Why Are Flower Petals So Colorful?

A colorful flower is a wonderful, refreshing sight. But flowers aren't colorful just so we can enjoy looking at them--the color is a sign to the animals that use flowers as a source of food. The colors in flowers can even change to send different signals to birds and insects.
Flower petals are colorful because the color attracts birds, bees and other insects. The insects land in the flower and spread pollen, which helps fertilize the flowers and create seeds.
Different pigments produce different petal colors. Anthocyanins produce reds, purples and blues; flavones make pale yellow colors; and carotenes make reds, oranges and bright yellow.
The colors that we see in flower petals aren't actually the colors that insects see! Because insects have different eye structures, they may see totally different hues--for example, a bee may see a white petal where we see a bright red flower.
Some flowers change color as they grow older. This color change is a signal to insects that the flowers are past their prime.
Flower colors have also been assigned meanings by people. For example, red or pink flowers can signify romance, while white flowers are associated with death and funerals. Meanings can change from culture to culture.
University of Vermont--Color in Flowers
Shieldsgardens.com--Flower Pigments

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