Re: Why are we allowed to age?
Dan Hook (guldann@ix.netcom.com)
Thu, 12 Jun 1997 17:49:18 -0400
This question is easy enough to answer, at least in females of the human
species. Menopause actually helps genes in a primitive setting because the
female is able to participate in activities that help the survival of grand
children and other relatives (remember the whole tribe is related). Old
members of tribes (male or female, but usually female because they live
longer) are also valuable because they have a great deal of knowledge. The
lived through that hurricane fifty years ago so they know how to survive
the next one. They know what plants can be eaten when the staple food is
unavailable. It would be most unfortunate if this knowledge was lost in
child birth.
It's important to remember that organisms can affect the survival of their
genes after they have reproduced. This can be a force for extending life
spans. The fact that certain things help in early life during the
reproductive years hurt in later life (for example, limited cell divisions
as a prevention of cancer and perhaps faster growth at the expense of
sustainability) is possibly more responsible for death, at least among
humans, than uselessness to genes. Evolution is a balancing act where
benefits must be weighed against costs, and the end result is the life span
we have now.
Dan Hook
guldann@ix.netcom.com
----------
> From: Hal Finney <hal@rain.org>
>
> The real mystery then is why genes allow the reproductive period to stop
> rather than working harder to extend fertility. Actually men are often
> fertile into their 60's and even beyond, so this discard-the-body theory
> doesn't explain why so many symptoms of aging show up before then.