EVOLUTION: DARWIN AND BEYOND...

THE ORIGIN OF SPECIES

It is a great honor to introduce the man in the picture above. It might be a sin for me to write about him considering the level he has taken science to. Nevertheless, I do want to take this opportunity and talk about my Idol "CHARLES DARWIN". He is the reason why we all know the term evolution. Darwin’s book "THE ORIGIN OF SPECIES" whose first edition was published on the 7th of January 1860 revolutionized thinking in biology and gave the scientists an incentive to work ahead. Most of the other branches of biology like genetics, cell and molecular biology owe it to Darwin. All of us owe our life to him. If it had not been for him we wouldn’t have understood Natural selection. If it had not been for him we wouldn’t have understood that diseases can be spread from one generation to the other and most importantly we would not understand drug resistance in bacteria. Human discovery in the field of biology in the last century by and large owes it to this great man. Let us now talk about evolution. Today all of us are aware that DNA is the genetic element and that we inherit it from our parents and we pass it on to our offspring’s. We also know that genetic variation and mixing (crossing over) is responsible for the variation we see in our children. But poor Charles Darwin did not know any of that. He did not even know that the variations he observed were because of genes. He wasn’t aware that there was some such thing called DNA. I am saying all this just to emphasize the magnitude of Charles Darwin’s work.

Many of us might ask, IF EVOLUTION IS HAPPENING AROUND US WHY DON’T WE SEE IT? Evolution is happening around us but it is happening at an imperceptible rate. It is similar to the development of science. Human beings have been on earth for the past 4 million years but the most important developments at least in the field of biology have occurred only in the last two centuries. Our life span has increased tremendously in the last two centuries because of our scientific growth. We just don’t realize that this is happening. Similarly, evolution is happening around us and one day it will manifest itself for all of us to see. We already do witness evolution and natural selection in our daily lives. I am sure most of us must have heard of antibiotic resistant strains of bacteria. How do bacteria gain antibiotic resistance? Through mutations or by acquiring genetic resistance through extrachromosomal DNA containing resistance genes commonly called as plasmids. The bacteria that have the extrachromosomal DNA conferring resistance are “NATURALLY SELECTED” to survive despite the administration of the drug. Just like those drug resistant bacteria, human beings are also evolving. Our food habits have evolved; our habitats are different from that of our ancestors. We no longer live in caves and we are in a sense very different from our ancestors in many ways. We will continue to evolve. IS THERE AN END POINT TO EVOLUTION? There are about 30,000 genes in our chromosomes that have been identified. If you consider the permutations and combinations with which these genes can undergo alterations or the possible addition of other genes to this gene pool the evolutionary end point is far, far away. There is no end to evolution. Evolution will only end when all life on earth comes to an end. Thus, evolution is not just man becoming superman. It will not happen perceptibly. It will happen over a period of time and we might not even realize it (scientists will).

That’s all for now… happy evolving.

ROBBIE