Butterlflies
Beautify
Mastication and metamorphism make moths
By Callan Bentley
Flat Hat Variety Editor
It is interesting to see which things strike people as beautiful and which strike them as ugly. A colorful mountain sunset is commonly regarded as pretty, while the sight of a tarantula makes many people cringe. Caterpillars are widely thought of us icky little worms, and yet through one of nature's most fascinating and complete transformations, they become the epitome of natural beauty: the butterfly.
Butterflies and their relatives the moths are grouped together in the taxonomic order Lepidoptera. They are easy to observe in nature, providing an alternate focus for the binoculars of some birdwatchers. Their variety, while stunning, is actually much less complex than that of wildflowers. Yet the range of behavior among butterflies and moths is easily comparable to that of birds, and they display all the colors and brilliance of wildflowers. Many people make butterfly-watching their hobby, and even plant special gardens that are designed to attract certain butterfly species.
Butterflies and moths may be differentiated from one another by several methods, none of which is guaranteed to work all the time. All butterflies have antennae with a club-like swelling at the tip. Moths' antennae are straight or feathery-appearing. Some moths have their fore- and hind- wings connected by a small stalk called the frenulum, but no butterflies share this characteristic (with the exception of the males of one Australian species). Nearly all butterflies are diurnal, meaning that they are active only during the day, while a few are crepuscular, meaning that they are active at dawn and dusk. Moths, on the other hand, are generally nocturnal, meaning they are active at night, though there are quite a few that are diurnal, too.
Like other night-flying insects, moths navigate at night using the light of the moon. The reason that moths end up flapping around your porch light on summer nights is that they are mistaking the light bulb for the moon. As the fly along, the "moon" changes position, and the moth tacks to the left or right to compensate for what they perceive as a change in their position, ending up in a long, spiraling flight in towards the light bulb.
Most insects pass through four very different stages in their life cycles, but nowhere is the transition more evident than in the butterflies and moths. They go through four life stages: egg, larvae, pupa, and adult (which then lays more eggs).
The eggs are laid on a particular plant that the species feeds on. Inside the egg, a single, just-fertilized cell divides and differentiates until a small but highly complex larva crawls out. This process usually takes about ten days, though some butterflies overwinter, or sleep through the winter in this stage.
The caterpillar leaves the egg knowing just what he wants out of life: to eat. And eat it does. And eat. It grows exponentially in weight and is at maturity many times larger than it was at hatching.
If you pick up a caterpillar this spring, you will see a wormlike little animal, divided into fourteen segments: a head, three thoracic segments (which bear the six grasping feet), and ten abdominal segments (some of which bear some further "feet," small suction-cup-like appendages). It will have a large number, usually six, of simple eyes on each side of its head. It has a sort of silk-spinning organ on its lower lip, which when it gets big enough, it will use to spin its cocoon, or chrysalis.
Once the chrysalis is spun and the animal is safely inside, it is termed a pupa. The chrysalis is fixed immovably to one spot. It is inside the chrysalis that the process known in children's books as "one of Nature's miracles" takes place. The larva must be turned into an organism adapted for flying, seeing, and procreation. The great digestive tract of the larva must be reduced along with its mandibles. The eyes and brain must be enlarged to cope with the complex visual signals associated with flight. Sex organs are added, as the caterpillar is sexless. Wings must be fashioned as well.
Amazingly enough, most of the larval organs dissolve in a process called histolysis, and the resulting fluid reforms around small versions of adult organs that had grown inside the larva. Some butterflies can complete this complex task in less than ten days, emerging from the chrysalis as a different animal.
Actually, when the butterfly or moth emerges, it is a sorry-looking affair. Wet and rather bedraggled, it must pump up its wings with blood and allow itself to dry out before it can fly.
Around Williamsburg, watch for the white, black-spotted Cabbage White butterfly (Artogeia rapae), the most common species on this continent. Also common in town are several members of the Papillionidae family, which include the swallowtail butterflies, the largest individuals in the Lepidoptera. The Zebra Swallowtail is white with black stripes, while the Tiger Swallowtail is yellow with black stripes, and a black butterfly with deep blue stripes denotes a Spicebush Swallowtail. If you see a medium-sized brown individual with what look like eyes on its wings, chances are you are looking at a Buckeye butterfly. Some kinds of Buckeye are poisonous to eat, some imitate the poisonous ones, and some imitate bees and wasps.
These are but a few of the
butterflies you can see in coming months. There are many decent field guides
available at local libraries and bookstores if you want to learn about other
kinds and get started in the hobby of butterfly-watching.