First of all, re your reply to William:-
Actaully, the notion re Eskimos and health is only held by some. I'm afraid
there is an unfortunate tendency among a number of followers of Weston-
Price Dieters and Paleodiets to assume that there was a sort of idyllic Shangri-
La-like period, either before 10,000 BC or up to the point where white
settlers arrived, depending on which dietary theory one follows. In truth,
however, many such tribes were hardly free of disease, and most died long
before the age at which modern peoples start getting degenerative illnesses,
as "life was "brutish, nasty and short".
http://www.ncbi.nlm.nih.gov/pubmed/9740301?dopt=Abstract
Re your claims:-
1) It is, indeed, entirely irrelevant as to whether human hunter-gatherer tribes
have ever been on a 100% raw diet(though I've heard someone making recent
claims re the Tasmanian Aborigines in that regard). First of all, it's highly
inaccurate for any Paleodieter to draw conclusions from modern hunter-
gatherer tribes as they are, in virtually all cases, nothing like the diets of our
Palaeolithic ancestors. The Masai, for example a typical hunter-gatherer tribe,
eat lots of raw dairy for example, while the pre-contact Maoris would go in for
grains like manioc etc., none of which were found in palaeo times.
re your comment"
Plus, if cooking was a serious risk
>to health, as William sometimes suggests, we would expect to find at least
>one hunter-gatherer tribe over the last 100,000 years that only ate raw,
>given that in the wild only the fit tend to survive and procreate":-
Again, this is based on a false premise. First of all, like most raw-foodists, I do
not actually claim that "cooked-food kills!"(LOL), merely that it causes
deterioration and ill-health, over time. I mean cooked-food is not on the same
scale as cyanide, after all. Perhaps comparing cooked-food to a mild form of
arsenic(or a pack of cigarettes a day) would be more appropriate.
Secondly, as soon as humans invented fire, natural selection was no longer a
driving force(or even relevant) for humans once fire was used, initially, to
scare away natural predators(wildlife fear fire, after all) which would otherwise
have preyed on them. Using fire for warmth would also have kept many alive
who would otherwise have died from cold/exposure or other problems. Indeed,
it could easily be argued that natural selection became a significantly reduced
factor for humans once they gained much greater intelligence than their
opposing predator species.
Also, as long as a certain harmful practice doesn't kill you before you reach
the time when you pass on your genes(c.20 years for most tribespeople?) that
practice will still be passed on regardless, unaffected by natural selection. To
give a more modern example, cigarette-smokers haven't been wiped out by
natural selection despite large proportions of the population indulging in
smoking in countries such as Greece etc., as they manage to breed before the
deleterious effects start really ruining their health.
Thirdly, if you want a real-life example of how healthy it is on an all-raw diet,
one only has to look at local wildlife in unpolluted areas., which are free from
many diseases which are specific to humans(and, of course, domesticated
animals fed on low-grade, processed diets).
What is most interesting is the fact that, as modern diets become ever more
processed/heated in the West, sperm-counts and egg-fertility of women are
all dropping like a stone, resulting in lower birth-rate and more usage of
technologies designed to get around such problems of sterility.
Re advent of cooking:- Unfortunately, Wrangham's ideas re early cooking have
long been discredited. If you google archaeological info/articles, you'll find that
most anthropologists do not even seriously consider Wrangham's notions(eg:-
"Yet he, Michigan's Brace, and most other anthropologists contend that
cooking fires began in earnest barely 250,000 years ago, when ancient
hearths, earth ovens, burnt animal bones, and flint appear across Europe and
the middle East. Back 2 million years ago, the only sign of fire is burnt earth
with human remains, which most anthropologists consider coincidence rather
than evidence of intentional fire. " taken from:-
http://cogweb.ucla.edu/Abstracts/Pennisi_99.html
This is the problem. The only times when absolute, incontrovertible proof is
found re cooking being started was c.250,000 to 300,000 years ago, re
hearths being found, with widespread cooking being found c.100,000 years ago
among the Neanderthals. Before that time, all one finds is bits of burnt sticks
and burnt earth, all of which , as most anthropologists point out, can easily be
caused by natural wildfires, started by lightning. Saying that such sticks must
have been used for tubers is merely wild conjecture.
The 500,000 figure cited is clearly related to the Zhoukoudian Caves find, but
that's an old theory from the 1930s and was already discredited as much as 10
years ago by scientists:-
"Since the early 1930s scientists believed a cave in China rich with fossil
remains was the place where humans first controlled fire as long as 500,000
years ago.
But a new chemical analysis challenges this view and concludes Peking man did
not actually conquer fire in the cave, which is located in the southwestern
suburbs of Beijing in Zhoukoudian, researchers said Thursday.
"This site doesn't prove the use of fire," said Clark Howell, a paleontologist at
the University of California at Berkeley, who did not work on the study but who
is familiar with the cave. "There was certainly no burning in the cave itself."
In the study, published in the journal Science, a team of researchers said a
lack of ash and charcoal remains at the cave was proof that early Peking man
did not use fire. "
"But a new chemical analysis challenges this view and concludes Peking man
did not actually conquer fire in the cave, which is located in the southwestern
suburbs of Beijing in Zhoukoudian, researchers said Thursday."
taken from:-
http://www.trussel.com/prehist/news78.htm
The trouble with the Zhoukoudian caves was that burnt bones were washed
in from outside , thus giving the erroneous belief that fire was controlled by
Peking Man,:-
"The association of fire with faunal remains, stone-tools and hominid fossils is
far from conclusive and is most likely the result of noncultural postdepositional
processes (Binford and Ho 1985, Binford and Stone 1986)." And this point, re
possible contamination of sites has been cited as why other similiar, earlier
finds are also considered of questionable origin.
By the way, that Steven R James article kind of supports my view and includes
the above statement re "noncultural postdepositional processes"). Throughout
the article, it's made clea that the evidence from zhoukoudian is "inconclusive"
and that earlier claimed dates for fire/cooking are fraught with controversy etc.
Re tubers:- I think we can both agree that tubers were unlikely to have
become a serious part of the human diet until the megafauna were mostly
wiped out c.40,000 years ago.
3) Re wrangham's notions:- Wrangham has already been proven wrong re his
linking of cooked-tuber consumption and greater human brain-size. For that
theory to work, humans should have increased their brain-size in the Neolithic
when they turned to starchy foods (tubers are a starchy food) in much
greater quantity than in palaeolithic times. Yet average hominid brain-size fell
by a stone. Plus, there are 2 points in the human evolutionary history, where
big increases in brain-size occurs. Wrangham tries to account for the increase
in homo erectus' brain-size 1.9 million years ago, but forgets that homo habilis
also increased in brain-size by a similiar amount. Since the greater brain-size
in homo habilis AND homo erectus each coincide with a greater increase in the
consumption of meats in their diet, that is a far more plausible explanation
than the Wrangham claims re cooking. And even Wrangham himself grudgingly
admits that he has only circumstantial evidence to back up his claims:-
http://www.scienceagainstevolution.org/v12i5n.htm
But, the big problem with the whole notion re cooking having a major influence
on human evolution is that only 1 date really fits in with this notion(1.9 million
years ago as no one seriously would ever consider homo habilis as having
invented fire even further back). So, given that wildlife function quite well
without needing cooked-food to survive, it's more difficult to promote cooked-
foods as being necessary for health, and, given the relevant scientific data on
toxins in cooked-foods, it's at the very least quite harmful.
Geoff
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