Possessiveness

"So it's strange that even though fewer males are born, the population of boys keeps increasing, right? That's because when a male gets pregnant and gives birth, it is mostly boys, and the pregnancy period for males is about five months—half of the roughly ten months for females. If a female also becomes pregnant during that time and gives birth to a boy, the ratio of males naturally rises further. You might still think it's strange that males keep increasing, but this is where people with multiple partners come into play. The birth rate with just one partner is low, but those who have other partners also have children with them, and those children are mostly boys. You see where this is going, right? Unfortunately, in your circle and this city, polygamous families are rare, but in my village where I was born, they were quite common."