Now, science finally proves that polyandry is beneficial from an evolutionary point of view. Research shows that the reason why sex between two genders has remained the way humans procreate is that females must be given a choice to mate with only the best of the males. One could argue that this could equally be an argument in favour of polygyny. This is not the case. Polygyny does mean that only a selection of males can breed, since there are approximately as many women and men in the world. But it is a patriarchal system that puts the choosing in the hands of the males, which is unnatural and unfavourable, since the “wrong” males are allowed to marry. It also means that the world will be full of sexually deprived males.
Polyandry on the other hand provides all men with a wife. The wife can marry many men, but choose to have children with only one or two of her husbands – the ones that she feels will be the best fathers for her children. Thus, the most suitable males will be allowed to breed but other men will still be allowed a healthy outlet for their sexual and emotional needs.This will also mean that the risk of over population will be contained.
So, the Quran is right in restricting polygyny, while allowing unlimited polyandry.