One of the most interesting things present in animals. This is called genetic imprinting.
Have you ever imagined why a kangaroo baby always reaches for her mother's pouch just after it is born? I mean how does it even know that her mother is sitting outside him/her? Its all imprinted in its brain. Its an evolutionary tactics which developed over the years. And when I say years, it means centuries of centuries or even more!
Also, the best remarkable example of genetic imprinting can be seen in an episode of the cartoon of Tom and Jerry, where the famous duckling(i forgot its name) hatches out of the egg, and follows Tom throughout the episode. Thats what ducks do. They consider the biggest moving object they first see as their mother, and will follow it all the time, even if its a robot. It is also seen in chicks(pun not intended).
Now, as we say it developed by evolution, how? I mean, it just didnt happen suddenly, and all became just like that. Evolution can be explained in many different theories. It is simply logical and mathematical.
One of the theories for the ducks can be considered as follows: Genetic changes happens sometimes, ie genetic characteristic in an offspring may shift from their parental characteristic to a new one, or they might show some new behavior, which after generations, becomes imprinted on the genes. The probability of this happening(sudden change in behaviour) is very low. Now, suppose in one of them, the offspring tends to follow her mother just after it is born. And it is seen that due to some reasons, it had more chance of surviving, and does survive, whereas other dies. So, the offspring with such behaviors survive, and others die. Or we can say, to be more accurate, the rate of the 'offspring with behavior dying' is more than that of which doesnt have it. Hence, its genes strives, and this is now common in every offspring. Even now, some ducklings might not show this behavior, and hence, it wont become a healthy adult, or may be eaten by a predator before. So, its modified gene will not be included in the gene pool. Hence, the words "Survival of the fittest."
Now what happens if, by any situation, the offspring with the tendency of following its mother faces the threat of dying more than the counter behavior? Then two thing can happen:
1>Either the whole duck family will go in the verge of extinction
2>Or luckily, if any offspring with the counter tendency shows up, and can multiply, that previous known behavior will be completely reversed.
You can even take the first cry of a baby as a genetic imprinting. Those babies, who after being born, cried for air, survived, and those who didnt, didnt. But now that medical science has advanced so much, such a child who doesnt breathe can be made to live. This is the reason why earlier, humans, or homo erectus, or any of our earlier ancestors, were healthy, and now, our gene pool is polluted as such unhealthy child survives.
But, on the sunny side, this is a primary difference between the homo sapiens and the rest of our ancestors. We now have evolutionary advantage by our mind, and not by our strength. Hence, survival of such a child doesnt really hamper our development. We dont require peak physical fitness any more, we require human resource. And thats partly why, slowly, homo sapiens have developed such a large cerebrum.
PS: If you can carefully care a duck or hen egg and can hatch it, you will find yourself a true best friend, who follows you even to death! (As for the offspring, it will see you as its mother!)
Have you ever imagined why a kangaroo baby always reaches for her mother's pouch just after it is born? I mean how does it even know that her mother is sitting outside him/her? Its all imprinted in its brain. Its an evolutionary tactics which developed over the years. And when I say years, it means centuries of centuries or even more!
Also, the best remarkable example of genetic imprinting can be seen in an episode of the cartoon of Tom and Jerry, where the famous duckling(i forgot its name) hatches out of the egg, and follows Tom throughout the episode. Thats what ducks do. They consider the biggest moving object they first see as their mother, and will follow it all the time, even if its a robot. It is also seen in chicks(pun not intended).
Now, as we say it developed by evolution, how? I mean, it just didnt happen suddenly, and all became just like that. Evolution can be explained in many different theories. It is simply logical and mathematical.
One of the theories for the ducks can be considered as follows: Genetic changes happens sometimes, ie genetic characteristic in an offspring may shift from their parental characteristic to a new one, or they might show some new behavior, which after generations, becomes imprinted on the genes. The probability of this happening(sudden change in behaviour) is very low. Now, suppose in one of them, the offspring tends to follow her mother just after it is born. And it is seen that due to some reasons, it had more chance of surviving, and does survive, whereas other dies. So, the offspring with such behaviors survive, and others die. Or we can say, to be more accurate, the rate of the 'offspring with behavior dying' is more than that of which doesnt have it. Hence, its genes strives, and this is now common in every offspring. Even now, some ducklings might not show this behavior, and hence, it wont become a healthy adult, or may be eaten by a predator before. So, its modified gene will not be included in the gene pool. Hence, the words "Survival of the fittest."
Now what happens if, by any situation, the offspring with the tendency of following its mother faces the threat of dying more than the counter behavior? Then two thing can happen:
1>Either the whole duck family will go in the verge of extinction
2>Or luckily, if any offspring with the counter tendency shows up, and can multiply, that previous known behavior will be completely reversed.
You can even take the first cry of a baby as a genetic imprinting. Those babies, who after being born, cried for air, survived, and those who didnt, didnt. But now that medical science has advanced so much, such a child who doesnt breathe can be made to live. This is the reason why earlier, humans, or homo erectus, or any of our earlier ancestors, were healthy, and now, our gene pool is polluted as such unhealthy child survives.
But, on the sunny side, this is a primary difference between the homo sapiens and the rest of our ancestors. We now have evolutionary advantage by our mind, and not by our strength. Hence, survival of such a child doesnt really hamper our development. We dont require peak physical fitness any more, we require human resource. And thats partly why, slowly, homo sapiens have developed such a large cerebrum.
PS: If you can carefully care a duck or hen egg and can hatch it, you will find yourself a true best friend, who follows you even to death! (As for the offspring, it will see you as its mother!)
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