Were humans meant to be MONOGAMOUS?

i think it depends one the Individuel, some people are very jealous and insecure so they couldn't possibly cope with the idea of somebody being better than them , or being compared to them, it doesn't matter as long as you are all consenting adults and nobody is being cheated on, i suppose we are animals and lots of animals are not monogamous . if they are both happy them that is fine but often it can kill something along the way after a time i have heard