From the article: “One of the central ideas is that when there is an imbalance in sex ratios, whichever sex is in the majority faces a lot more competition when it comes to finding and retaining romantic partners…men can compete with one another is by being quicker to settle down with one woman, get married and really devote himself more fully to having kids and being a good parent, on the other hand, if he isn’t able to find a partner, he might be inclined to compete in other ways and that’s where you might find increased violence, risk-taking, and competition with other men … When women are more abundant, they are more open to casual sexual relationships, less likely to get married. They are essentially catering to what is often the trait among men, which is to play the field.”