Is man by nature polygamous? If so, then it's unnatural. Because nature doesn't believe in marriages. A penguin's or a flamingo's decision to stick with one mate is entirely exceptional. A man, on the other hand, is a product of society. So the right question should be, is man by society polygamous? Again, the answer is based on exceptions than on rules. In some cultures, it's entirely alright for a man to have more than one wife. Just like some cultures allow polyandry. Depends on the patrilineal or the matrilineal upbringing of the individual in question. After a while, it becomes a matter of convenience. Just like it's convenient for a Kanun-observing Albanian woman to "man up" and look after her family with a gun by her side. It's entirely up to her whether she wants to do that or not. A clear clash of nature versus society. It might be in her nature to be low on courage but the social structures in place might demand her to expose her bravery. The lack of a strong masculine presence in her life compels her to be dutiful. Had the society been in her favour, she would have had more than one husband and thus balanced it out. But that's not happening in her part of the world.