlooker in awe.

It is not surprising that colour leaves us spellbound. And in the case of Bagheera(s), we can draw a parallel with ourselves. So many of the eight billion of us who inhabit this planet have dark-coloured skin. For it is the same dark brown pigment—melanin—that exists in both us and our non-human counterparts, which is responsible for the colour.

Of course, while a black-coloured animal leaves humans in awe, dark-coloured humans have not always drawn a benevolent response. But the emotive concept of race, based on human skin colour, is not the subject of this piece. So, I leave it at that.

Melanism, the excess amount of melanin in skin, fur, scales and feathers, is a phenomenon seen in mammals, birds, amphibians and reptiles. It is rare in humans (Yes. Many of us may be dark. But only very few are ‘truly melanistic’, according to scientists).

What causes it? Well, all of you must have studied about genes, right? They are passed from parents to offspring. They contain the information needed to specify physical and biological traits. A ‘mutation’ can increase the amount of melanin in the skin, fur, scales and feathers.

Some Black-Coloured Animals

Why are some animals black-coloured? Does asking this serve any purpose, you may wonder? It does. Let me give you some examples.

The best instance of melanism is seen in the cat family or felids as the scientists call them. There are almost 40 species of cats, big and small worldwide. They range from the Siberian tiger to your own neighbourhood tabby.

I started with Bagheera, the ‘black panther’. A black panther is actually a variant of both a leopard and a jaguar, who has a gene mutation that causes melanin to cover its rosettes. But even then, “These can be seen at an angle in the bright sun,” wrote Kipling for Bagheera. And since in his imagination the Bagheera belonged to Central India, literally speaking, it should be considered only as a mutation of the Indian Leopard because jaguars are not found in our country at all.

Scientific studies tell us that leopards evolved to be melanistic in thick humid jungle habitats, where such a coat would help hide them and aid them in hunting. A leopard in more open country is unlikely to have a black coat. It is all about natural selection. Hail, Charles Darwin!

But the leopard, which is found in Asia and Africa, is not the only cat that shows melanism. The jaguar does it too. This felid, the third biggest in the cat family after the tiger and lion, is found in the Americas—from Mexico to Argentina. The melanistic jaguar, in some form or the other, was a prominent deity for the Aztec, Maya, Inca and other indigenous American people.

Melanism has been seen in two other big cats also. Bengal tigers in India’s very own Similipal Tiger Reserve (STR) in Odisha exhibit an increased amount of black colour on their coats.

According to Lala A K Singh, an expert on STR’s black tigers, the cats were officially recorded for the first time in the forests of Similipal during 1975–76. That is when forest officials, along with two foreign tourists, saw two full-grown black tigers on the road leading to the Matughar meadow on a bright winter day, according to a report in Gobar Times’ parent publication, Down To Earth (DTE).

Odisha plans to open a safari for these majestic animals. But more on that later.

The African Cheetah also shows melanism in case of some individuals, which are called ‘King Cheetah’. Again, it is not a separate species. In fact, cheetahs and tigers are only partially melanistic or ‘pseudo melanistic’. Only leopards and jaguars are fully or ‘truly melanistic’.

Besides cats, one of the other most well-known instances of melanism is found in the pepper moth of England.

You may remember the Industrial Revolution, having studied about James Watt and his steam engine? Now let me tell you a backstory about it.

The pepper moth usually had light coloured wing patterns. This provided them with effective camouflage. But when the Industrial Revolution began, the spike in the use of coal led to deposition of soot everywhere in England. The light moths began to be increasingly predated upon by birds.

It is then that, according to scientists, the moths evolved completely black coloured wings. This strategy paid off. The black moths were now indistinguishable from their new surroundings and hence would not be visible as easily to their predators. Scientists have called this phenomenon as ‘industrial melanism’.

Having covered mammals and insects, let me come to birds next. The best instance of a melanistic bird from India is the Kadaknath poultry breed. You may have come across media reports about this unique breed of chicken that originates in Jhabua, Madhya Pradesh.

It is completely black in colour—comb, wattle, beak and feathers. Even its flesh is black due to the presence of melanin. But don’t worry. The meat is thought to be more nutritious than the ordinary broiler you may eat. Indeed, the Government of India is supporting programmes to help Adivasis breed Kadaknath and help their local economies.

The Silkie from China and Ayam Cemani from Indonesia are similar to the Kadaknath in that they exhibit melanism as well. Check out their photos on the net.

A Colourless phenomenon—Albinism and Leucism

Melanistic animals may leave you in awe. But it is not the only genes-based colour phenomenon in the animal kingdom. There is also albinism and leucism.

Now what are these? You may have heard about albinism before. There are albino humans too. Simply put, albinism is the loss of melanism from the human body. An albino animal or human usually has white skin, fur, feathers. Their eyes are usually reddish-pink as the absence of pigment causes the retina’s red blood vessels to be reflected.

Leucism, on the other hand, is the partial loss of pigmentation in animals. Such animals may appear white. But their eyes are normal coloured.

Leaving a Colourful Impression

What does this deep dive into the colours of the natural world tell us? For one, it shows us how animals have evolved over millennia to develop features—as in melanism—that help them make best use of their habitat.

The Odisha government’s decision to setup a safari for STR’s black tigers evoked mixed responses from conservationists. Some lauded the move. Displaying such rare animals to tourists would create awareness about them and aid in their conservation, Singh told DTE. Others, though, were critical. We should let such beautiful, rare animals range free in the wild, their home.

While the jury is still out on this, one thing is for sure: Colour, whether in humans or animals, does leave an impression. It is Nature, that greatest of crafts persons, at its best. We humans are nothing before it. That should give us lessons in humility. Wouldn’t you agree?