On Mon, 12 Mar 2001 16:20:17 -0400, matesz <[log in to unmask]> wrote:

>On Mon, 12 Mar 2001 05:51:45 -0500, Amadeus Schmidt <[log in to unmask]>
>wrote:
>
>> The ice age environment of most hominids
>> will have been close to today's !Kung of Africa.
>
>Do you have a reference substantiating this assertion?

!Kung Koisan land is a savannah/steppe with bushes, some trees and little
water (one of the last National geographic covered Koisan in the german
edition).
This is the landscape that results for a very long time, when tropical
rainforests develops into a dry kind of vegetarion, like it happened in the
times of glaciation.
Looks like this: http://www.esd.ornl.gov/projects/qen/afr(22-.gif
Then, in the thermals which ocuure from time to time (all some 30-60k years)
all developes back direction rainforest.

I refer primarily to Africa, because this is the place where it is likely
that the evolution of our anchestry (not of all humans) occured.
This is the place the first real humans were found, ca 120,000 y back.
Neanderthals I'd regard as humans but they evolved in northern parts
(Europe) and they died off / not related.
In the picture, you see that africa was very well seperated from the north
by an extreme desert.

>>
>> I note that the above Cordain paleolithic macronutrient ratio
>> "Paleolithic: fat-22% protein-37% carbohydrate-41%"
>> sets the protein ratio to the highet bearable protein part.
>> 37% is close to protein toxicity.
>
>Do you have a reference substantiating this assertion (re. the 37%)?

Just do a search on paleodiet on "protein toxicity"
or "protein poisoning". Since many years there are a plenty of references.

Like:
" (also 40  % of energy)...
"Since the maximal protein ceiling in humans averages about 35% of total
"energy  (4), ...
(4) is:  Cordain L, Brand Miller J, Eaton SB, Mann N, Holt SHA, Speth JD.
 Plant-animal subsistence ratios and macronutrient energy estimations in
 worldwide hunter-gatherer diets. Am J Clin Nutr 2000;71:682-92.

>> In a savannah I think this is rather optimistic in favour of the fat.
>> Consider availability compared to carb availability.
>
>What are the edible wild carbs you envision humans eating on a savannah?
>That would supply a diet > 50% carbs?

If you read http://www.price-pottenger.org/Articles/Aborigines.html
and skip the first hunting emphasizing part, you reach what kinds of plants
aboriginals ate.
"gathered seed, fern roots , grass potatoe, nuts" and much more.

Most seeds and roots are low in fat (1-3%) and moderate in carbohydrate,
so you get with a reasonable amount of energy (volume 2-6 kg) a protein
intake , which is relative high, compared to high carbohydrate food of
today. Perfect to live upon if you have some time to eat that much.

Then, there are fatty seeds. Primarily nuts, and certain smaller seeds
(sesame and hemp has 50% fat). These have most of the carb part *replaced*
by fat. With a reasonable amount of energy (volume 300-600grams) you get
high protein but slightly less than from vegetables.
Perfect to live upon this, since a minimum carb comes with it.

Then, the wild game is nearly a protein only resource. It's a lousy fat
resource (2-4%). A reasonable amount of energy would require to eat more
protein as the human physiology can stand. It has some vitamin-rich tissues
as advantage, particularly the liver. Which could be of advantage in regions
low in carotene rich plants , or generally for food shortages.
To live upon wild game is possible only in regions, where enough fat
is available with it.

The real main paleolithic staple I see as a mix of the two plant types.
With animals (preferently small like insects) as an add on,
from 1-2% up to the percentage of the protein ceiling
(37% kcal from protein, but protein from nuts and vegetables included).
The animals are not mandatory, just for variability, personal preference and
in times nothing else was available.

This was for warm and dry landscapes like "our" Africa.

For northern regions the horse can be saddled the other way round.
Animal meats (max 37% protein) demand 63% calories of energy from fat or
carb. If they can come from the animal's fat, you can live.
Otherwise they have to come from plant fats or carbohydrates.

That's the macronutient view you requested.

Amadeus

>
>Don