Mating is a gymnastic affair for dragonflies and damselflies. The male makes sperm at the tip of his abdomen, but his copulatory structure (penis) is higher up. Before mating, a male curves his tail to transfer sperm to his penis. Most males maintain territories to attract females. An attractive territory contains a good site for laying eggs, such as a patch of vegetation sticking out of the water. Once he has a female, the male clutches her with tong-like appendages at the end of his abdomen. In this "tandem" position the pair flies around until they both flex their bodies to bring the male's penis in contact with the tip of her tail. Once fertilized, the female inserts eggs into vegetation or just drops eggs into the water. The male may stand guard, still clutching her or perching nearby, while she lays the eggs. The eggs hatch into aquatic larvae that takes months or years to mature.

Insects are by far the most diverse and abundant group of organisms on Earth. More than one million insect species have been identified, and estimates of how many species exist range into the tens of millions. Insects got their start way back, in the Paleozoic (about 500 million years ago) and have evolved in tandem with flowers (coevolution). Insects have become specialized on particular flowers, leading to complex sets of adaptations that couple them in a feeding and pollination relationship (a mutualism). Specialization allows for many types of insects to live in the same habitat, accommodating their exceptional biodiversity. In a backyard in the temperate zone, one might find several thousand species of insects. Specialization can occur within one plant species as well, with different insects using different parts of the plant. In just one species of tropical tree, Dr. Terry Erwin of Smithsonian's National Museum of Natural History found about a thousand species of beetles.