According to the Defenders of Wildlife, there are around 17,500 species of butterfly found worldwide. Although members of different species have different characteristics, they all contribute to the health and well-being of a wide variety of plants and animals.

Pollination

Butterflies feed on flowering plants. When the butterfly lands on the flower of the plant, some of the plant's pollen sticks to the body of the butterfly. This pollen is then transported to each plant that the butterfly feeds from, pollinating each plant. Because butterflies can fly long distances, the pollen is spread widely, strengthening the plant species.

Food Source

Many animal species depend on butterflies for nutrition. Birds, bats, small mammals, reptiles and other insects all eat butterflies when they can catch them for a meal.

Larval Associations

Some butterfly larvae form mutually beneficial associations with other members of the insect kingdom. For example, some butterfly larvae communicate with ants using chemical signals and vibrations. The ants protect these larvae and are rewarded with the honeydew secretions the larvae create.

Protection

Many species of butterflies are territorial and will chase out any other butterflies that invade their territory. This protects the plants within the butterfly's territory from being eaten by other species of butterfly or their larvae.

Poison Avoidance

Many brightly colored butterflies have absorbed toxins from the plants they have eaten and wear their bright colors as a warning to predators that they are poisonous. After tasting a couple of these brightly colored butterflies and receiving a mouthful of bad-tasting chemicals, the predators learn to associate anything brightly colored with toxicity, protecting the predators from death from ingesting too many chemicals and protecting other brightly-colored animals and insects from being eaten.

More Information:

Defenders Of Wildlife: Butterflies