Via VeryShortList: A group of geneticists at Penn State have found that male mice that are made to cohabitate with female mice exhibit “manlier” physiological traits — such as higher testosterone levels and longer periods of fertility — than mice made to fly solo.

The study’s abstract states that the findings “have significant implications for the maintenance of male fertility in wildlife, livestock and human populations.”

Who do ya think is rejoicing in this bit of knowledge more: pregnancy-fixated women or certified lifetime bachelors?