A belief? What does the evidence support? Where is your evidence for supernatural creation? Evolution relies on variations in the way that genes are expressed. Those that give the owners advantages in reproduction success are those that have advantages in passing their genes to future generations. In a single generation, these effects may be small but over long periods of time, the cumulated effects are substantial. The disadvantage of this process is that the majority of these variations are detrimental to the owner which results in a lower reproduction success; these variations consequently die out over time. Examples of disadvantaged variations are those that result in inherited diseases.
