Scientists have discovered that women live longer than men because they are made of different stuff – and the study suggest that sperm may have a detrimental effect on lifespan. Scientists in Japan produced female mice without fathers by using genetic material from two mothers and found that these super females lived an average of 186 days longer than those with a normal mix of parental genes. “The findings, published today in the science journal Human Reproduction, provide the first evidence that sperm genes may have a detrimental effect on lifespan in mammals. And they go a long way to explaining why women have a longer life expectancy than men in almost all cultures. They also lay to rest arguments that physical jobs, more responsibilities and higher stress levels are to blame for cutting years off a man's life.”