Why do leaves change colour in autumn?

Leaves change colour in autumn due to the breakdown of chlorophyll, the green pigment responsible for photosynthesis. As daylight hours shorten and temperatures drop, plants stop producing chlorophyll. This reveals other pigments, such as carotenoids (yellow and orange) and anthocyanins (red and purple), which were previously masked. The vivid colours of autumn leaves are influenced by factors like species, temperature, and soil moisture. This process is part of the tree’s preparation for winter, as it conserves energy by shedding leaves. The colourful display of autumn foliage is a celebrated natural phenomenon in many parts of the world.