The Destabilization of Evolution

If for a species, survival is to remain in the same form, evolution does not happen to increase chances of survival because it actually decreases it, as the more evolved a species is the less likely it is to survive. Evolution happens when something is born with an unlikely change that is likely to die again, but yet finds an unlikely way to survive anyway. However, the only way it can deal with the problem is with the same thing that caused it, through further change, and as most change is deadly, it only becomes less viable the more it evolves, but it may still survive for a while if it is viable enough. Evolution is not the survival of the fittest but the survival of the fittest freaks of nature, though the freaks of nature themselves may be quite unfit.