Driving Forces of Evolution

What is the driving force of evolution??
What makes one species evolve into another??
Why does evolution occur??
Is it natural selection? or is it perhaps mutation?

The points below are what I understood after a bit of reading and thinking.

Natural Selection drives evolution. Since irrespective of the repertoire of different genes present in the gene pool, if one gene is not chosen above another gene (based on some criteria) then the relative frequencies of genes in gene pool will remain the same and consequently there wouldn't be any evolution.
So clearly some gene has to get selected over another, this selection criteria is called Natural Selection.

However for Natural Selection to work there must be sufficient diversity in the gene pool itself so that some or the other gene is good enough to pass the test proposed by selection. Thus rate of mutation also is a factor at driving evolution. Its observed that viruses mutate at a higher rate and (thus?) evolve at a higher rate too.

However, mutations can either make a gene better at passing the present selection test, or make it worse at it. If they make the gene worse then it will fail the test and disappear into oblivion. But generally mutations don't cause any significant change in the capability of a gene to pass a selection test. These 'neutral' mutations can accumulate to a large number over the span of time. Random drifts in such neutral mutations can result in some gene being replaced by another as result of random event. Might seem a little far fetched, but in the timescales that evolution works under its definitely plausible. And so random drifts in neutral mutations may drive evolution too.

Is there any bias for or against some particular mutation? Is it more likely for an 'A' to convert into 'G' or 'C' rather than a 'T'. Or for that matter any other combination of 'ATGC' in the above sentence. I don't know if such bias is proven, but this bias has been implicated as the reason for the observed GC content variations among closely related prokaryotic species.

Of course all these mechanisms are not mutually exclusive w.r.t gene or time. For different genes different factors would be responsible for evolution. But these forces probably are the reason why one species evolves into another with passage of time.

Adrenalin !!!

Some things in life are so ironic that one wonders what trick is fate playing with them. For example the fact that i have a rear wheel drive VAN !!!!

I guess most people wont understand this....so let me explain. Nowadays i am watching a Japanese cartoon series (with English subtitles) called Initial D which is about a young guy who is an expert drifter but totally oblivious of his skill, the world of cars and that of street racers. The series is about his self discovery and how he turns into the most skilled street drifter.

Things like these appeal a lot to me. The thing that i want most at this point is a good machine under me. When i ride my friends' Honda Unicorn, the raw acceleration gives me a rush i cant describe... once me and Panse had taken a Pulsar 180 for a spin at 12 in the night in the colony and i had touched 105 kmph on the Raagmala road. The Adrenalin kick that i got was so awesome i couldn't sleep till 2 that night. I got the same rush when i first wheelied on my Eterno and then on Belo's Hero Honda CBZ... Theres no feeling like the one you get when an Engine is revving at 7500rpm under your seat and the air is rushing through the small gap between the top of your ears and the head, your eyes watering coz' of the roaring wind!!!! :-)

Well so i want to drift a car now. I really really want to do this infact nowadays i dream myself drifting.... am thinking about how to drift when the lectures go dead, am thinking where and for how much will i get a good rear wheeled drive car in Pune, what modifications it will need. Now the GOD DAMNED irony is that i own a car with just that FR layout....only thing its a VAN.... and with 37 bhp how is it gonna drift??? I am happy that it has enough torque for wheel spins...and it does go to 113 kmph... but it handles really badly.... ofcourse i wouldn't try a drift on that car... but where do i get an FR car in Pune which i can afford??? my budget being 25000 bucks!!!! :-(.... I guess my best bet would be a modified premier padmini or ambassador... thats not happening somehow!!! Why the hell does not India have more FR layouts cars man....it pisses me off sometimes.... and look at the sedans we have...SX4...its a man....damn cars are supposed to be sexy (read female)... i will never buy an SX4 precisely because its masculine... whatever happened to the breed of esteems and balenos....if only they had been rear wheeled driven!!!

Also maybe i should point out that it is possible to drift a FF layout car... but i refuse to drift in a FWD...thats it...

Anyways cars are too costly... and the first thing i am gonna buy with my money is gonna be a bike... something with good performance... no compromises...

May be these are dangerous tendencies... but i am so young i refuse to acknowledge a fact called Death.