Re: Elephants vs mice (fwd)

[Bernard L Cohen <blc+@pitt.edu>]

On Wed, 9 Jul 1997, fhf wrote:

> 
> 	Cancer is a rather rare disease in young people and we are much more 
> likely to get the condition later in life. I submit the hypothesis that 
> the general time and likelihood of onset of cancer is 'programmed' 
> genetically as part of a general biological mechanism which has the 
> effect of limiting the lifetime of members of a species.

	--With the exception of some humans in this century, I doubt if
cancer has ever been an important cause of death in any animal. Even today
in underdeveloped countries, it is very unimportant. For example, in
Ghana, it doesn't even rank in the top 15 diseases for reducing life
expectancy. It is also difficult to understand how evolution can be
important in determining our present defenses against cancer because even
our offspring are ordinarily mature before we get cancer. Living to ages
when we get cancer must have had a negative influence on survival of our
species. 

>       When mice, humans and elephants live long enough to develop 
> malignant cancers, they develop them when the genetic programming of the
> animal withdraws the naturally efficient protection. 
>