We expect butterflies to be both beautiful and symmetrical; however, some are not. Gynandromorphism is estimated to occur in ...

Scientists suggest female frogs listen for changes in the male calls as a signal for when it's warm enough to mate. Pacific tree frog (Pseudacris regilla) male calling with vocal sac inflated, Conboy ...

When closely related species mate, their offspring sometimes survive but cannot reproduce. This pattern often affects males ...