මා දුටු පරිණාමය - Part 1

Ever since I was little, I've heard of the "Theory of Evolution". I guess most people today do hear about it. Most (including me) take it for granted. We never really give it much thought. For me, that changed after I had the privilege of reading "The Selfish Gene" by Richard Dawkins.

Most people who know me, would probably have already heard me ranting about how I really enjoyed that book. Do not want to repeat that here, except to say, it is a good read for the inquisitive. I just want to write down a few things that has been bothering me since reading the book. This is more like me trying to coherently write down my own thoughts to make some sense of them, than a guide to "THE" book or to evolution.

Disclaimer:
All the questions I ask below are actual questions that pops in my mind and the answers are how I would "try" to answer if someone actually asked those questions. They are my views and as such can be erroneous at times. I will not repeat this in my answers, please read them keeping this disclaimer in mind.


How Life came to be ?
For life to appear out of nowhere, and to become what it is today, two things are necessary.

• A (not so perfect) replicator
• A finite amount of raw materials which can be used to make replicas of replicators

The word replicator here does not mean a conscious living being. A replicator is anything capable of making copies of it self., be it chemical or mechanical. Simplest example (and the one that's relevant to earth) is a chemical replicator. Say we have a vast pool of randomly moving, various molecules. Assume A and B are molecules which are abundant in this pool. Also assume that molecules of A and B can form a chemical reaction and as a result each can attach with two of the other molecules. So if two A and B molecules happens to meet, they will form a chemical bond to form.

                                                                   A-B

Now if the A side of this new molecule happens to meet another B, that would form a
 
                                                                B-A-B

if this meets another A molecule, that would form

                                                              B-A-B-A

This can go on forever. We will name such a strand of A and B molecules (that itself is a molecule) an Alternating AB Strand. (AABS)

AABS will form individually in many places of the pool, among with thousands of other molecules. But, what's special about AABS is that a given AABS - due to various other chemical reactions - might, at random, break in to two AABS. When that happens, that AABS has replicated it self. This precise replication will cause the number of AABS to grow exponentially, as long as there are enough A and B molecules to go around. This process is neither overseen by anybody, nor are the AABS consciously trying to replicate themselves. It's just another chemical process, which happens when A and B molecules are in the same pool.

Alas, AABS is not the only replicator in our pool. Let us assume another replicator called CDB Strands (CDBS). It is formed by a D molecule bonding with two C molecules and two B molecules on its four sides.
                                                                         C
                                                                          |
                                                                 B -- D -- B
                                                                          |
                                                                         C

Given that there are only a finite amount of B molecules, we see that unconsciously, AABS and CDBS are competing for B molecules. At some point in time we are bound to run out of B molecules to make further AABS or CDBS.

So what happens now? It is likely that this stagnant stage is never reached. This is where the "not so perfect" characteristics of the replicators comes in to save (or create) the world. The replication is a natural process, and being natural, it sometimes makes mistakes. In our case,

• Sometimes, the chains breakup in wrong places. 
• Sometimes, the chains gets attached in wrong places. 
• Sometimes AABS and CDBS attach together and then breakup. 

There are infinite possibilities, even in this most simple hypothesis. These random changes are called mutations. Given enough time we can see these mutations popping up. Some of these mutants might be replicators themselves. Others not. Those who are replicators will spread like the AABS and CDBS, and similar to them start to compete against other replicators for the limited resources available. Again, it is important to realize that these molecules (replicators or not) are not conscious. They do not have a goal to replicate. They do not foresee the future and plan for it. These processes just happen.

Given enough time we can expect some mutated replicators to become better at replication than AABS and CBDS or other replicators in the pool. (actually the correct way to say this is "Some mutations cause better replicators")
 Better how? Well there maybe many ways. Let's just look at a few that comes to mind.

1. Some becomes capable of forming more complex bonds and starts replicating faster
2. Some becomes capable of bonding with other molecules (except A,B,C,D) in the pool and start to spread faster
3. Some others (and these are the most elegant. for no particular reason we'll call them predators) form chemical bonds that are capable of exerting chemical forces on other certain replicators (call them prey), and in the process breaks up the pray molecules (into say individual A,B,C, D molecules) and attach those to themselves. These predators then can spread faster and much more efficiently. 

Note: Though we name them predators and pray, these are still inanimate molecules.

Even more elegantly, some pray will (through mutation) will develop mechanisms which prevents them from being broken by predators. Say, for example an external layer of tightly bound inert molecules. These will then become more numerous. Some pray will then develop capability to break apart these layers of protection and use the resulting molecules for them selves.

It is obvious this can go on and on. And given billions of years, replicators which are unimaginably complex can form. These replicators would then utilize even more extraordinary mechanisims to replicate. Those which can replicate better will grow in numbers while those who are not will fade away. But REMEMBER, still, these replicators themselves are (albeit unseemingly complex) chemically formed molecules. They have no purpose. They are not driven by a goal. These are natural processes, no different from the process of raining or snowing.

The simple hypothesis presented above can be extrapolated to explain how life (I'm not sure whether this is the correct word though) came to be and became what it is today. However, there are still bits and pieces which are not completely clear and if at all, fuzzy, both in the actual theory and more so in my mind. I'm not wise enough to tackle those gaps in the actual theory of evolution, but in the coming posts, I'll try to write about some obvious questions which challenge this theory of how we came to be. I'll end this chapter with a postlude to the above hypothesis, that will hopefully excite your mind, to the extent it has excited mine.


"Remember those replicators we talked about? Where are these replicators today? 


                                  THEY ARE INSIDE OUR BODIES!!!     


The replicators are our GENES. And who are we? We are but a bunch of robots who devote our lives to the survival and replication of these replicators"