The second theory is similar and is known as "evolutionary neuroandrogenic (ENA) theory of male aggression".   Testosterone and other androgens have evolved to masculinize a brain in order to be competitive even to the point of risking harm to the person and others. By doing so, individuals with masculinized brains as a result of pre-natal and adult life testosterone and androgens enhance their resource acquiring abilities in order to survive, attract and copulate with mates as much as possible.  The masculinization of the brain is not just mediated by testosterone levels at the adult stage, but also testosterone exposure in the womb as a fetus. Higher pre-natal testosterone indicated by a low digit ratio as well as adult testosterone levels increased risk of fouls or aggression among male players in a soccer game.  Studies have also found higher pre-natal testosterone or lower digit ratio to be correlated with higher aggression in males.     
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The understanding of androgen's effects on follicle maturation has in recent years undergone radical changes. While androgens were, for decades, believed to be highly detrimental to follicle maturation and egg quality, recent animal data and CHR's research on DHEA supplementation have radically changed this view. Mouse data developed by investigators at Rochester University School of Medicine (the laboratory is now in an affiliation agreement with CHR), indeed, practically indisputably, established that androgens are absolutely essential to follicle maturation during the very early stages of the process, immediately after follicles are recruited into the maturation process. Between primary follicle and small pre-antral follicle stages, granulosa cells (cells that surround the egg) carry androgen receptors. At those stages, androgens work in synergy with follicle stimulating hormone (FSH), and are absolutely essential to normal development of follicles/eggs, egg number and egg quality.