Why Do Flowers Have Pleasant Smells and Bright Colors?

Although flowers often appear as light and airy symbols of frivolity in poetry and literature, they are in fact designed with an evolutionary purpose that provides the flower with several benefits. These flowers often display bright colors, scents and interesting shapes that cost a great deal of energy to produce. Still, the result is a highly successful design that helps flowers perform their most important function: pollination.

Many garden flowers are equipped with a pleasant scent that can be carried great distances through the air. The scent is usually both relaxing and attractive to humans and, as a result, we have bred them in the thousands and protected them by placing them in controlled environments, such as green houses and gardens where we keep them healthy and safe from pests and harsh weather. Flowers do, however, produce pleasant smells to attract not humans, but pollinating insects. These scents waft across breezes advertising and providing a homing beacon for insects like bees and butterflies.

When an insect is attracted by the sweet smell of flowers, it is often led to a patch of similar or same-species flowers and not to a single plant. With humans, a draw other than scent is needed; for many, that draw is color. Flowers expend a great deal of energy to flower into bright blooms that stand out even amongst others of the same species. The flowers that are healthiest are likely to produce the best color and are also likely to be chosen by browsing insects for pollination. This process helps the healthiest flowers pass on their genes while others die out.

For flowers such as the ghost orchid of Southern Florida, shape is just as important as color. Although many flowers are pollinated by several species of insects, flowers like the ghost orchid form a pollinating relationship with only one insect species. Ghost orchids are pollinated by the sphinx moth, and because of this, they shape their petal system to conform to the long, straw-like proboscis of the sphinx moth. This prevents theft of nectar from other animals and gives the sphinx moth an easy meal. Meanwhile, the stamens are located in just the right area to rub against the moth while it is feeding. Again, pollination is the ultimate goal of the flower.