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4-25-02
Butterflies
Are Favorite Insects for Most People
Most people don't care much for insects. An exception
is the insect that some poets have called a flying flower. Yes, almost
everyone has a soft spot in his or her heart for butterflies.
If any insect group is perceived by humans to be
warm and fuzzy, it is the butterflies. Butterflies really aren't warm,
though. Like all insects, they are cold-blooded. But they are fuzzy! Butterflies,
and their insect cousins the moths, have fuzzy wings.
Butterflies and moths are classified in the same
insect order. The order name, Lepidoptera, reflects the fuzzy nature of
their wings. It means "scale wing." There are roughly 10 times as many
species of moths as butterflies, but most people are more familiar with
the butterflies.
That is partially because butterflies are active
during the day while moths are active at night. In addition, butterflies
are mostly bright-colored. Moths tend to be somewhat drab. Consequently,
people are more likely to notice butterflies than moths.
The color of butterfly wings is achieved in one
of two ways. Some of the color is in pigments, much as it is in most other
animals. In addition, color in some of the brighter butterflies--and a
few other insects--is due to light reflection. In butterflies, small parallel
ridges on the wing scales break up the light into component parts. Water
droplets in the air do the same thing to light when a rainbow is produced.
The color of the beautiful morpho butterflies of
the Amazon is produced in this way. Because the color is the result of
light reflection, the color changes when these butterflies move their
wings. Many morphos are a bright, metallic blue when the wings are held
out from the body. When held vertically, however, the bright color disappears
and the wings appear a brownish gray.
Morpho butterflies tend to slowly open and close
their wings when at rest. Because the color changes as the wings move,
the behavior works to confuse a potential predator, which might be considering
a butterfly meal. The butterfly is playing a now-you-see-me, now-you-don't
game with the predator.
The same effect is achieved by butterflies that
have bright colors on the outside of their wings but duller colors on
the underside. When the wings are folded, such as when the butterfly is
resting, the color pattern may allow the insect to blend into the environment.
Such is the case with the angle-wing butterflies. These butterflies are
medium-sized of a reddish-brown color with black spots. The undersurface
of their wings is gray and brown, colors that imitate bark and dry leaves.
Butterflies are often named after the way their
wings look. Most people would recognize that swallowtail butterflies are
named after the a projection, which looks like the tail of a bird known
as a swallow, found on the hind wings.
The angle-wings have wing margins that are scalloped
and indented as if they had been cut with scissors.
The whites and sulfurs are common butterflies,
with names based on the color of their wings. There is a group of butterflies
called the purples, and, you guessed it--they are purple in color. There
is a banded purple, a spotted purple and a great purple hairstreak.
Peacock butterflies are dusky brown in color but
have eyespots on the wings, similar to those found in the feathers of
peacocks. Another group of brown-colored butterflies is the tortoise shells.
Of course, their wing pattern reminds folks of the shell of a tortoise.
What is it that people like about butterflies?
It might be the bright colors. Maybe it is their delicate nature. It might
be the fact that they visit our gardens. But I suspect that people really
like butterflies because--unlike some other insects--these flying flowers
can't bite or sting!
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