At 02:16 PM 3/27/98 +1100, you wrote:
>Would Steve or Shane or anyone comment on whether the one way flow
>counter-current system of oxygen exchange in the avian lung would >be
advantageous cf with mammalian lung structure at depths? My >guess it that
while it is an advantageous at high altitudes to >improve oxygen absorption
it doesn't make much difference at >depths because the air is not flowing
through the lungs.
That would be my guess, too.
>How do mammalian dive depths/times records compare with penguins?
Prosser (1973) lists the dive durations of several mammals:
Bottlenose Whale: 2 hours
Sperm Whale: 1.5 hours
Finback Whale: 30 minutes
Harbour Seal: 15 minutes
Other bird species (Dewar 1924):
Common Loon: 1.2 min
Red-throated Loon: 1.1 min
Black-throated Loon: 0.7 min
Great-crested Grebe: 0.8 min
Slavonian Grebe: 0.7 min
Great Cormorant: 1.2 min
Shag: 0.8 min
Pochard: 0.4 min
Tufted Duck: 0.7 min
Scaup: 0.8 min
Eider Duck: 0.8 min
Common Scoter: 0.8 min
Velvet Scoter: 0.9min
Goldeneye: 0.6 min
Red-breasted Merganser: 0.8 min
Goosander: 0.6 min
Little Auk: 0.5 min
Razorbill: 0.9 min
Guillemot: 1.1 min
References:
Dewar, J.M. (1924). The Bird As A Diver (Witherby, London).
Prosser, C.L. (1973). Comparative Animal Physiology (W.B. Saunders Company,
Philadelphia).
|