Public Radio 89.5 HD1 – Sperm carry half the genes needed for human life. In this hour of Radiolab: some basic questions and profound thoughts about reproduction. To begin, why so many sperm? We turn to the animal kingdom for answers, which lands us on a tour of sperm battles in ducks, flying pig sperm, and promiscuous whippoorwills. Then, we ponder fatherhood, and wonder...in a world where sperm can be frozen and kept for all eternity...what does the future holds for men? And we end quietly, with a widow struggling to keep some essence of her husband alive. Listen Friday at 8:00 to RadioLab on Public Radio 89.5 HD1.