Monday, December 27, 2010

Human evolution: A simple calculation indicates that human evolution may have been turbo charged.

Earlier today, I happened to be accessing the Human Genome Projects (HGP) website and reading up on a summary of what the Project has learned so far in it's study regarding the human genome.

For those of you unfamiliar with the Project, it's an international scientific research collaboration with the primary aim or goal to successfully generate a complete map or sequencing of all the chemical base pairs which make up DNA and to identify and map the approximately 20,000–25,000 genes of the human genome from both a physical and functional standpoint. In 2003, the Project released a complete sequence "map" of the human genome.

Amongst the summary of their results, is the following very interesting statistic:

[The human genome contains 3164.7 million chemical nucleotide bases (A, C, T, and G).]

Simply put, the human genome consists of all the chromosomes which in turn are made up of DNA. Now DNA can be likened to a ladder where each "rung" is made up of 2 of these nucleotide bases connected together ... known as a "base pair".
So according to the HGP statistic mentioned above, therefore the entire human genome consists of just over 3 billion of these base pairs. Picture this as an incredibly long ladder with over 3 billion individual rungs. Thats an incredible amount of stored information but essential to create a human.
It's important that you understand that each one of those "rungs" had to be created randomly by nature and is the basis of evolution ... initially simple structures becoming more complex over time and becoming incorporated into the organisms genetic structure. This process can also be referred to as genetic mutation.

Now that figure of 3 billion rang a bell.

We're told that the age of the Earth is approximately 4.5 billion years and furthermore, that the 1st evidence of life (simple cells) dates back to approximately 3.8 billion years. So we can see that life appeared not to long after the creation of the Earth !.

I've always assumed that genetic mutations tended to occur relatively slowly and accumulated over long periods of time through a process of natural selection ... but here's the hard to believe part ... at least for me.

We have a total of approximately 3.164 billion nucleotide base pairs.
We have a period of approximately 3.8 billion years since the dawn of life.

So, a simple bit of maths shows that to get from that original extremely simple cell to a human, means that random evolution coupled with natural selection pressures had to SUCCESSFULLY add a completely new rung to the ladder on average almost EVERY SINGLE YEAR !!

Now that wouldn't be so hard to comprehend, but we now have to factor in the understanding that the majority of random mutations are at best, non-lethal to the host organism, and at worst, deadly to the host organism. Adding new rungs to a ladder is a completely random event and no guarantee that it will benefit the host organism.
So we can assume that to compensate for the vast majority of non-viable rungs, that we need an evolutionary rate that far exceeds one rung every year and most likely would have to increase that rate of rung addition to perhaps 2, 3 or even more rungs added per year to ensure at least one non-lethal rung being added and the organism successfully evolving through mutation. Even if the added rung was non-lethal, nature would still have to compensate for potential losses of the organism, and therefore the newly added rung, through early death before it could breed and pass on the newly acquired mutation.

Now, this may just be me misinterpreting how evolution actually did manage to get from that single primitive cell to us humans ... but simple maths seems to imply that something highly unusual had to have occurred to keep the number of viable and non-lethal rungs being continuously added at a rate sufficient to reach the current number of just over 3 billion.

Now I have to state quite clearly that I'm not a believer in Creationalism but after having done the above simple calculations, I have to now say that I can't really credit our current understanding of how evolution and mutations work as being the complete and simple answer either. I'm beginning to believe that we're missing some vital and key component in our understanding of how evolution REALLY works.

,,,,Now that article does have me pondering.

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