Re: The ultimate cause of aging

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.

You are correct that there can be a selective advantage in having more
offspring earlier, in which case there may be a tradeoff between spending
energy on offspring with increased risk of mortality vs. conserving
energy to reduce risk of mortality but thereby delaying offspring
production.



--
Alias Ernest Major

.

Relevant Pages

  • Re: The ultimate cause of aging
    ... There is a resource conflict between maintenance and reproduction, ... So evolution starves maintenance mechanisms and puts its resources ...
    (talk.origins)
  • Re: The ultimate cause of aging
    ... There is a resource conflict between maintenance and reproduction, ... So evolution starves maintenance mechanisms and puts its resources ...
    (talk.origins)
  • Re: Replicators
    ... Humans and other animals are self-replicating. ... One interesting thing about human rates of reproduction, ... reproductive rates fall below replacement levels. ... And determines how many resources are applied to repair, ...
    (sci.space.policy)
  • 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)
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