The Genetic Roadblock of Same-Sex Reproduction. For decades, scientists have attempted to produce mammals using only two male or two female parents, but fundamental genetic obstacles made success ...

Try horse racing, where female jockeys regularly jump in the hot seat alongside their male counterparts. But it’s not just the riders facing-off as they thunder down the track.

The Y chromosome is often thought of as defining the male sex. Now scientists find that only two genes on the Y chromosome are needed in mice for them to father offspring.

Try horse racing, where female jockeys regularly jump in the hot seat alongside their male counterparts. But it’s not just the riders facing-off as they thunder down the track.

Try horse racing, where female jockeys regularly jump in the hot seat alongside their male counterparts. But it’s not just the riders facing-off as they thunder down the track.