Re: Cornering the causes of aging

From: Damien Broderick (
Date: Mon Jul 10 2000 - 22:03:52 MDT

At 01:13 PM 10/07/00 -0400, John Clark wrote:

>if you have enough offspring some will survive
>and the gene doesn't care which particular individual it uses to get into
the next


>The genes have "decided" that in a dangerous world finite resources could
be put to
>better use, such as growing fast and having lots of offspring and having
them early
>in life.

Well, no. In *some* species (or sub-species), it has worked out that way.
But puppy dogs and pussy cats have ample frequent litters, while humans
tend only to have singletons (and, if the nursery story tale is correct, so
do lions - `Just one... but he is a *lion*'). Many fishies spawn like mad
things. So there are lots of different strategies in the phase space.

> >*unless* the costs of maintaining its numerous
> >and specialised tissues are very much greater than throwing an adult
> >away and starting with ignorant near-copies
>I think that's exactly why evolution never thought it was worth the bother to
>come up with an immortal animal. Why do you think that explanation for aging
>is insufficient?

I'd like to see the mechanism, and the explicit cost/benefit chart. It
needs to show exactly why different critters sharing the same indices can
vary in lifespan by huge ratios - 1:10, etc. Maybe it's all in the ecology
and variant risks of predation. Or maybe it's mainly drunkard's walk - with
the geneplexes of many beasties staying back near the wall because, yes,
that's one viable way to do it, but more elaborate solutions are doing
quite okay too, way out there past the kerb.

Damien Broderick

This archive was generated by hypermail 2b29 : Mon Oct 02 2000 - 17:34:22 MDT