What is the role of daylength in seasonal variation?

The factor of daylight change plays an important role both for all plants and for many animals. Both the ambient temperature and the change of seasons of the year depend on this factor. In plants that are completely directly dependent on solar radiation and the amount of heat, the length of the day determines the periods of the beginning of germination in spring, flowering, ripening of fruits and seeds, dying off in the autumn, the beginning of leaf fall. In animals, the length of daylight hours determines the beginning of the breeding period, molting period, migration to other more favorable territories. The dependence of the behavior and life cycles of living organisms on daylight hours in ecology is called photoperiodism.