Blogs on Scientific Philosophy

A few interesting posts I have come across over wordpress thanks to wordpress tag surfer. The first one discusses how the knowledge was developed in ancient civilizations and wherefrom it started to go dark. The blogger discussed about early socirty, mythology-religion development, trade and economy and also how the religion evolved. He did not forget to mention a few wise men of ancient greece (his writing is Europe oriented).

The next one tries to explain the relationship between stress and development. The blogger diagramatically described how the fear is related to stress-development gap. And he also examplified in support of his hypotheses, with modern day issues and reactions.

The last one talks about the critical thinking - to explain how we accumulate knowledge. I have pointed out the similarity of his writing with Dawkins' letter that I have already discussed and translated too.

Happy blogging, keep it up.

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

To Change the Species - Just Change the Genome!!

The news appeared in most of the leading newspapers that scientists have successfully transplanted the entire genome of one species of bacteria to another. This is carried out by the institute lead by J. Craig Ventor, a prominent participant in the human genome sequencing.

The researchers worked with Mycoplasma mycoides (a microbe that infects goats) because it has one of the smallest genetic blueprints of any known self-replicating organism and lacks cell walls, making it easier to insert new DNA. They isolated its entire genetic code - one chromosome that forms a circle-stripping it of all its proteins, and then added genes to make a host organism blue (to make it easy to pick out in a Petri dish) as well as resistant to the antibiotic tetracycline. The scientists added close relative Mycoplasma capricolum (another goat pathogen) to a solution containing M. mycoides' genetic material and gently mixed it for a minute. After three hours of incubation, the resulting microbes were exposed to the antibiotic tetracycline.

The Evolution and Natural Selection are played once more in the labs as the variants having favorable mutations (artificially imposed) survived and the rest perished. After three days, large colonies of blue, antibiotic-resistant microbes had formed. Roughly one in 150,000 of the M. capricolum microbes had absorbed the new DNA and transferred it to daughter cells. The daughter cells displayed no trace of their original DNA while taking on the entire form and function of the original bacterium.

The ultimate goal is to make cells that might take carbon dioxide out of the atmosphere and produce methane, used as a feedstock for other fuels. Such an achievement might reduce dependency on fossil fuels and strike a blow at global warming.

Scientists remain unable to create synthetic life in the lab. "If we're trying to understand the origins of life and cellular life, it would be ideal to have all the chemical components in a soup to spontaneously go together and form a cell", Venter says, "We're a long way from that."

References :
1. Sciam
2. NYT

DNA, Evolution, Genetics, Origin of Life, Science

Pushing the Limits of Speciesism

I heard about a lot of hybrids, but never of one involving humans, except in fiction stories. Now, those stories are becoming truth, may be sooner than I expected. Britain has dismissed the plan to outlaw an effort to create a human-animal embryo. Under the new guidelines, Scientists are allowed to create three different kinds of embryos. The Gurdian notes :

"The first kind of hybrid allowed under the bill, known as a chimeric embryo, is made by injecting cells from an animal into a human embryo. The second, known as a human transgenic embryo, involves injecting animal DNA into a human embryo. The third, known as a cytoplasmic hybrid, is created by transferring the nuclei of human cells, such as skin cells, into animal eggs from which almost all the genetic material has been removed."

The scientists will be allowed to grow such an embryo for only two weeks - to develop new treatments for incurable diseases such as Parkinson's and Alzheimer's. It also restricts the creation of "true hybrid" embryos, which would involve fertilizing a human egg with animal sperm or vice versa. It would also be illegal to put them inside human womb (don't know about the animal one). This kind of embryos would be the major source in the stem cell research.

The moral brigade is already started shouting against it. I got a few letters on the internet those describe it as 'Frankenstein science'. However, they might not know that Chinese have already created such an embryo for a similar purpose. Other experiments are proceeding quietly in research facilities around the world. At the Mayo Clinic, scientists created pigs with human blood. Stanford University in California is considering attempting to create mice with 'human' brains.

The new regulations came as a U turn over Britain's last decision to outlaw it. Many scientists like Dawkins put huge efforts behind it - to set morality free from religion. Dawkins said once that a human embryo is 'biologically nothing different from an Amoeba', yet we shout against its use in stem cell research as it is 'would-be-human'.

However these researches will definitely push to revisit our ancient way to describe a 'human-centric' morality. As Darwinian Evolution said and Genetics later verified, we are very closely related cousins. These experiments are taking that view a bit further. A rat with a human brain might possibly be able to suffer similar emotional pain to that of a human being. So, a 'human-centric' morality can be called an example of 'speciesism'. In this video, Dawkins talks in favor of animal rights and against speciesism.

"Today we live in a specisist world. We are automatically, without thinking, without question assume that there's one law for Homo sapiens and one law for the rest of the animal kingdom. That is speciesism. Now of course, if you object the speciesism, you are in a sense letting yourself wide open to reductio ad absurdum when people will ask - where will you stop? Should you care for cabbages because there is an evolutionary continuum between us and cabbages if you go sufficiently back? You'd be starved to death, if you are that insistent upon rejecting specisism. My answer to that is that we should not be any kind of '-ist' of that kind. We have rather a continuum as a sliding scale from Gorillas and Chimpanzees being very close to us and cabbages being very long way away. And there is no way why we should erect a wall at any particular fence. There are some animals who suffer, can think, can reason, can suffer emotions which deserve and must have a greater moral consideration from us than other animal."

He continued to make a case for other animals to be treated with minimal morality or to stretch the morality of our perception:

"What I am saying is that it's a matter of a merest accident that the intermediates happened to be extinct. That's the only thing that enables us to erect this great fence around Homo sapiens to say that there are humans in one side and the whole of the rest of the animal kingdom on the other side. It's very hard to make a purely scientific case for conserving any particular species. ... The only case I can make is the emotional case, and what's wrong with that? We are emotional beings. I feel emotional about it. I want to save gorillas, to save rhinos; I want to save these magnificent creatures which are built up over millions of years of evolution before they go forever. It's an irrevocable thing and that is an emotional argument."

I wonder what position the religious people would take on this since it cannot be called a 'human'. Will it have a soul? I'm pretty sure that liberalist and extremist religious people will fight once more. Let's wait and find out what their stance would be.

Reference : Dawkins write up on Speciesism. The list of books on speciesism at Amazon.

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.

Towards a science-aware society

Of late I have been writing on the ill-effect of religion to resist the science and the scientific study of nature. After writing on the Memetics of the religions, I decided to look further deep to understand why exactly science is obstructed – is the religion the root cause or human nature itself blocks the development. I discovered that the intuitiveness, a virtue of a human being, is considered to be the worst enemy of science education. In other words, human beings are programmed to oppose science instinctively. The best explanation comes in favor of it by analyzing the natural learning process of a human being.

Prior to exposure to organized study of science, children use their intuition to judge and gather knowledge about the world they see – both physical and social knowledge. The examples social knowledge can include the identification of parents and close relatives. The physical domain experiences include the observational fact that objects fall in the ground or it hurts more if dropped from higher places.

The problem with teaching children the science is not what student is lacks, but what the student has already assumed to be the truth as per physical domain experience. As an example, once a child ‘knows’ that objects fall, it’s difficult to convince him that the Earth is spherical in shape, because they perceive that people should ‘fall’ out of the bottom half of the sphere. Also, a flat world fits their observation that they can see, sometimes, in a dilemma, they pick up a false idea of a flat livable flat place on top of a spherical Earth.

Michael McCloskey, a professor of Cognitive Science in John Hopkins University, conducted a survey among adult American students to find out how scientific they are. He took the domain of objects in motion, something that people both read theories and observe a lot of times in their day to day life. He presented diagrams to depict a physical condition and asked the students how the motion of the object would be in those conditions. He asked how a ball should continue after coming out of curved tube, what trajectory a ball should fall when dropped from a moving aero plane or from the roof and many more of these. The result was strikingly different from what was expected, people went by ‘common perception’ or what we see in life. Most of them told that the ball from the aero plane will fall straight, or come out of a curved tube in a curved motion. Interestingly, when asked about the motion of water out of a curved hose-pipe, they mentioned it to be straight, since it comes into their direct space of observation.

McCloskey concluded that everyone (children or adults) builds a naïve theory in their brain out of the observations they make. These theories are often wrong and also carry casual explanations along with them. These naive theories are dominant in ancient scripts and continue to be the base of pseudo-science. A sustainable knowledge of science needs to overcome these barriers of naïve theories within a human being.

To overcome this resistance, the establishment of trustworthy source is necessary. Children, when unable to verify most of the claims, try to verify the sources of the claim. To a child, parents and the closer relatives are the most trustworthy source. So, in case science teacher in school teaches them about evolution and parents back home opposes that, then, they are bound to take the parents’ one. Not only that, they grow idea about books and newspaper those are trustworthy. They tend to believe ideas from an adult who is confident and who can map their theories to real life. Most notable point here is the trustworthiness they gather, carries to their adulthood. And it holds true for religious, political and moral beliefs also. The idea to overcome science resistance is to inject science at every level of information source, so that people understand them as trustworthy, even if it conflicts the naïve theories in mind.

In India, the presence of naïve theories in the form of superstitions is very potent. One example I can pick up, is related to “Snakes eating milk and banana”. These theories are present from religious background and get verified by the children from their trustworthy adults. I used to believe that snakes really eat them as society elders talked about them. I came to the correct knowledge only after a science campaign run on television. The naïve theories (example: firm land should be kept idle for a certain period of time to retain land-fertility) present among farmers are also the result of their intuitions, and campaigners find them difficult to replace with modern science (following crop-rotation).

The discussion above points out that we need more prominent scientists to come up at the stage, at public debates or at television programs to articulate and defend science as a unique process of acquiring knowledge. The society today, if it is superstitious and religious like that of India, is a result of egoistic apathy of the scientists, who ignore their social responsibility to convey their message to common people. More research and more innovations might bring more money to them, but ultimately, in a democracy, people rules. So, a social awareness of the science is the only way people can become scientific, or at least can consider science as a trustworthy source of information.

Science, Cognitive Science, Atheism, Evolution, Society, India

Memetics and Cultural Evolution: The Roots of the Religion

What is Memetics?
The term "meme" coined and popularized by the biologist Richard Dawkins in his book The Selfish Gene, refers to a "unit of cultural information" (cognitive or behavioral pattern) which can propagate from one mind to another in a manner analogous to genes (i.e., the units of genetic information). Some contemporary examples of meme can be popular proverbs (“Hard work pays”), gossips, health consciousness (“wash hands before eating”), nursery rhymes (even epics and religious books), conspiracy theories, terms and phrases (“Whassup”) and a lot more.

Memeplexe or Meme-complex is a group of Memes; those are interdependent and survive as a ‘colony’ of memes – such as religion, culture or political doctrines.

Memetics, coined as a similar sounding word of Genetics, is an approach to evolutionary models of information transfer based on the concept of the meme. The popular Memetics hypotheses that memes do not replicate only, but refined, recombined or modified in new memes.

Propagation of Memes
The better a meme can be copied; more it will become common part of the culture. This depends on copying fidelity (accuracy of copy), fecundity (rate of copying) and longevity of the meme. The successful propagation of memes depends on various things – experience of the individual, speculation of the individual, social censorship, distinction of source of the meme. Two communities, those who mix rarely, can be thought of as memetically isolated communities, e.g. Americans and Arabs.

Children as the media of meme propagation
As per behavioral evolution, children who are more obedient to their parents get natural selective advantage over others. This unique nature of children enables human civilization to build upon past experiences. Children, who accept the words of adults as rule of thumb, as “Don’t go to cliff of the roof”, “Don’t swim into the deep water” or “Don’t go to the forest alone”, are more likely to survive and reproduce later. When grown up, they propagate their memes, accumulated in the childhood to the next generation, and may be in a modified format. The memes that are more appealing tends to propagate more accurately than the others.

Religion as a Memeplex
Religion and the existence of God as a set of memes have got the unique appeal to human civilization. It provides plausible answers to deep and troubling questions of the nature, suggests the ‘injustice’ will be rectified in the next and one will be placed in relatively good or bad places after death depending on the performance in this life. Dawkins, in his book The God Delusion (pg 199) has provided a list of religious memes those had high survival values in human civilization.

The reasons for the high survival of religious memes include social experience, speculations and distinct source. The religious people always express their experience as positive to add the survival value to the meme, e.g. faith is a virtue and prayer is the way to seek help from God. People speculate about mysteries of nature, miracles, life and death that ensure high survival for the religious explanations. Last but not the least, the revered and distinct source (religious leader/book) adds additional survival value to it. Presence of ‘exclusivist’ memes in the organized religion is striking. For example, punishment or ostracism for heretics, apostates and blasphemers are such ‘exclusivist’ memes. These memes protects the memeplex to get infected from 'outsider memes'. One of the distinct features of Indian culture is the lack of 'exclusivist' meme, that enables India to be built on top of a unique plural society.

A reflection on the above theories can provide you clues why religious sects exist. Sects came into being due to different variation of ‘interpretation’, resulted out of different memetic evolutionary path followed by different sects. Same way, the recombination of different memes resulted in same religion to be performed in different ways in different regions.

The Roots of Religion
As we know how religion and the features propagate, we can proceed how it came into being initially. The best explanation, although controversial, I have got is from Daniel Dennett, in his book The Intentional Stance. He classified the stance of human beings with respect to an object in three ways – physical stance, design stance and intentional stance. In a Physical stance, man tries to explain the object and its’ behavior in terms of natural laws. The second one is design stance, to predict the behavior of the object as it is designed to perform that, e.g., the bird flies by flapping the wings or an alarm clock is designed to ring at a particular time. This is in effect a shortcut over the earlier one and provides advantages if established upon experience. The last one is the intentional stance, that enables personification of the object and predict the behavior as per the intention of the object. The intentional stance, very frequently gave humans advantage over other animals e.g., to identify predators (like Tiger) and cattle (Dogs). The noticable point is that the abstraction of objects is increasing in each stance. The human civilization is basically a race from the third one to the first - initially they had to take the more abstract ones due to lack of knowledge to go to physical stance. Dennett argues that it is best to understand human beliefs and desires at the level of the intentional stance, without making any specific commitments to any deeper reality to the artifacts of each and every folk psychology. The gods and the God, along with the Angels and Daemons are nothing but these personifications of these objects - survived in human societies as memes.

The Future
The clash of reason and religion is basically the clash of memes. The memes of reason are supported by evidences, those a human being can directly experience. The memes of religion are appealing and has high propagation value. The battle is likely to continue in future.

Conclusion
A memetic view of religion is undoubtedly better than any view proposed by the popular religions as the ‘first cause’ or the beginning of themselves. The explanation gives us idea on how the simple ‘personification’ of unknown objects turned into what we see as organized religion, by means of propagation of memes. The hypothesis, may have a lot of technical drawbacks, but overall is very effective in this case.

References
A bibiliography on meme.
The multi-dimensional evolution.
Susan Blackmore and her "The Meme Machine".
The Selfish Meme - a concept.
Intentional Stance made easy.


Atheism, Evolution, Meme, Dawkins, Religion.

The Origin of Life : RNA Hypothesis

Of late I have been reading books by great scientists. The best one as I found out, is one from James Watson, named as DNA : The secret of Life. I have gone through first three chapters of the book only. It has given me a lot of knowledge on how the life has been evolved on the earth.

The basic mystery that I had prior to reading the book was on the relation between protein and life. The explanation tha I got is really interesting. It's the DNA that replicates a part of it (transcribes) to messenger RNA. The messenger RNA then comes to Ribosome and gets translated to amino acids with the help of transfer RNAs present there. Amino acids are catalyzed by RNAs to build polypeptide bonds among them to generate Protein. But, DNA, RNA and the Proteins are built on nucleotides.

Here the RNA World hypothesis comes into picture. It's now obvious that RNA has a property to store, transmit and duplicate the genetic information as DNA. It can also produce proteins - the building block of life. According to this hypothesis, RNA was independent initially and later evolved a barrier outside to form later form of life - like bacteria and Amoeba. Carl Zimmer, who's working on this for long, believes that RNA Viruses are the last common ancestors of life. They evolved into DNA based viruses and since then, the superior system of DNA based life exists.

The most interesting part to me was the role of Natural Selection in the process of forming RNAs. Initially nucleotides (purely chemical substance) were free floating. They were often formed bonds to bind together. but certain sequence of bonds had properties to bind and go to more stable state. As each chain grew longer it attracted more matching nucleotides faster. RNA is one of these giant nucleotide chains. In an RNA world, different forms of RNA compete with each other for free nucleotides and are subject to natural selection. The most efficient molecules of RNA, the ones able to efficiently catalyze their own reproduction, survived and evolved, forming modern RNA. The competition grew and resulted in co-operation between separate RNA chains to produce more and more different proteins. DNA came later and so lipids, carbohydrates and other materials since a collaboration of such materials were more 'sustainable' and 'replicable'.

The main problem of this thesis was the instability of RNA while being exposed to UV Rays. Recent experiments also suggest that the original estimates of the size of an RNA molecule capable of self-replication were most probably vast underestimated, the size can be smaller than one have thought of. More-modern forms of the RNA World theory propose that a simpler molecule was capable of self-replication (that other "World" then evolved over time to produce the RNA World). There are many more hypothesis surrounding this RNA and life but the lack of undisturbed sedimentary rock from that early in Earth's history leaves few opportunities to test any of these hypothesis robustly.

The idea of RNA world was first proposed in Carl Woese's The Genetic Code. The term was coined in 1986, by Walter Gilbert.

The origin of life on earth is a mystery that Humankind ought to solve. The proper understanding might give us several advantages over the natural world. We may create our own microbes to fight against the diseases caused by virus and bacteria. We will have much better understanding of each of the building blocks of our own body.

News Reference from BBC :
Creation of Viral life by researchers.

DNA, RNA, Evolution, Origin of Life

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.