Can Smokers be Wiped out by Natural Selection?

One interesting thought!! Can Natural Selection wipe out the smokers from the Earth after years of evolution? The study results point to a similar direction.

First of all, the smoking habit has to be a genetic characteristic (inherited property in other words) to be qualified to take part in evolution. Scientists, in fact, claim to have discovered the gene linked to smoking habit. The study by Dr Hidetoshi Nakamura of Keio University in Japan looked at a particular gene known to have an effect on how people process nicotine. In the human body, nicotine is mainly metabolized by the gene CYP2A6.If people are not very good at processing nicotine, then they are less likely to be interested in smoking and less likely to continue if they do start. In another study by Dr Robert Walton, of Oxford's clinical pharmacology department, variations of a gene known as the dopamine D2 receptor gene, or DRD2, reveals whether individuals are genetically programmed to be addicted to nicotine. One in three people is born with the gene.

Now let's see how the smoking habit can make us disadvantageous to reproduce. British researchers published a study claiming that a life of cigarette smoking will be, on average, 10 years shorter than a life without it. They also claimed that consistent cigarette smoking doubles mortality rates in both middle age and old age. More interestingly, Men who smoke cigarettes may experience a significant decline in their capacity to father a child, a research by a reproductive medicine specialist from the University at Buffalo indicates. Like other cells in the body, human sperm carry a receptor for nicotine, which means they recognize and respond to nicotine. The results could mean that heavy smoking overloads the nicotine receptor in human sperm and in the testes, leading to a decline in fertilizing potential. Not only that, the same study claims, smoking men also should be aware that smoking can damage their sperm DNA, passing on faulty DNA to their baby.

To sum up, smokers are likely to have less life-span with less probability to father (or mother) a child. If we bring together all theree studies, the platform for differential reproduction rate to wipe out a genetic variety seems to be in effect. Isn't those enough to stop spreading the genes for smoking? To answer in brief : No, as memes are there to manipulate.

This is where importance of memes comes to picture. Let's take an example of Indian women. They generally don't smoke because in Indian societies, smoking by women is almost prohibited. So, they carry the 'smoking gene' to pass it to the next generation as successfully as other women would have done. The smoking gene doesn't stop spreading because of the meme present in Indian societies to prevent women from smoking. The strong Indian social structure defies the Natural Selection on smokers. In a nature versus nurture debate, in this case, nurture seems to have won - and the habit of smoking will last longer in protective societies. To wipe the habit out, we require the introduction of a new stronger meme to stop smoking itself. The meme is: "Smoking is injurious to health" - and we need a strong awareness campaign.

Reference : Meme and it's activities (my old post)

Darwin, DNA, Evolution, Meme, Genetics, Science

The Bengali Resources at Mukto-Mona

While I write on Richard Dawkins and Evolution in my blog, a group named mukto-mona have taken up their pens to write up in Bengali. It's great to see people scribing for Atheism and Dawkins in Bengali. Let me refer you all to some of the best resources available in Bengali.

1) The first chapter of The God Delusion.
2) A book on Evolution by Bonnya Ahmed - continued for multiple chapters. It is also available as a book at Bangladesh Ekushe Boimela.
3) A Richard Dawkins article on Religion and Evolution.
4) The Journey of Science to find Life - An excellent write up on modern science (especially focussing on the roots of Universe and what is Life) starting from Big Bang to Extraterrestrial life, divided into multiple parts.

The life of Charles Darwin is described in Bengali.

And of course, anybody want to publish their views in Bengali, can send it to them or join a yahoo group called mukto-mona. There are numerous good articles both in English and Bengali published at the site. I bet that anybody will enjoy most of them. To a Bengali living in West Bengal, I would recommend these article since they should know how close they are to someone living accross the border - in Bangladesh.

Atheism, Bangladesh, Bengali, Darwin, Dawkins, Evolution

The Evolution FAQ

I was planning to write about Evolution FAQ for long. It's boring to fight against all apostates of Evolution visiting their own blogs. Rather, if I can prepare a platform at my own blog to fight those, I get a better opportunity pounce on them. By the way, let me first acknowledge that this particular piece is going to be mostly be compiled from various sources in Internet.

The evolution is best described as :
1. is a fact,
2. is also a number of theories,
3. is Science,
4. is also scientific,
5. is naturalistic and purely mechanistic,
6. is falsifiable,
7. is testable,
8. is predictive,
9. has been observed;
9a. in the field
9b. in the laboratory,
10. has occurred in the past,
11. is still occurring,
12. will continue to occur in the future.

Further, we can also note that evolution:

13. is not atheistic (nor Communistic, Marxist, Leninist, Stalinist, etc.),
14. is not evil,
15. is not mandated by law to be taught in US public schools,
16. is not a cosmological theory (i.e., "it don't do origins"),
17. is not a religion nor Religion,
18. is not determined by popular opinion (as can be said of any science),
19. is not a socio-political program or paradigm,
20. is not dependent on the supernatural,
21. does not claim that "Man came from apes",
22. is not progress,
23. has not, will not and cannot be proven (as can be said of any science),
24. Is not random nor relies on 'blind chance',
25. does not violate the second law of thermodynamics,
26. Does not deny (a) God(s), and finally,
27. Falsifying evolution does not prove Creation.

Sounds interesting? Continue reading ... By the way, my pick of the quote would be :

The honest scientist, like the philosopher, will tell you that nothing whatever can be or has been proved with fully 100% certainty, not even that you or I exist, nor anyone except himself, since he might be dreaming the whole thing. Th us there is no sharp line between speculation, hypothesis, theory, principle, and fact, but only a difference along a sliding scale, in the degree of probability of the idea. When we say a thing is a fact, then, we only mean that its probability is an extremely high one: so high that we are not bothered by doubt about it and are ready to act accordingly. The probability that evolution is the correct explanation of life as we know it may approach 99.9999...9% but it will never be 100%.

However I would like to pick up a few more so called technical questions to answer. The pick of the questions are :
1) What is the application of Evolution, or, in other words, can evolution predict anything?

A very good application can be the creation of hybrid species. These species are been created matching the environment they are going to live, so that they can maximize production. This is derived from the fact that nature does select. If everything were created, we would not be able to create new species.
Many predictions made by theory of evolution are proven true. Darwin predicted the existence of 'unit of heredity' that was proved to be gene. And, the genetic similarities the species share among them, are the living evidences of evolution. More recently, the same theory explains the existence of antibiotic-resistant bacteria, who've mutated to resist antibiotic (e.g. penicilin), and 'selected' to become the majority and can resume attacks.

2) If humans are from monkeys then how does monkeys still exist?

Human beings did not evolved from monkeys. They share a common ancestor with monkeys. And a new species generally comes out of the other only if they are geographically isolated. So one can safely assume, that there were at least two groups of apes/hominoids, one evolved to become humans, the other became monkeys.

3) Even if we accept natural selection, what's the proof that it leads to speciation?

I should refer to the speciation events observed in the past in front of modern human eyes.

That's it from my side. I know I could have written a lot more than this, but somehow, I'm satisfied with this. If anybody else suggests me about any common misconception, I am ready to clarify him.
Further reference :
1) FAQ 1 A good technical one.
2) FAQ 2 brief but to the point.

Videos on Evolution

The Discovery channel on Evolution of life on Earth is amazing and entertaining. Here's the list of of the links -
part 1, part 2, part 3, part 4, part 5, part 6, part 7, part 8, part 9, part 10, part 11, part 12. The program is named as "Walking With Monsters". In fact the entire set uploaded by TruthTheory should be watched.

An knowledgable description of the process is found in Dawkins' video -
The evolution of the eye. The full video is available in part 1 and part 2, titled The Blind watchmaker. Another video, comparatively less attractive, was the Nice guys finish first.

The wonderful story of Human evolution is at 5 parts -
part 1, part 2, part 3, part 4 and part 5. The series is named as "Human Life - Evolution To Self-Evolution". It also lists the proofs gathered with respect to human evolution.

Evolution, Science, Dawkins, Darwin.

The Ancestors we had

Of late, I was reading about different findings and theories around Human Ancestors. I tried to summarize what I found out.

Introduction
Over years human beings believed that human beings are special creation of God and got created at His will. The lack of reasoning and strong believe in divine beings forced human beings to rely on divine theories rather than looking at the nature to find out the laws. Over years, human beings have got rid of those burdens through science and started finding the natural laws. Let us visit where exactly we are in terms of knowledge of Human ancestry.

History of Findings
The first light was thrown on this topic by the famous scientist Charles Darwin. In his book named "Origin of Species", he mentioned how a species can separate it out from other through "Natural Selection" and "Evolution". However, he was not able to explain how the first life on the earth was formed. A contemporary scientist, Gregor Mendel came up with the idea of Hybrids which was later converted to study of Gene and DNA. Although Darwin's findings were widely contested by the Church those days, his theories opened floodgates to a new set of discoveries in the medical science and human genetics.

Darwin's theory - A mere theory?
There are a series of accusitions on the Darwin's theory that it was a mere 'hypothesis' and has proved nothing. Most of the accusitions came out of religionalists, who are threatened as this theory annihilates a long standing interpretation that 'God created the Man'. A lot of scientists even today accuse Darwin's theory to be having 'no evidence'.

However, there are yet to be a proof found that goes against the Darwin's theory. The tools used to evaluate the theory were mostly undiscovered at Darwin's time. More and more the human knowledge is growing, the evidences seem to be piling up in favour of it. For example, the use of RadioCarbon Dating to determine the age, use of Genetics to study inheritence, Comparative Anatomy, Geographical distribution or the Fossil records, all supported evolution. On the other hand, there are no counter-evidences of it are found yet, neither a fossil of a human in Jurassic age nor a specific bacteria which defies the laws of natural selection.

The limitation of the study of evolution is the time it takes to perform an experiment to open eyes. Due to less complexity, the evolution can be observed in the level of microbes and it takes less time. However, in bigger creatures, like a human being, it takes thousands of years to become recognizable to a naked eye.

In short, evolution and creation of species take the same position in the world of science as that of gravity. Gravity can not be proved, it can be observed till date, the same is with Evolution. We are yet to know whether gravitation works on all celestial bodies due to our limited knowledge of the Universe, same with evolution of living beings.

Mitochondrial Eve
Coming back to the human ancestors, the study of ancestors are now powered by Genetics and Molecular Biology. The inductive study on human genetics reveals an important fact. A person directly inherits the mitochondrial DNA directly in his/her maternal line. Male sperm contains only enough mitochondria to power the sperm to the surface of the egg – it does not enter the egg. The egg, however, contains mitochondria that have been passed from mother to daughter for countless generations. The only way for mitochondrial DNA to alter is by natural mutations, which occur very slowly when compared with the almost frantic gene mixing we and our parents take part in. Because the rate of mitochondrial genetic mutation is slow, the mutation difference between the two populations can then be compared, and a 'clock' can be produced, enabling the rate of mutation in mitochondria to be established. The genetic survey that produced the whole Mitochondrial Eve scenario didn't just sample Africans and Europeans – it sampled genes from people all over the planet. When mitochondrial DNA was compared, the survey discovered a startling result. Fundamental similarities in mitochondrial DNA in living humans suggested that we all contain genetic material from a single woman who was living in Africa around 200,000 years ago. The woman is called Mitochondrial Eve.

The confusion
Wilson's naming Mitochondrial Eve after Eve of the Genesis creation story has led to some misunderstandings among the general public. A common misconception is that Mitochondrial Eve was the only living human female of her time — she was not. Mitochondrial Eve is the most recent common matrilineal (female-lineage) ancestor for mtDNA of all humans. She didn't live alone – she would have lived within a community. There is no reason to suppose that she had more than one female child. But there is reason to suppose that whatever female children she had, they contained specific advantages for survival over the rest of the population.

Y-Chromosomal Adam
Similar to women, men inherit their Y-Chromosome directly from their father. In human genetics, Y-chromosomal Adam (Y-mrca) is the patrilineal human most recent common ancestor (mrca) from whom all Y chromosomes in living men are descended. Y-chromosomal Adam probably lived between 60,000 and 90,000 years ago, judging from molecular clock and genetic marker studies. While their descendants certainly became close intimates, Y-chromosomal Adam and mitochondrial Eve are separated by at least 30,000 years, or many hundred generations. Y-chromosomal Adam probably lived 65,000 years ago, and mitochondrial Eve some 150,000 years ago. The people living around the same time as these two individuals would have passed on their genes like Adam and Eve, but their Y chromosome and mitochondrial DNA lines would have eventually died out.

Implications
1) It qualifies as an evidence for Single-origin hypothesis. Again, it has nothing to show that human beings started from a single couple, but to show that human beings originated in a single place through mutation.
2) A milestone in the path of Genetic Genealogy.

Future
It opened a door only to the study of Human genetics and evolution. The religionalists are coming up with Intelligent Design theory, which claims to bridge the religion with the Science. It says that the first instance of life was created by God on the earth, after which the evolution took place. It is true that the creation of life itself has been a point of contention as scientists are yet to create a fresh life in the lab. Let us wait till we can see life to be created in front of us and observe all the phase of Human Evolution inside a lab, open in front of our eyes. I will definitely write up on origin of life very soon.

References
1) The Ancestor's Tale by Richard Dawkins
2) BBC article.
3) Wikipedia articles.
4) MSNBC Page on Genealogy.
5) A simple version of the story.
6) An excellent documentory on Human evolution in this site.
7) Articles on Mukto-Mona.