ALT Logo for the 49th New Phytologist Symposium: Biological timing in photosynthetic organisms. An illustration of Earth with the moon on the left and sun on the right. The planet is divided in two between day and night. Plants have been drawn over the landmasses. On the night side, trees in autumn colours grow in North America and a bat pollinating a flower is present in the tropical rainforest of South America. Snowdrops grow across Europe. On the day side, boreal forest extends across northern Asia, grassland occupies southern Asia, the steppe and Australia. Mimosoid plants and large trees are present in Africa. A bee pollinates a magnolia in South-East Asia, and a cherry blossom tree blooms in Japan.