Subject: Lungs and blue whales
Dagmar Fertl (Dagmar_Fertl@mms.gov)
Tue, 29 Dec 1998 13:49:15 -0500
I will be most obliged if you could provide me with this info? What
is the reserve lung capacity of a blue whale?
My e-mail address is "Sudheer" <pipl@vsnl.com>
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Hello there. Your question had me rifling thru some of my marine
mammal reference books at home during lunch today. Pardon me for a
long explanation to your question, because I'll need to refresh your
biology/anatomy terminology.
First, there is no such term as "reserve lung capacity". I believe
what you are asking for is "residual capacity", which refers to the
gases in the lungs that are not fully exchanged during a breathing
(I'm assuming you understand the basic principles of exhalation and
inhalation). Humans during breathing only exchange 10-15% of the air
in their lungs with each breath; whales and dolphins have a much more
efficient exchange of air at 80-90%. The lung capacity of a blue
whale of course depends on its size, but will probably be a maximum of
2,000 litres of air (this compared to the max of 4-5 litres of air for
a human). What's interesting is when you look at the ratio of maximum
lung capacity to body weight (compared to terrestrial mammals), a
rorqual's (like a blue whale) ratio of lung capacity to body weight is
half that of its relatives on land.