Re: The ultimate cause of aging

Ernest Major wrote:

In message <VrnAj.1691$y83.1188@trndny06>, Bill Morse
<wdNOSPAmorse@xxxxxxxxxxxxxxxx> writes
Tim Tyler wrote:

Iain wrote:
On Mar 5, 9:34 am, Tim Tyler <seemy...@xxxxxxxxxxxxxx> wrote:
Iain wrote:
This beard's man has an opinion on the subject:

"Aging is a product of evolutionary neglect, not intent."
http://www.youtube.com/watch?v=wEyguiO4UW0
Evolution /does/ care.

There is a resource conflict between maintenance and reproduction,
and reproduction considered to be more important. [...]
So evolution starves maintenance mechanisms and puts its resources
into making babies - naturally resulting in senescence as damage
fails to get repaired.

Yes, there's no conflict between your point and AdG's. The body puts
its resources into the baby-making function and so *neglects* the
functions that would increase lifespan. The selection pressure is on
baby-making, and *off* longevity (which statistically isn't important
to baby-making -- most historical instances of baby-making happen
before 30). It's the exact same point.

You seem to be using the "to fail to carry out" definition of neglect.

Neglect /usually/ means:

* to pay no attention or too little attention to; disregard or slight:
* to be remiss in the care or treatment of:
* to omit, through indifference or carelessness:

[Definitions from http://dictionary.reference.com/search?q=neglect]

...and from the fact that "neglect" is contrasted with "intent"
here, those are clearly the kinds of definitions that are implied
here.

It's not as though evolution "forgets" to fund the maintenance
machinery. We know from studying CR that it even bothers to
construct some of it - and then doesn't put "fuel" in - because
the "fuel" is better spent on reproductive ends.

The underfunding is calculated and deliberate - the result of
*intent*, in other words - and is not the result of some
omission, or lapse of attention.

Is is not that evolution doesn't care about long lifespans.

It actively dislikes them - because of the cost involved
in attaining them - and the fact that it has other
expenditures to consider.

Wrong. Evolution is perfectly happy to support long lifetimes, and there
is no cost involved in attaining them. The only thing limiting long
lifetimes is the inability of selection to select for something it can't
see.

I disagree that long lifetimes have no cost. For example, to attain a
long lifetime requires avoiding death from cancer in the intervening
period. This requires lowering the probability of suffering from cancer.
This can be achieved by, at least, improving DNA error correction, or
eliminating pre-cancerous cells as they occur. Neither strategy seems
likely to be cost free.

Good point, but as I note in my follow to Tim there is also a cost in
reproducing a new large complex animal. Two comments here. One: bristlecone
pines achieve lifetimes of >1000 years without succumbing to cancer. Two:
whale sharks achieve lifetimes of 100 years with 500 times the number of
cells in their bodies as humans. So one suspects that the costs you discuss
are not huge.
--
Yours, Bill Morse

.

Relevant Pages

  • Re: The ultimate cause of aging
    ... Is is not that evolution doesn't care about long lifespans. ... It actively dislikes them - because of the cost involved ... Evolution is perfectly happy to support long lifetimes, ... is not limited by maintenance cost but is instead limited by statistics. ...
    (talk.origins)
  • Re: Thermodynamic vs. Informational Entropy - for Dr. Marc Buhler
    ... How can those bacteria evolve without a germline? ... Odd, isn't it, that by your definition of evolution only sexually ... Using only clonal reproduction bacteria can ... The population of immune cells ...
    (talk.origins)
  • Re: Thermodynamic vs. Informational Entropy - for Dr. Marc Buhler
    ... How can those bacteria evolve without a germline? ... Odd, isn't it, that by your definition of evolution only sexually ... Using only clonal reproduction bacteria can ... mutation and selection during the lifetime of the host dies with the ...
    (talk.origins)
  • Re: Felsenstein and reproductive excess
    ... > some strange definition of "reproduction" that I cannot grasp. ... from their population genetics heuristic exercises: TOTALS. ... Any total cost has to be paid ... on just a relative cost of substitution which may not have to be paid ...
    (sci.bio.evolution)
  • Re: Sexual Reproduction Disproves Evolution
    ... reproductive systems useless, and the organism would become extinct. ... The physical, chemical, and emotional systems of the male and ... random, evolutionary processes, or sexual reproduction was designed by ... George C. Williams, Sex and Evolution ...
    (talk.origins)
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