Humans and most other organisms have internal biological clocks that track the daily cycle of sunrise and sunset. These clocks help time our sleep, metabolism and other essential body functions over ...

When does the circadian clock start ticking? A new study shows that fetal clocks synchronize to the mother in the womb via hormones, highlighting the importance of light and sleep during pregnancy.

The molecular pathway that carries time-of-day signals from the body's internal clock to ultimately guide daily behavior is like a black box, says a researcher. Now, new research is taking a peek ...