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Author Topic: Why are bats so silent in their wing flapping ?  (Read 15799 times)

Offline neilep

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Why are bats so silent in their wing flapping ?
« on: 27/12/2007 15:37:55 »
Dearest wingologists,

see this bat ?



In the summer.....when these bats are flitting about I can't hear them at all....
....does this apply to ALL bats ?...even the big fruit eating ones ?.....but if not...then how does this little bat fly so that I can't hear it at all ?

Thanks

Neil

xxxx






 

Offline Karen W.

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Why are bats so silent in their wing flapping ?
« Reply #1 on: 28/12/2007 01:59:04 »
This is how they fly but It doesn't say why they are so quiet, but I assume after watching them that they flap to gain momentum and thrust and then glide and swoop more then flapping! LOL!
http://www.tlgrant.r9esd.k12.or.us/english1/vonlubke/bats/batstext.html

HOW DO BATS FLY?

Bats fly by flapping their wings. The wings are moved by strong muscles in the back, chest, and shoulders. During the wing stroke, the part of the wing between the body and the fifth finger pushes downward against the air, providing lift. Lift is the force that keeps the bat aloft. The part of the wing between the second and the fifth fingers pushes backward against the air, providing thrust. Thrust is what keeps the bat moving forward
 

Offline Karen W.

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Why are bats so silent in their wing flapping ?
« Reply #2 on: 31/12/2007 01:10:10 »
Hear is another site which has a lot of description about how the wings are built but no where can I find anything about why they can fly so quietly!Perhaps it is because they have joints in their wings??? Cold be that their bones are so light and blood circulation through the wing.. they can hover and also flap there wings to take off some swoop down which may mean less audible flapping as they glide past.. I really am not sure!

http://www.tohonochulpark.org/PDF/Bats-FlyingAcesOutreach.pdf

Flight
Bat’s wings are actually modified arms — large upper arm bones connected to shoulders
and long forearms with fingers that have stretched to form the foundation of
the wing. Some wings are long and narrow for speed, others are shorter and broader
for greater maneuverability when hovering to feed. All bats have a thumb, which
appears at the leading edge of the wing. Most bats have a variable-sized claw on
this thumb which is used for climbing, handling food, and fighting. The other fingers
of the “hand” support the wing itself. A membrane of two thin layers of skin covers
the fingers and forearms. It contains blood vessels, visible when the wing is stretched
open, and muscles that control the curvature of the wing in flight. Special valves in
the blood vessels allow the bat to control the supply of blood circulating in its wings.
This helps the animal to cool down after flying all night. Remarkably strong and
resilient, the wing membrane, about as thin as a rubber glove, heals quickly if torn or
damaged. This wing membrane extends along the side of the body from the shoulder
to the shorter hindlegs and feet. In some bat species the membrane partially or
completely covers the area between the hindlegs, called the interfemoral membrane
or uropatagium. It is supported by the calcar, a bony ankle spur. This membrane may
also enclose the bat’s tail, but some species have no membrane at all, and some
have no tail. The interfemoral membrane is used to help catch insects just like a
butterfly net.
Bats legs are short and their knees bend backwards or to the side; their toes curl
forward rather than back. These adaptations help the bat to maneuver when they
are not flying and when they roost upside down. Why do bats hang upside down?
Flying animals must be as lightweight as possible and bats have evolved various
ways to limit their weight such as wings that are covered with skin membranes and
tiny leg bones that are incapable of supporting the bat’s weight in an upright position.
Hanging upside down, the body weight is suspended, enabling the fragile bones
to support more weight. Some bats begin flapping their wings while still hanging
from their perch to get a lift into the air, other bats need to “fall” into flight, picking
up speed and using less energy to get itself airborne. A few species can actually
take off from the ground.
 

Offline Karen W.

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Why are bats so silent in their wing flapping ?
« Reply #3 on: 31/12/2007 01:11:25 »
OH their wings are also very thin and are self repairing when they get torn... Isn't that cool! LOL..Sorry off subject!
 

Offline opus

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Why are bats so silent in their wing flapping ?
« Reply #4 on: 02/01/2008 19:52:35 »
This is also slightly off subject, but I have read that they urinate when roosting upside down-      eeeeeuuuuuwwww!
 

Offline i am bored

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Why are bats so silent in their wing flapping ?
« Reply #5 on: 05/01/2008 23:45:01 »
thats nice
 

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Why are bats so silent in their wing flapping ?
« Reply #5 on: 05/01/2008 23:45:01 »

 

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