Yes John and others. Birds' breathing is quite different to mammals' but
John Leonard had a sort of idea that it was different but had it the wrong
way around. The following is a very simplified description. Any decent bird
biology textbook will fill in the details. Birds breathe into a system of
air sacs in which inspired air passes directly to the rear of their body,
not into the lungs. Then the air flows ONE WAY out through the lungs through
a selection of air sacs. So there is no wasted space in the lungs of a bird,
unlike the situation in mammals, which have a lung like a one way sack. Air
flows better through an open tube than a sac with one opening. (Of course
there is very complex internal structure as well). A mammal can perform
artificial respiration because relatively little of the air breathed in is
used. A bird's lung has continuous fresh air flowing through it, rather than
the bellows pump part stale air pushed in and out of our lungs. So a bird's
lung is much more efficient and uses more of the inspired oxygen because
there is no "dead space" in their lung. Obviously that is an advantage for
high energy activity like flight, especially at high altitudes. You don't
see birds practising CPR, for good reasons. Unlike us, they don't have
enough oxygen remaining in the air they breathe out for it to do any good.
As for cockatoos flying, off the top of my head, I doubt that was suggested
about co-ordinating wing beats and breathing has anything to do with it.
Birds breathe much faster than we do and cockatoos flap rather slowly. I'd
be surprised if there was any relationship. Besides we breathe using our rib
cage and diaphragm which may effect other muscle activity, birds breathe
quite differently.
It always impresses me that the white cockatoo group have two gears they use
in flapping flight and their switch from one to another flapping style is
quite noticeable. It seems to have a social function. The quick flap method
is often performed in conjunction with tilting from side to side and quick
changes in direction and this seems to be an excitement action from these
birds. This flight is often performed with a lot of calling. I think the
pattern is similar among galahs, corellas and Sulphur-crested, I can't quite
remember it in Pinks.
-----Original Message-----
From: John Leonard <>
To: <>
Date: Monday, 3 May 1999 8:22
Subject: birding-aus Cockatoo flying behaviour
>I was about to reply to John Gamblin's comments about cockatoos' and other
>parrots' call in flight by remarkign that when humans run and are breathing
>deeply, any verbal communication has to be coordinated with the breaths.
But
>then I remembered that birds have quite a different resperatory system
>(isn't it the air goes into the lungs and them is circulated via air-sacs
in
>the bones? can someone give a concise description of this please?), so the
>point probably doesn't apply to birds. It's probabl;y the case with birds
>that, like mammals at rest, they can make vocalisations whih are not
>strictly cooridnated with the inspiration and expiration? like a set of
>bagpipes, they have a good reserve of air!
>
>
>
>
>^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>
>John Leonard (Dr),
>PO Box 243,
>Woden, ACT 2606,
>Australia
>
>'Words had to change their ordinary meaning and to
>take that which was now given to them.'
>Thucydides III 82
>
>
>
>http://www.spirit.net.au/~jleonard
>^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>
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