Sex mom in girl in boy

Description:The imbalance should be greatest in polygamous societies, in which men can father offspring with multiple wives, such as the Kenyan villages. The Trivers-Willard hypothesis states that natural selection favors parental investment in daughters when times are hard and in sons when times are easy. In humans and other mammals, researchers have found that milk composition changes depending on the infant's gender and on whether conditions are good or bad. Well-off parents who can afford to invest in sons should do so because their gamble could give them many grandchildren. In those societies, a son can grow to be a strong, popular male with many wives and children, or he can end up with neither.

Views: 7868 Date: 2019-01-02 Favorited: 35