If all of the moths had been completely identical, could they have evolved?

i would say no

Explanation:

Depends on the Genes

Explanation:

If all of the moths carry one dominant gene and one recessive gene then it is possible this is due to the fact that if each parent has a recessive gene it can appear a 1/4 chance in their offspring causing a change or evolution of the moths. This idea that recessive genes can sometimes be the key of survival in a species such as snow foxes being white even though white hiar is a recessive trait.