At 07:28 PM 3/31/98 +0900, Desmond Allen wrote:
>>Interesting! This suggests that this type of metabolic depression may also
>>combine with respiration in limiting the duration of a dive.
>
>More likely perhaps that the central nervous system itself maintains normal
>working temperature via some kind of counter current heat exchange system -
>like in gull legs, or the sinuses(?) of large savannah mammals. Perhaps
>penguin muscles work effectively at low temperatures, allowing them to
>feed, and to escape predators at low energy cost.
Hi Desmond,
We had established in earlier discussions that most of the blood flow is
diverted to essential organs such as the brain and the heart during a dive.
This is also the case for a torpid animal, thus allowing the temperatures
of these organs to remain normal while other parts of the body cool down.
So I think there is still a danger of a penguin going into prolonged torpor
if it remains in a dive too long.
Best wishes,
Stephen
***********************************************************
Dr Stephen Ambrose
Research Manager
Birds Australia (Royal Australasian Ornithologists Union)
Australian Bird Research Centre
415 Riversdale Road,
Hawthorn East,
VIC 3123.
Tel: +61 3 9882 2622
Fax: +61 3 9882 2677
Email: S.Ambrose <> (at work)
<> (at home)
************************************************************
|
