Xavier DRAYE <draye at gena.ucl.ac.be> writes:
>>Is there any reason to suppose that there is a correlation between body
>>size and longevity?
>>In mammals, Sacher (1978) found a functional relation between longevity and
>some anatomical and physiological dimensions (body size, body weight, brain
>size, etc). As a noticable exception, Peromyscus leucopus lives 2.5 times
>as long as Mus musculus, although both have similar body sizes.
The correlation between body size and maximum life span potential
(mlp) was studied in a paper entitled "Antioxidants and Aging", by
Richard G Cutler, Am J Clin Nutr 1991;53:373S-9S.
Quoting from the abstract, "...a positive correlation in the tissue
concentration of specific antioxidants with life span of mammals was
found. These antioxidants include superoxide dismutase, carotenoids,
vitamin E, and uric acid."
The paper included many graphs showing different mammals levels of
antioxidants vs life span. Most animals with low levels of antioxidants
were small animals. There were numerous exceptions to the proposed
correlation between body size and longeveity. Example: horses and cows
are larger than humans yet live less than half as long.
I think any observed trend toward larger body size leading to longer
life is secondary to plasma antioxidant level.