Tammy London, age 12, of Okeene, Oklahoma, for her question:
Why do flowers have scents?
People wear flowery fragrances to attract pleasant reactions. The flowers produce their perfumes mainly to attract insects. Human noses like some scents more than others. Though insects have no noses, each one also has its favorite perfume. Each flower wears the favorite colors and creates the favorite perfume to attract its favorite insect.
In the world of nature, just about everything is done on a give and ¬take basis. Most flowers need visiting insects to pollinate their seeds. Many insects enjoy sweet flowery nectar; some gather pollen and some like to chew tender petals. Different insects see certain colors, but not from afar. Scents travel far and wide on the breezes and insects detect them with their antennas.
In the plant world, perfumery is related to the mating game. The purpose of a blossom is to produce fertile seeds; this depends on merging pollen grains from the anthers with female cells in the stigma. In some plants, the anthers and stigma are on separate blossoms. Others bear both of their flower parts in the same blossom. These can pollinate themselves, but seeds tend to be healthier when pollen comes from another flower.
Friendly breezes may strew pollen from flower to flower. But this is chancy and the flowers can do nothing about it. But they can and do advertise for suitable insect visitors. For example, bees are fond of yellow and blue but cannot see red. Most flowers that depend on pollin¬ating bees wear blues or yellows—and you can be quite sure that all of them produce certain scents that bees find attractive.
Carnations are pollinated by long tongued butterflies. They wear favorite butterfly colors and produce favorite butterfly perfumes. Morn¬ing glories and pale daturas do their best to attract the night flying moths. Magnolias need gnawing insects because their seed cells are deep down in the blossoms. Their scent is designed to attract beetles.
Most, but not all flower fragrances are attractive to human sniffers. For example, in the marshy ditches grows the shy little Jack in the pulpit. Its faint odor is like something rotten. Actually it aims to attract flies and flies, as we know, are attracted to garbage and other decaying material.
Most insects are whiskery midgets. When they visit from flower to flower, grains of dusty pollen brush onto and off their fuzz. In this way, pollen is carried from the anthers of one flower to the stigma of another—and healthy seeds are fertilized.
Some insects can taste foods through their tiny paws. But most of their smelling is done by their sensitive antennas. They can move these feelers to catch the breezes from all directions. In most cases their tiny, though very keen, smelling organs are in the last eight segments of each antenna.