> Phosphor wrote:
>>
>> also our lifestyle in
>> terms of brain activity must be about
>> 20 times more energy-consuming than
>> paleos.
>>
>I don't know. I think hunting, gathering,
>music making, story telling,
>tool making, surviving and living
>outdoors might use a person's brain
>even more than what's happening for
>a lot of people these days. That's
>the sort of use the big brain evolved
>for in the first place. Maybe
>people now tend to have more stress
>rather than more brain activity.

>Hilary

Hilary's speculation here is consistent with my observations in Papua New
Guinea in the 1970s and of Western suburban life in the 2000s.  There
appears to be a sort of Parkinson's Law working whereby culture expands to
fill in the space available.  Living in a land of resource abundance, the
PNG highlanders had evolved a complex matrix of ritual for young people to
progress to adulthood.  Believe me, it was intellectually challenging with
a massive demand on memory and the application of principles to
behaviour.  Lasted for about ten years, too.  To cap it off, the older
women, whose role in economic production was less critical, devoted their
time to the mastery of an arcane second language which was so complex and
replete with metaphor that no-one other than other matriarchs could
comprehend it.

BTW, this is moving off-topic and probably belongs over on the
Evolutionary Fitness list.  I'd be happy to continue it there.

Keith