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Insect Wings
By Insecta-Inspecta’s Graphic Art Designer:
Marika Kent
In the last 24 hours,
you’ve probably seen more
than one airborne insect. Most
likely, it didn’t make you
wonder about the physics or
evolution of insect wings and
flight. But if you were to take
a closer look at the basics of
these bugs, you may find that
they’re more complex and
unusual than you thought!
What Are They Made Of?
The wings of all insects involved in propelled flight are
made of a thin membrane. Others, like beetles and grasshoppers,
have thick, hard forewings to give them more passive protection and
lift. They vary in shape, size, and arrangement, depending on the
needs of that insect. Some, like the dragonfly, need broad wings to
lift their thin bodies.
The fragile membrane of the insect
wing is supported by a network of
blood veins in order to give strength to
the wing during flight. Often times,
they’re covered in hair-like or scalelike structures.
How Did They Evolve?
There is more than one explanation on how
insect wings evolved. One theory states that they
developed from the gills of aquatic organisms. As
these organisms evolved into land insects many
adapted to a world of gliding and propelled flight.
At first they were only useful for gliding long
distances, but eventually they developed enough for
controlled flight. It’s estimated that this transition was
completed around 200-350 million years ago. Of course,
this is only one of many theories.
How Do They Work?
Scientist have observed many different kinds of insect
wings- having control over lift, drag, and angles and direction.
They are connected to the thorax by and arrangement of hinges.
Muscles inside the
thorax relax,
depress, and
contract in the
flapping process.
The front edge
of the wings are very
stiff, for easy
maneuverability, while
the rest is light and
flexible. They are thin
so they can curve to
catch air, and flap to
push down against air.
Above are the flight patterns of
three different insects. You can
see the way they curve
downward to push against air,
and cup upward to resist it.
What Else Do They Do?
Tropical Buckeye
(Junonia genoveva)
The color of some insect wings is
essential to its survival. To avoid the eyes of
predators, butterflies and moths use their
wings to camouflage, or blend in, with their
environment. Some beetles have very glossy
wings that their enemies mistake for common
flashes of sunlight. Others, such as the
Monarch butterfly, use bright hues and
patterns to scare off predators, or warn them
of poison.
Insects in the order Orthopetra, such as the
grasshopper and katydid, use their wings to make
sound. Some grasshoppers rub their forewing and
hindleg together to produce sound. This makes the
wing resonate, making a noise that attracts females.
Insect Wings
•involved in propelled flight are made of a thin
membrane, supported by blood veins
•are flexible, so they can curve to control lift and drag,
save the front part for easy maneuverability
•may have evolved from gills on the abdomen of their
ancestors
•have colors or patterns that hide them from or scare
away predators, like the Monarch butterfly (learn more
about Monarch butterflies here)
Bibliography:
“Insect Wings”. Nikon Inc. and Florida Sate University. 28 Jan, 2003
<http://www.microscopyu.com/galleries/phasecontrast/insectwingsmall.html>.
Chew, Peter “Insects Evolution”. 20 August, 2002. 26 February, 2003
<http://www.geocities.com/pchew_brisbane/Evolution.htm>
Damus, Christian. “The Development of Insect Flight”. Hooper Virtual Paleontological Museum. March,
1996. 28 Jan, 2003 <http://parallel.park.org/Canada/Museum/insects/insects.html>.
Dryden, Richard. “Evolution of Flight”. 11 August, 2002. 30 January, 2003
<http://www.nurseminerva.co.uk/adapt/>.
Struttman, Jane M.“Butterflies of North America”. Northern Prairie Wildlife Research Center. 21
February, 2003. 23 February, 2003 <http://www.npwrc.usgs.gov/index.htm>.
Tryler, David J. “Insect Wings - Wonders of Creation”. Biblical Creation Society. 16 Feb, 2002. 28 Jan,
2003 <http://www.biblicalcreation.org.uk/design/bcs002.html>
Thanks to Dr. David Adamski, Department of Systematic Biology, Entomology Section, Smithsonian
Institution, Washington, D.C. for scientific and technical support