Naked Science Forum

Life Sciences => Plant Sciences, Zoology & Evolution => Topic started by: myriam on 20/05/2010 15:42:29

Title: how do birds manage to breath at very high altitudes ?
Post by: myriam on 20/05/2010 15:42:29

Humans are unable to breath at very high altitudes: climbing Everest requires artificial respiratory instruments.

So how do migratory birds cope?


[MOD EDIT - POST ALTERED FOR CLARITY]

Title: Re: how do birds manage to breath at very high altitudes ?
Post by: norcalclimber on 20/05/2010 17:59:48

http://www.stanford.edu/group/stanfordbirds/text/essays/How_Fast.html

It seems that migrating birds do fly at high altitudes, but most of them seem to be well within the range that humans regularly climb/hike without supplemental oxygen(I myself have climbed/hiked at altitudes up to almost 14k feet).  However there are some birds that fly up to 29k feet(the altitude of Everest) but according to this link the lungs of birds are able to extract much more oxygen than mammal lungs, allowing them to breathe at very high altitudes.

Title: Re: how do birds manage to breath at very high altitudes ?
Post by: Bored chemist on 20/05/2010 19:09:41

"Even humans are anabel to breath at very high altitudes"
you say "even humans" as if there's something special about us.
"climbing the everest mountains requires artificial  respiratory instruments"
No, people can climb Everest without oxygen. It's pretty much the limit of what we can do, but it is possible.

In order to supply enough oxygen to their muscles to power their flight, birds have much more efficient lungs than us.
In the same way that we don't usually need lungs good enough to climb Everest, but we can because there's some spare capacity (to keep us going when our lungs are not working as well as they should) the birds may well have enough "spare" capacity to let them fly over Everest.

Title: Re: how do birds manage to breath at very high altitudes ?
Post by: LeeE on 20/05/2010 23:52:43

Quote from: myriam on 20/05/2010 15:42:29

Even humans are anabel to breath at very high altitudes climbing the everest mountains requires artificial  respiratory instruments

This is not true.  Qomolangma (Mt. Everest) was first climbed without any breathing aids in 1978 by Reinhold Messner and many ascents have been made without breathing aids since then.  However, these ascents, and the following descents, need to be made very quickly and require not only a supremely high degree of fitness and skill on the part of the climber but also intensive high-altitude training so that their bodies become acclimatised to working in low O2 concentrations.