[ExI] [GRG] NewAbs: The Phenotype of IQ is Polygenic x 1, 000 Genes

[BillK]

On Wed, Aug 10, 2011 at 8:05 PM, Damien Broderick wrote:
> Here is a notion that probably has cropped up (or been crushed resoundingly)
> in the literature: despite the principle that evolution is blind to
> phenotypes once they're past reproductive capacity (due allowance made for
> keeping grannies alive to tend to babies, teach them to speak, etc), I
> wonder if some apparent instances of "deterioration" might actually be
> adaptations promoting the survival of one's lineage.
>
> It occurs to me that in a highly intelligent and memetic species like ours,
> memory management in the old (you can't remember what you ate this morning,
> but vividly recall the nutritious summer of 1887 or the brutal cold snap of
> 1922) might not be [entirely] an entropic accident.
>
> The current vital generations can be depended on to store recent events and
> trends, and maintain the liturgical coding of what's happened to the tribe
> and environment for many hundreds or even thousands of years--but perhaps
> sharp memories that retain hazard and opportunity information from 50-60-70
> years ago, if treated respectfully by the young, were beneficial in our
> preliterate EEA. If the maintenance cost of retaining full memory in old age
> is too great, perhaps early memories are given special care by the brain?
>
>

I hae me doots, Captain.

You say 'despite the principle that evolution is blind to phenotypes
once they're past reproductive capacity' then propose something that
depends on that premise.  If the effect exists it must be something
that evolution is blind to.

Current theory is that when pre-history humans were evolving they had
a life expectancy of around 30 years, with 50 years being exceptional.
More significantly, women had a lower life expectancy because of the
dangers of continual childbirth. So the effect should be present less
in women than in men.

I don't see how evolution could have generated a beneficial effect in
70 year old humans at a time when 70 year old humans didn't exist.


BillK