Evolution is often thought of as a process that takes millions of years, but that's not always the case. Single-celled organisms, in particular, ride an evolutionary fast track. Within weeks, a ...

The Doomsday Clock, a symbolic timepiece created by scientists 78 years ago, has been set at 89 seconds to midnight. This is the closest humanity has ever come to the metaphorical "end of the world," ...

Nevertheless, the concept of molecular clock has been extremely influential in the field of molecular evolution. One of the most important ideas inspired by the concept of the molecular clock is ...

Subsequent research has shown that Kimura's assumption of a strict molecular clock is too simplistic, because rates of molecular evolution can vary significantly among organisms. However ...