Feature Animals

Some animals’ internal clocks follow a different drummer

Weird circadian rhythms keep organisms in time with their environments

17-year cicada

TAKING ITS TIME  Circadian clocks in some animals tick-tock to a different beat, like this member of brood II, one of the 17-year cicada species that emerged in 2013.

T. Siegfried

By Tina Hesman Saey

- More than 2 years ago

Circadian clocks, which reset about every 24 hours, are common in organisms living on Earth’s surface.