Leaves change color in autumn under specific conditions. The autumn leaves are found in crimson, yellow bronze, and many other shades. Much people who live in climates where the seasons change, wait for autumn in order to see the autumn leaves.
The chemical agent present within the leaves of the trees are why leaves change colors. Their presence causes colors of autumn such as the gold yellow of some trees and the scarlet of the leaves of red maple. Some leaves turn to brown at autumn. Some leaves turn yellow and orange. These colors are caused by carotenoids.
The chemical agents that cause leaves to change colors are found in fruits such as bananas, oranges and carrots. They are also found in pink flamingos and animals such as salmon.
Carotenoid are used by trees to absorb blue light energy. The carotenoids also have another function- they help to maintain the stability of chlorophyll, by preventing it from being damaged by light.
Pigments of the anthocyanin family cause the leaves to show colors such as red and purple. The rich color of plum trees, strawberries, cherries and blueberries is also due to the anthocyanin family.
The anthocyanins allow the trees to take back foods from their leaves before they fall. In autumn, whereas the days are hot, the nights are cooler, so more sugars are conserved in the leaves. This makes the tree increase the production of anthocyanins, so more anthocyanins are present in autumn.