In the 1930s, scientists began shipping African clawed frogs around the world for pregnancy testing. What they didn’t know was that the frogs carried a deadly fungal pathogen. That fungus would go on ...

Early in development, many animals pick a team—male or female—based on their genetics, and, with time, acquire the ...

A duplicated gene evolved into a switch that determines sex in frogs, revealing how evolution can safely reshape critical ...