Sperm's Solution To Promiscuity

Nature is fighting back in response to female promiscuity by producing a biological 'sperm' chastity belt, say US scientists. Semen becomes more sticky to act as a plug, thereby preventing sperm from competitors impregnating females who sleep around, they found. The Howard Hughes Medical Institute team, along with colleagues from Chicago and Kansas City, studied humans, monkeys and gorillas. The findings appear in Nature Genetics.