"ToE says that there are two forces in evolution : random mutation , and natural selection ."
"Just a technical point . Evolutionary theory does not require that mutations should be random . Molecular geneticists are well aware that some genes in some organisms mutate more often than others ; alternatively , some genes are conserved more strongly than others . It 's just that hotspots apart , there is no evidence for result-orientated directed mutation of genes . Within certain constraints , they appear to be random , but evolutionary theory as such does n't demand that they should be . Second , natural selection through competition for resources is n't the only force constraining evolution ( though it is the major explanation of adaptation ) . There is also genetic drift which can distribute neutral mutations through populations , and there are probably also other factors such as structural constraints and canalisation affecting which mutations can see the light of day ( i.e . get exposed to natural selection ) and which will not ."
"ToE says that there are two forces in evolution : random mutation , and natural selection ."
"Evolutionary theory does not require that mutations should be random"