I decided to come back to the board to try one more
time to guide the discussion in a different direction.
If I don't succeed it will most likely be my last
post. I needed a break from the computer, the
repetitiveness, lack of understanding and
aggressiveness. I received a few personal e-mails,
showing that at least some people appreciated my input
on the board. I will try to clarify a couple of
subjects which might have caused some confusion.
Unfortunately, I don't have access to a lot of good
information, but I will try to keep the information I
need for backup as basic as possible, so that there is
little chance for mistakes. And if anyone can proof me
wrong, please tell me, since I love to learn more.
Further I will just use the logic, possibilities and
impossibilities of natural selection.

I will definitely not reply to Kirt with quotes
anymore, since that seems to end up in arguing about
extremely uninteresting subjects. I really don't want
to discuss about thriving, surviving and being healthy
or not, since this is all way too much a matter of
personal opinion and anecdotes. We do not know how
people would have done on a raw vegan diet in our
past, simply because it hasn't occurred anymore since
we moved out of the tropical areas. We started using
other food sources, probably because we left our
original habitat due to population pressures or simply
because we were able to. It is likely that the
necessity of using other food sources turned to habit,
or maybe we just liked the new foods or simply the
variety. Anyway, meat eating became established and an
accepted part of our diet. This does not necessarily
mean that it is the best choice for our health or that
we become sick when we leave vertebrate meat out of
our diet. Whatever you may think of this, it is an
endless and useless debate. You simply never know if
you have the ideal diet, because it is always possible
to feel even more healthy. There are plenty of people
sick with meat in their diet and their are plenty of
people sick without it. And what should be considered
healthy? Are you extremely healthy when you can
bench-press hundreds of pounds? Who knows: maybe you
die ten years younger. We all know that exercise is
important, but what if you overdo it? And again, being
healthy and being a successful reproducer, which is
the only thing that counts for natural selection, are
not the same thing. And then there is the social
aspect of eating meat: how many people eat meat just
because they don't want to be different, even though
it might make them feel worse? So I am really not
interested in talking about that subject. What I am
interested in is figuring out how evolution works and
what we are adapted to and what not.

The whole discussion about age at death was also just
a ridiculous distraction from the actual topic, which
was if there is a causal relationship between meat
eating and brain growth. I listed a number of
objections in my post of 11/21 and in one age at death
was mentioned; the other points were conveniently
ignored. The whole discussion about brain size reminds
me of an old wives tale in the Netherlands about
storks delivering babies to expecting couples. Storks
and birth rates declined at the same time. Does that
mean that it is a causal relationship? It also reminds
me of a chapter in one of Stephen Gould's books, in
which he described how about a century ago some big
headed (male) scientists wanted to figure out the
relationship between brain size and intelligence,
particularly to confirm the supposed superiority of
males, since males have on average quite a bit larger
brains than females (by the way: I have an extremely
large head and never ate much meat). The big question
is of course: what is the function of having large
brains and is it eventually still going to be an
advantage to have even larger brains? Causal
relationships are hard to establish and it is
absolutely absurd to claim a causal relationship
between traits in the distant past. Development of the
brain can be the cause of a lot of different factors
than nutrition. Starting to eat meat coincides with
extensive use of tools, getting used to new habitats
and food sources, needing to develop new techniques
for obtaining food (hunting) and no doubt several
other factors. Predators tend to have larger brains
than herbivores because they need to be able to
perform a more diversified set of behaviors to obtain
their food. Humans started to hunt too, so of course
their brain grew accordingly. It is totally
unscientific to assume that the brain growth is
dependent on the nutrition of meat, since it coincides
with many changes in behavior, habitat and
exploitation of new food sources. Comparing the brain
evolution of herbivores and carnivores and drawing
conclusions from that about brain growth in humans is
an absurd simplification and totally ignores the
unique circumstances of human evolution. And besides:
I don't think there can be any doubt about the fact
that brain expansion in humans was already in progress
before we started eating meat. We also have to take
into account that brains can even expand on "bad"
nutrition as long as the selection pressure on brain
growth is strong enough. And I even heard from
somebody that Neanderthal people had larger brains
than modern humans, so how does that fit in the
meat-brain growth picture?

Obviously there is still a lot of misunderstanding
about human evolution and the inhibition of natural
selection. Simply spoken: the more we started using
technology, the higher the chances are for inhibiting
natural selection. Some people conveniently didn't
understand an obvious example of this inhibition. This
is the fact that we have been moving away from the
tropics for probably already more than a million
years, but we still haven't developed any fur to
protect us from the cold. This is because we used the
fur of other animals to keep us warm. This effectively
prevented natural selection, causing us to still have
a tropical make-up. Another obvious example is the
lack of population control: in my opinion it is very
possible that humans started moving out of their
original habitat because of population pressures,
since we effectively cancelled out a serious
proportion of the naturally occurring deaths. Of
course this is not as strong in prehistoric times as
it is now, but it still is a factor that should be
taken in consideration. And if the inhibition of
natural selection is possible with fur and population
control, why wouldn't it be possible for food choices?
If we eat something that we are not adapted to, does
that mean that we will die? Does it mean that our
reproductive success is going to be affected? I highly
doubt it. We have to keep in mind that natural
selection for physiological traits is not likely to be
as strong as on morphological traits, since
morphological traits have a more direct link to
survival. This is why our ancestors, who were still
mostly frugivorous in our original tropical habitat,
might very well have looked totally different than
modern humans, but that their dietary adaptations
might not have changed very much.

Our meat eating habit started when we started
manipulating our environment in a serious way, which
means when we started using tools. This is generally
accepted to have started with Homo habilis about two
an a half million years ago. Saying that extended
canines in humans are not important for meat eating
while every meat eater in the animal world has them,
shows ignorance to me. It is like insisting that we
have to live in the water, just because we can swim.
The fact that Gorillas, who barely eat meat, and
animals like flying foxes, who are totally
frugivorous, have extended canines, is irrelevant,
since the fact remains that all animals that do eat
meat have extended canines (Remember: that every cow
is an animal, doesn't mean that every animal is a cow;
this seems to be a hard concept for some people). The
big question that remains is: why did the extended
canines of our ancestors disappear about 5 million
years ago? I don't know, but it is unlikely that it
has anything to do with the development of speech,
since that has been an extremely gradual process, so
unlikely to be subject to strong selection pressures.
Fact remains that the extended canines did disappear
and that doesn't support a meat eating adaptation.
Like I said before: they did not disappear because of
the use of tools, since those have only been in use
for two and a half million years.

Another topic I would like to bring under the
attention is that in my opinion diet choice should be
based on the principle that if everybody eats the way
that you do, it should be a sustainable choice, simply
because if your way of eating means that other people
starve or other species become threatened, it can not
be considered ideal. Even if we would get rid of all
farming and animal husbandry, a modern hunter/gatherer
lifestyle would not be sustainable. This is because
the inhibition of the normal natural selection process
has taken away all possibilities for population
control. There would simply be way too many
hunter/gatherers for the available wildlife. Obviously
we need a different approach. Focusing on the
hunter/gatherer fase of our evolution and simply
ignoring the final stages of the evolutionary process
is not a solution! And by the way: I am not ignoring
the hunter/gatherer fase of our evolution: I am simply
trying to show that we are not adapted to it (see
canines), even though we have lived like that for a
long time.

Another problem with modern meat eating is that our
world is highly contaminated and that this brings a
new form of "natural" selection. Since carnivores are
on the top of the food pyramid, it is obvious that
they accumulate a lot of contaminants. Eventually this
will lead to a strong selection pressure against meat
eating, favoring the herbivores on the planet. Even if
you pick your meat from the best sources, this process
is unavoidable.

Modern society also brings the possibility for rapid
evolution of diseases, which makes carnivores even
more vulnerable. I still haven't had any satisfactory
reply why RAF eaters are assuming to be immune to
those diseases, like mad cows disease. Another point I
haven't had a satisfactory reply to is that RAF eaters
assume that we are adapted to eating meat and not to
cooking food. How can they justify this? And don't
come with the answer that we have been eating meat for
a much longer time than cooking our food, since time
is not very important to evolution; selection pressure
is the key factor!

Take care, Arjen



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