A baby mouse made by two mums and no dad

Researchers at the Chinese Academy of science have discovered a baby mouse which has been made with two mums and no dad. It took a substantial feat of genetic engineering to break the rules of reproduction. The scientists said the "bimaternal" (two mammas) animals were healthy and went on to have pups of their own. But there was bad news on the all-male front. Mice with double-dads were attempted, but died within days of being born. The researchers were trying to answer fundamental questions about why we have sex. Mammals, including us, can make babies only through sexual reproduction - aka you need an egg from mum and a sperm from dad. But the rest of the natural world doesn't play by the same rules; some female fish, reptiles, amphibians and birds can go it alone. Welcome to the bizarre world of virgin births known officially as parthenogenesis.