Nature Human Behavior • Vol/Iss. . • Nature Human Behavior • • Published In • Pages: 1-10 •
Adult sex ratio (ASR) is negatively correlated with the level of extramarital sex across populations.
Populations with more female-biased sex ratios had greater frequencies of extramarital sex. However, researchers did not find any meaningful effect of ASR on the severity ratings. For a depiction of the severity ratings see figure 3 of the paper.