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True flight was achieved between 250,000,000 to 65,000,000 years ago
by the pterosaurs (Greek for feather winged lizard). While the most
well-known of these flying dinosaurs is the Pterodactyl, the largest
of the pterosaurs was the North American Quetzalcoatlus with a
wingspan of 40 feet from tip to tip . That is as wide as some planes
today.
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True flight in the natural world of today is accomplished only by
insects, birds, and bats. They are the only animals who are able to
propel themselves through the air for a sustained period of time by
flapping their wings.
Insects, the first creatures to develop wings, are the oldest known
true flyers. Their tiny, but powerful, muscles allow most insects to
twist and sway their wings in figure eights, thus enabling them to fly
forward, hover, or even fly backwards.
- Insect Trivia:
A dragonfly flaps its two pairs of wings alternately,
the front ones rising as the rear ones fall. Although bees' wings
seem too small to enable flight, their rapid beats of over
100 times a second allow them to move forward, backward and up and
down. A housefly can somersault in flight to land upside down on a
ceiling.
While insects are considered the most maneuverable of all flying
creatures, birds are considered nature's perfect flying machines.
Every part of a bird is adapted to flying. Their bodies are as
streamlined as an airplane, enabling them to slip easily through the
air. Their bones are strong, yet lightweight, because they contain
many air sacs. The chest muscle, which operates the wings, is
extremely large and powerful. Their wings are covered in tightly
fitting feathers that trap air.
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The feathers have a stiff, straight part running through them called a
shaft. On both sides of the shaft are vanes composed of barbs which
are held together by barbules. The bird's wings, with each of its
feathers, are shaped much like an aircraft's wing--curved on top and
flatter underneath. This allows both wings to achieve lift in the
same way.
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- Bird Trivia:
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Most birds fly at low altitudes below 300 feet and only
a few dozen species fly higher than 3,000 feet.
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A world altitude record of 37,000 feet was set by a Ruppell's vulture
that collided with a commercial aircraft over the Ivory Coast.
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The fastest flying creatures in level flight are ducks and geese,
while the peregrine falcon is found to be the fastest when diving from
great heights.
Of the nearly 4,000 mammal species on earth, bats are the only mammals
capable of powered flight.
- Bat Facts:
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Bats make up one fourth of all mammal species and are
second in diversity only to rodents.
More bats are found in the tropics than any other mammal.
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The large ears and nose leaves of some microbats aid in
echolocation.
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While most humans are unable to hear the ultrasonic beeps of bats,
some children can. Some moths can hear the ultrasonic pulses of bats
and will change their flight path or drop to the ground in order to
evade capture. Others, like the Tiger moth, will click back to
resemble ultrasonic bat calls to confuse bats into thinking they are
another bat.
Bats belong to the animal order chiroptera (Greek for hand-wing).
Their wing structure is very different from that of birds and insects.
A bat's wing is composed of a thin, fleshy membrane stretching from
the elongated bones of the forearm to the bat's legs (and sometimes
tail). The membrane is supported by elongated finger bones; hence,
the name "hand-wing". This wing structure enables bats to move their
wings much like we move our fingers. As they fly they can flip and
turn quickly often using their wings independently of each other.
Like insects, bats are expert acrobatic fliers.
True flight in the natural world is achieved by the presence of wings.
But wings, while making these animals similar, also make them unique.
As hard as he tried, man could not imitate animal flight. It was his
brain that eventually enabled him to fly.
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Last modified: Mon Jul 7 10:48:38 PDT 1997
Copyright © 1997 by Cislunar Aerospace, Inc. All
Rights Reserved.
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