Talk about positions! In fact, odonatists (those who study dragonflies) have named dragonflies' mating the "wheel position," after the characteristic shape that is formed by the two mating animals. Females often stay in the uplands and move to the waters only when they are ready to mate," Smith says.ĭragonfly mating is - well, weird but efficient. Males will especially be found there, setting up territories and defending them with vigor. Once they have matured, they can then move back down to the water. "At this point, they are a lot like teenagers, eating everything in sight. They move away from the water, to areas where predators are less numerous and food is readily available. Smith explains that newly emerged dragonflies are not quite mature enough to start breeding, and their exoskeletons have not hardened. Upon emergence, the adult dragonfly must buy some time for several reasons. "Life is short," and the adult dragonfly knows this all too well, for its days are now numbered. The exoskeletons often appear on trees and rocks surrounding the water. After climbing out of the water, the animal prepares for its final molt, an event called emergence. Eventually, it begins to develop adult tissues. Nymphs feed prolifically on mosquito larvae and other aquatic invertebrates.Īt the inception of each growth stage (on average around twelve molts), the nymph sheds its skin, or exoskeleton, so that it can expand in size. However, prey capture is made keenly efficient because of a very unusual bottom lip, which moves out from the head like an upside-down backhoe, scooping up prey and bringing it into the waiting mandibles. Dragonfly nymphs lack wings, so one would think that hunting would be a difficult task. Nymphs exhibit the same ferocious feeding behavior as adults, and the diet consists almost exclusively of living prey. Aside from the aforementioned and the obvious, the rectum also serves as a means of jet propulsion - as water is quickly expelled, the insect is launched like a torpedo, escaping danger when the legs can't move fast enough. So, the nymph practices what is often called rectal respiration - a pleasant thought. Of course, underwater life requires oxygen, which the dragonfly nymph obtains from gills that exist within the rectum. This underwater larval stage can last from one to ten years, depending on the species and climate. Like their water-loving neighbor, the American alligator, dragonflies possess an efficient design that has rendered them timeless.ĭragonflies have an intriguing life cycle, which starts as an egg deposited beneath the water. Since then, there has been little need for change. Concerning structure, it is worth noting that dragonflies are some of the most primitive insects, first appearing in the fossil record 300 million years ago. Damselflies are small and slender compared to the larger dragonflies. Association of Naturalists, explains: "When at rest, damselflies hold their wings together and above their backs, while dragonflies hold their wings horizontally, out to the sides." Smith names size differences, too. What exactly is a dragonfly? How is it different from its cousin, the damselfly? Although dragonflies and damselflies are often called by the same name, differences exist between the fearless dragon and the damsel. Perhaps they go unnoticed to many, but let us take a moment to explore the natural history of these fascinating animals. Certainly they should, for these predators are incredibly efficient, primarily because of their huge eyes and erratic, fighter-pilot flight. What an appropriate name for these ferocious creatures of the dark waters! Smaller insects likely live in constant fear of these tormenting aggressors. What you'll find, of course, are dragonflies. And yes, they are truly magical, much like Puff, flying in a wide variety of "painted wings and giant rings." There you will see that they do indeed exist. but they are real and living in our seemingly tame back yards.ĭo you believe in dragons? If not, perhaps you should take a walk down by the water. Jul/Aug 2006South Carolina's Magic Dragons by Austin Jenkins, photography by Jack Jenkinsįrom the perspective of a smaller insect, these "dragons" attack with biting jaws and catching claws, like creatures ofįantasy.
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