From Evans' novel, Life on a Little Known Planet, I found the order of Odonata to be the most interesting and my favorite that he wrote about. Generally, my favorite order is Lepidoptera, but within this book he made them such a bore. Odonata are mysterious insects since they are described as prehistoric insects. Although these insects are more primitive than flies and other true insects, these dragonflies are quite successful. Dragonflies are some of the largest insects, which gives them a predatory size advantage over the other insects (Evans 64). Another advantageous evolutionary trait these specimens have are their eye. Their compound eyes encircle almost their entire head, thus allowing them to see in three hundred sixty degrees. The facets, 28,000 exactly, in the compound eyes allow them to see all directions, and this gives them advantages of being a predator and as prey (Evans 65). As a predator these advanced binocular like eyes allow them to see far away and very good motion movements. However, as being able to see around their entire body suggests that these ancient insects were prey to some creature, and over time these insects evolved and adapted to be the predators. Since their eyes are so well developed, it makes up for their underdeveloped antennae (Evans 65). Furthermore, these creatures have different flying mechanisms than any other insect. Their oblique muscles in their abdomen are directly attached to their wings, thus allowing direct control of the wing beats. Although these insects have muscles attached directly, they are much slower than any other insect with a beat frequency of 30 beats per second (Evans 66). These bugs possess the ability to even fly backwards. What amazes me is the fact that entomologists consider these winged beasts to be primitive to modern insects when these dragonflies are so different, special, and successful. No other insect can do what these bugs can do and still manage to be successful. What else is amazing is even though their wing beat frequency is low compared to that of a bee or a fly, these insects still manage to catch and eat these creatures as prey. Besides just dragonflies evolutionary adaptations, they also have a peculiar method of reproduction. These winged beasts mate together in four steps. First, the male touches his abdomen to make a sperm packet, then he grasps the female by her neck with his claspers, which proceeds her to touch her abdomen to his testes, and finally the male leads the female to a particular spot to lay her eggs (near water) while he guards her (Evans 74). Dragonfly style is weird, but they seem to take mating very seriously and protect their mate to ensure insemination so that their offspring will develop. In addition to the style of mating, these creatures do not just rely on chemical features to determine mates. Since dragonflies have weak antennae, they rely on eye sight to determine mate selection. Color pattern gives a good indication of which mate is the healthiest and has the best genes for their offspring to be successful. Indeed, these evolutionary techniques, although considered primitive, are the ones that impressed me the most out of all the other insects.
Figure 1.
Two adult dragonflies mating. The male above grasps the female by her neck with his abdomen.
I was disappointed in Evans' Lep chapter as well.
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