How can the order and complexity we see in nature arise by random chance mutations?
Many people are quick to point out that nearly all mutations are harmful or at least neutral; beneficial mutations are rare indeed. Furthermore, all mutations are random. So how can mutations allow adaptations to come about? The rate (or likelihood) of any given mutation can range from 0.1% to 0.0000001% (Ridley 1993); we can say the average could be 0.0001%. If just one in 100 mutations is beneficial (a generous estimate), that means that the chance of a beneficial mutation arising is 0.000001% — only 1 in 100,000,000! That means that any given beneficial mutation will arise only once per 100,000,000 individuals — while the chance of a given detrimental or neutral mutation will arise once per 1,000,000 individuals. How can this miniscule mutation rate produce adaptations, especially when it’s so much more likely to be harmful or have no effect? The answer comes in two parts. The first, of course, is that the whole system is not completely random; there is selection. The second part
