And because this amazing species has reached its endangered status, the Indian government has taken measures to preserve them. There are 48 tiger reserves in India taken care of by Project Tiger ( a tiger conservation initiative) and did you know 70% of the tigers of the world are in India. I take immense pride. There are like some 6 subspecies of tigers prevalent today itseems. And the initiative takes care to preserve them.
Talking of subspecies and stuff, have you guyz seen the white tiger? That's a real beauty too you know! Imagine, the mere lack of colour gives him a distinct aura of mystery. Isn't it. I remember seeing him for the first time in the Zoo in Hyderabad and was totally fascinated. That must have been like 18 years back.
All my life I assumed white tigers were the albino counterparts of the normal majestic orange tigers. And that it is something that happened by chance in nature. But now, recently, a week back, I read ( from where else, my son's animal book ) that white tigers are not albinos. Albino indicates the complete lack of pigment it seems, and because these tigers do still adorn the black stripes, their condition is called leucistic, (a partial lapse of pigments) . The lapse is because of a particular gene and is hereditary.
And in the forest, this happens only one in 10,000 tigers. Why, simply because, nature doesn't encourage the white tigers. For a good reason. The cubs born with this genetic mutation are at an evolutionary disadvantage because they have lost their ability to camouflage or blend in with the surroundings. So, when they are born in the wild, mostly they die at young age, either because they are hunted down easily or because of the number of health problems that come along with leucism. And as they die young, they don't live long enough to pass it on to their children. Thus is nature's way of eliminating something that is disadvantageous to the species. Amazing isn't it!
But, humans have a way to meddle with nature. We always do. We call it advancement of mankind! One king spotted this white tiger in the forest and as all kings have a habit of collecting rare things, captured this tiger. And he went on to breed this tiger with a normal orange tiger. Thus passing on the gene. (Apparently, this white gene is present in the Bengal Tigers. When the king gifted it to the US, they let it breed with Siberian Tigers. Most of the white tigers we see today is a crossbreed.)
A brief introduction to genetics will tell us why this whole white tiger breeding this is a disadvantage or an err to the species. Every(mostly, with a few exceptions) cell contains nucleus containing chromosomes. The number of chromosomes present in the cell depend on the species. Like humans have 23 pairs. The animals might have more or even less. What is important is , these chromosomes, contain something called DNA which control our traits. And during breeding or reproduction one of each pair of chromosomes are passed on from the parent to the child. That is to say, in humans, father has 23 pairs of chromosomes that define him and the mother has 23 pairs. They both pass on one of each pair, that is, 23 chromosomes each to the baby. So the baby shares both their traits. 23 from the father and 23 from the mother.
Some genes are recessive and some are dominant. Recessive meaning, if child has acquired the same gene from both parents, only then that trait would be displayed. Example is the green/blue eyes gene. Only if the blue eye gene is acquired from both the parent, the child will have blue eyes. Dominant gene is the one responsible for brown eye color. If the child acquires one brown eye gene from a parent, she/he gets the brown eyes.
The gene responsible for the white colour is a double recessive gene. Meaning has to be acquired from both the parents to be displayed in the cub. Which is also why it was rare in the wild. The king who captured the white tiger in the wild, allowed it to produce offsprings, all normal coloured, with a normal orange tiger. Later, he again mated the white tiger with one of the cubs thus produced. Now this cub would've carried one copy of the white gene. Mated with the white tiger, it produced 4 white cubs. The king was excited and he gifted two to the American National Zoo. Imagine how valued the gift must have been that day when no one had seen a white tiger ever.
The zoo got popular and the king got encouraged to make more of these. The process of breeding within the family is called inbreeding and this has a big fall side. Along with the white gene, inbreeding encourages the passing on of the other recessive or deleterious traits to the offspring. Apart from the other diseases that spread because of inbreeding, the white gene is associated with cross-eyed trait. That is, all white tigers are cross eyed (whether it is seen or not). That is the optic nerve is wired to the wrong side of the brain. Many cubs are born still, many are deformed.. oh the cruel/sad list never ends. I'm going to paste the list of deformities thus resulting from this very informative website right here.
A variety of birth defects are associated with the allele for leucism, including crossed eyes, cleft palate, spinal deformities, club foot, immune deficiencies, heart and kidney defects, hip dysplasia, hind-limb paralysis and mental disabilities. The practice of inbreeding generations of lions and tigers to produce leucism makes all the offspring (not just the rare white ones) more likely to suffer from this myriad of congenital illnesses and defects.
In addition, inbreeding increases the chances of stillbirths and infant mortalities, especially with further inbred generations. According to Big Cat Rescue, about eight in 10 white tigers die from inbreeding-related birth defects, and even the survivors tend to exhibit severe deformities and die young. Because they are so heavily inbred and almost always documented in captivity, white tigers and lions are also more likely to suffer from depression.
Now, isn't that sad. Brace yourselves, I'm going to tell you even worse stuff. Apparently, earlier, in certain parts of Africa, certain companies organized hunting trips for interested people. And the price of the experience or the trip depended on what animals were available to be hunted. For instance, if the package included hunting white lions/tigers, the price shot over the roof. And these companies employed breeders to breed these white animals just to have them shot!! Luckily, the African government intervened and I hear these operations are banned now.
The other place where breeding white tigers paid off was at the zoo. People thronged the zoos just to catch a glimpse of these white tigers and the cute cuddly white cubs. Little did we know the immense suffering they have to go through all their life. Let's take a vow to spread the word. Out of every ten tigers that result from inbreeding, only 2 survive (for a while). The other 8 that are born ill, or born with deformities, are either killed or discarded because they don't fetch the bucks. And it doesn't stop here, out of the every 30 white tigers that are 'made', only 1 survives for quite some time. Do the math. Save the tigers. Not only is this sad for the white tigers, it also results in keeping the white gene still in the gene pool and preventing the white gene (the gene associated with deformities/sickness) from getting erased away, thereby reducing the survivability of the entire species.
I also read that the tiger species are endangered now. And are slowly getting erased away from the world. Due to million other reasons. And someone says, it might so happen that in the future, the only tigers we see are the ones in captivity. But the ones in captivity we have are all from the bad gene pool. Eventually resulting in extinction.
Maybe the people back then didn't have much of an information about genes, mutation, recessive genes and stuff. We do. We understand. Maybe all they thought was to protect this white tiger which they thought was a species in itself. Sadly, it isn't a species. So it doesn't need saving. The nature is trying hard to protect the tigers from going extinct. Nature is trying hard to let the tigers be strong enough to survive. Let's join hands with the nature, and say no to white tigers when we see them. Let the poor thing live its life. It's our national animal after all. Let's protect it and treat it with the respect it deserves!
Some amazing websites :
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