From M. A. Hosey
Surely there is a better reason for the pleural membrane in elephants
(8 September, p 17).
I’m a physicist, not a biologist or zoologist, but I’d
estimate the weight of an average healthy adult African elephant lung to be
between 60 and 80 kilograms. That’s a lot, and I don’t believe a standard
pleural cavity could support such a loose heavy structure against the force of
gravity. Matters get worse when the elephant runs.
I can’t think of a better “design” than to support the entire lung with a
huge number of filament-like tendons in the form of loose connective tissue. I’d
also expect the larger dinosaurs to have had a similar structure. And perhaps
dugongs share the elephant’s physiology, not the other way about.
East Kilbride
