This theory does NOT come from me and to find it's source you have to search by yourself.
Living organisms adjust it's clock according to external movements.
Human beings living on the Earth has their clock adjusted according to Earth's rotation around it's own axis. Earth rotates also around Sun. Therefore Humans's clocks are dependant first on Earth (Day), then on Sun (Seasons).
Any organism living inside Humans, for example cells or bacteria, are adjusted first to Humans's clock, then Earth's clock and in the end to Sun's clock.
What Human's experience as breath cycle(absorbing and releasing air) can be for a tree a day/night cycle (absorbing and releasing Sun's energy).
Humans form a society. Societies form a nation. Nation forms a civilization. Can you see their's cycles?