Humans have them, so do other animals and plants. Now research reveals that bacteria too have internal clocks that align with the 24-hour cycle of life on Earth.
The research answers a long-standing biological question and could have implications for the timing of drug delivery, biotechnology, and how we develop timely solutions for crop protection.
Biological clocks or circadian rhythms are exquisite internal timing mechanisms that are widespread across nature enabling living organisms to cope with the major changes that occur from day to night, even across seasons.
Existing inside cells, these molecular rhythms use external cues such as daylight and temperature to synchronise biological clocks to their environment. It is why we experience the jarring effects of jet lag as our internal clocks are temporarily mismatched before aligning to the new cycle of light and dark at our travel destination.
A growing body of research in the past two decades has demonstrated the importance of these molecular metronomes to essential processes, for example sleep and cognitive functioning in humans, and water regulation and photosynthesis in plants.