How Plants Tell What Time It Is

The University of Cambridge's Department of Plant Sciences recently conducted a study to find out more about how the internal clock works in plants.

It's fairly well known that humans and animals have an internal clock, or circadian rhythm, that allows us to have a sense of time without looking at a clock. Our bodies make biological changes accordingly. But did you know plants have this 24-hour clock inside as well? The University of Cambridge's Department of Plant Sciences recently conducted a study to find out more about how a plant's internal clock works.

This time-keeping ability is critical to the physical processes of all types of flora, including trees, flowers, and herbs. Examples include moving leaves, emitting scents, and flowering.

During the process of photosynthesis, the plant changes energy received from the sun into a chemical used to function. Sugar is a by-product of that process.

According to lead researcher, Dr. Alex Webb, "Our research shows that sugar levels within a plant play a vital role in synchronizing circadian rhythms with its surrounding environment...Inhibiting photosynthesis, for example, slowed the plants internal clock by between two and three hours."

The study included observing seedlings growing in an area that did not have any carbon dioxide as well as genetically modified plants. Both showed changes in sugar production and internal clock accuracy.