Thanks for your candor, Bob. Now I know where you are coming from. That's
what I was interested in. Some comments.
>First of all, is modern man the endproduct of millions of years of
>evolution? It sounds plausible, but I don't know.
All the evidence points to this overwhelmingly, and that all other
creatures are also the endproduct of millions of years of evolution. There
is of course probably no absolute proof of anything. However, if one is
going to be rational, one looks at the evidence and goes where it takes
them.
Part of my question to you was to see if you had any other way of
explaining the succession of forms in the fossil record to explain how
adaptation might occur. Again, unless one posits divine cosmic intervention
to create new forms out of thin air, or importations of spores from outer
space that rapidly evolve in the twinkling of an eye to fulling evolved
successor species to the ones that go extinct, there is little alternative
to the darwinian view which only becomes strengthened over time. Especially
with the new genetic-clock dating techniques that show extremely strong
correlations with dates as known from the geological fossil record. This
even more strongly suggests genetic continuity in the succession of fossil
forms.
>If we did evolve, and evolution means adapting genetically (when possible)
>to >inimical environmental influences, what is the rate of adaptation?
First, the labeling of "environmental influences" as "inimical" is in some
sense a prejudice, since *all* environmental influences that have ever
given rise to any species since the first bacteria were adaptations to
influences different from their previous adaptation. In this sense they are
indeed inimical, but without these inimical influences, there would be no
"selection pressures," no evolution, no new species. Evolution is a process
of organisms adaptating to shifting influences.
The rate of adaptation itself depends on selective pressures. The newer
interpretation of the fossil record suggests that the reason for all the
"gaps" is that organisms do not change that much when the environment is
stable, but they can change rapidly when the conditions shift, producing
new forms quickly. I.e., this is the more recent refinement to the basic
darwinian theory, known as "punctuated equilibrium." Eldredge and Gould who
first put forth this new interpretation to better explain the fossil record
have suggested the evidence would yield a rate of somewhere between 5,000
and 50,000 years for a new species to arise from a preceding one.
Population geneticists tracking gene flow and using various genetic clocks
say it could be somewhat less. All depends on how consistent the selection
pressures are.
>I don't know. Dr. Wardovski says 10's of thousands of years (maybe less); Dr.
>Guy-Claude Berger says millions of years [Manger Vrai]. Who's right?
It's not *me* who came up with this figure, I am quoting modern-day
theorists and have given references in my H&B interviews. I have not read
Manger Vrai except to page through it, but I have looked at the pages where
Burger says millions of years. If memory serves, he is looking at metabolic
mechanisms that evolved a long time ago that are common to many creatures.
This doesn't address the question of the more recent incremental genetic
changes that result in new species.
>Does the evolutionary paradigm consider that what you call "genetic"
>adaptation >may be just as weakening to the species as an individual's
>adaptation to a >poison?
The word "weakening" is again a judgment of the mind as to what is a better
or worse form of adaptation. Adaptation just adapts to whatever behaviors
or environmental factors persist long-term, and produces different species
adapted to the different environmental/behavior niches they inhabit. The
result is the many different species we see around us, such as cats, rats,
turtles, frogs, apes, humans, bacteria, horses, elephants, bears, etc.
Evolution does not judge better or worse. Is it better to be a cat or a
rat? A whale or a dolphin? An ant or a termite? A human or a chimpanzee? We
would say human, but that is because we *are* human. From the point of the
whole, there is no better or worse. There is just difference.
>In other words, if we could suddenly presto-chango zip ourselves into
>whatever >environment we originated from, would we do better in that
>environment than we >would in a more modern environment to which we had
>become "adapted?"
Theoretically the answer is clear that we would do best in the environment
to which we are *most recently* *fully* adapted. But figuring out what that
is in the real world is a judgment call. Most people who have looked at the
question based on the scientific evidence would say that means probably not
much further back than, say, roughly 40,000 years ago. However, the last
10,000 years since agriculture puts the human species in the middle of a
transition to which we have likely only partially adapted. Or to which
certain human populations longest associated with agriculture may have
developed more recent adaptations (to grains, possibly dairy products,
which have even less of a history), which other populations may not have.
Pretty much everyone agrees that the species is in transition right now,
not in a stable period.
>In other words, in the individual who smokes tobacco, a type of adaptation
>>occurs, but it results in chronic disease and a shortened lifespan.
>Removal of
>the tobacco results in reverse adaptation, called withdrawal symptoms,
>and a partial restoration of structural integrity and lifespan
>potential. Does genetic adaptation work the same way?
No. This goes back to the difference between genetic change vs.
*functional* physiological adaptation (the individual organism trying to
adjust its homeostatic processes to cope with stressors). From what I can
tell having discussed evolution with a lot of different people just hearing
about it, this is probably the fundamental misconception about how
evolution works.
Functional adaptations like the body adjusting to tobacco smoke as best it
is able don't result in any genetic changes. They are temporary
physiological adjustments in functioning only. An individual is stuck with
the genetic "hand" they have drawn for life, and must then cope the best
they can by way of functional adjustments.
Your observation that it would be intelligent not to put oneself in an
environment or engage in behavior inimical to the genetic hand one has
drawn is one I definitely agree with. However, genetic change occurs
initially through random mutations in the germ cells (sperm or eggs) that
give rise to new *permanent* changes in offspring in how the organism
functions. Most of these mutations are harmful, and get culled out because
they are maladaptive, but every so often one arises that is beneficial and
produces improved adaptation and better survival or fertility rates. These
then get passed on to descendants. If the new mutation genuinely improves
adaptation--actually that's the very definition of "adaptation," then, yes,
it is permanent and once it spreads throughout the population, there is no
going back.
One theory that has not been possible to test yet is that there are
probably always a range of possibly advantageous but rare genes existing in
a few individuals that can come to the fore quickly when environments
change, so that a random hit-and-miss mutation (which may take a long time
to ever arise) is not strictly necessary. Evolution depends on variation
within the population, and some of this variation is not arrived at just by
recent mutations, but by pre-existing variations in rare individuals, who
are sort of like a "contingency fund."
>Should I eat a modern diet or the diet originally designed for our species
>>(whatever that is) in order to optimize health and longevity? Does
>anyone know >the answer to this question?
Theoretically, the answer is that it would be best to eat whatever diet
corresponds with the species' *most recent* evolutionary adaptation. The
term "original" diet is used most often by those who are into eating a
"natural" diet and go by the paradigm of returning to the species
"pristine" adaptation. Technically speaking, though, there is no *original*
diet, because all evolutionary adaptations are derivative of earlier ones.
The most recent adaptation is the one a species will be most closely
adapted to. But this is theory, because in real life, there are the
complicating factors you mention...
>Furthermore, environmental pressures are ever in flux.
>The pressures that prehistoric man was eating in relation to were
>different from the ones we are eating in relation to. It's all fine and
>dandy to say that we adapt to evolutionary pressures, but when the
>pressures themselves are constantly changing, what are we left with? A
>species that's always evolving, never "arrived."
Exactly! On the other hand, the pressures are not necessarily always
changing. Sometimes they are changing, sometimes they are stable. (This is
what the newer refinement of darwinian theory called "punctuated
equilibrium" is all about.) Right now we are in a period of punctuated
change since the agricultural revolution 10,000 years ago, but before that,
relatively speaking, things were more stable for hundreds of thousands of
years.
>But my biggest quibble with the paleolithic diet is simply this: Why
>should I emulate the dietary of a group of people that had an average
>lifespan of 30-40 years, when I could live on junk food and be likely to
>double that lifespan? I don't see where their diet did them any good
>whatsoever, or any reason to believe it would do me any good either.
>When you have constantly changing evolutionary pressures, constantly
>changing diets, a history of human abuse and maladaptation to every
>environment man's been involved with, how do you tease out the various
>factors and come up with anything meaningful? I don't know.
It's difficult, but not *that* difficult, as least as far as basics go. By
the same token, why should you emulate the diets of the agricultural people
who lived slightly less-long lives while eating considerably less meat than
the paleolithic people did? *Nobody's* lives were very long back then,
because of social conditions and occupational hazards of ancient life that
killed most people before their time: ongoing tribal warfare or accidents
or trauma, etc.
But there is no avoiding that today's longevity still derives from the
genetic hand we have inherited from these ancient people. It's not as if
our longevity has arisen in a vacuum due only to our way of life now. Since
humanity's genetic adaptation will have changed only slightly since those
times (the period immediately before the transition to agriculture), the
main differences between now and then are social conditions. The logical
assumption is that if you put those same people under today's "safer"
social conditions, they would also live long lives. After all, we inherited
their genes.
>I prefer to take the empirical approach, which is what Natural Hygiene
>does. What kinds of foods do people actually digest well and thrive on.
Fair enough. I agree in large part, but you and I disagree on what actually
works empirically when we look at real people.
But beyond that, we are operating from differing paradigms here. I trust
the picture from human evolution more since it has a 3 or 4-million-year
history of proving itself. You trust the modern epidemiological studies
more because they look at actual people today. There are sound reasons for
either approach.
Actually, though, I look at both, but I see modern epidemiological studies
constantly reversing themselves and only gradually through much trial and
error arriving at reliable conclusions. Epidemiological studies are
particularly prone to investigator bias because you can only answer the
questions you think to ask, which reflect the investigators' interests. One
real problem I have with most modern epidemiological studies--and I think
this would probably include T. Colin Campbell's China Study (although I am
not sure), is that the ones vilifying meat or animal protein as far as I
know are looking at products from domesticated, not wild animals. As the
Eaton research team has thoroughly documented, modern meat has 5 times as
much fat as domesticated (roughly 25% vs. 5% fat), and 5 times the
saturated fat, and virtually no EPA while wild game has significant
amounts. Modern livestock animals are in general not very healthy
animals--or at least kept from succumbing with antibiotics, or fattened up
with artificial techniques. I would contend this seriously biases the
epidemiological studies.
>The original hygienists of the 19th century tested various diets and
>found that raw vegan foods were less stressful to our organisms than
>non-vegan foods, cooked foods, refined and atificial foods.
I am not sure I would agree except for the refined and artificial foods.
What we see in the Natural Hygiene M2M in real life and what modern-day
Hygienic practitioners say is that most Hygienists in fact do better by
adding some cooked starch foods, such as legumes, potatoes, squash, grains,
and so forth. The vast majority do not thrive as well on a strictly raw
diet. And of course, some of us still eating otherwise Hygienic-style diets
have done better than we did before by adding some meat to our diets.
>So I try my best to live within my physiology and not to some hypothetical
>>historicalstandards, though I do keep an eye out in that direction.
Again, fair enough. My tack is the opposite, to live more in keeping with
our evolutionary adaptation and keep an eye out for the epidemiological
studies to perhaps make some adjustments.
Also as I said earlier, evolutionary adaptation is a "best-fit compromise"
to a "mix" of behavioral/environmental factors. If one wants to purposely
change that mix to include greater longevity via caloric restriction or
less meat for instance, at the expense of what might be a less happy life
for some (but not for others, perhaps not for you and Doug, for instance),
then I don't have any quibble with that. I myself am intending to get back
into a yoga practice again soon, and that's certainly not something we did
in our evolutionary past. I am not necessarily arguing for slavishly
following the evolutionary past because the process itself is open-ended,
and we are self-aware creatures who can make any choice we wish. I have no
problem with making adjustments based on one's objectives in life.
Again, all I am saying is that if by a "natural" diet one means to follow
our so-called "original" diet, then vegan/vegetarian diets are not natural.
And it seems highly likely to me that a diet based on our evolutionary
adaptation is going to be the best place to start from, but that depending
on one's objectives certain adjustments might enhance some aspects of one's
life. But if one does so, it also seems to me that to do so one would have
to be willing to take the hit in other counterbalancing areas that will
likely be influenced adversely due to the deviation.
For instance, those on caloric restrictive or raw-food vegetarian diets
with less meat may live longer but they may be so skinny, or might risk
having such a low sex drive, they just can't enjoy or do certain things in
life. (Low or no sex-drive, as well as continual hunger, are two of the
complaints sometimes heard from raw-fooders or strict Hygienists in the
Natural Hygiene M2M.) But they may not care either. The trade-off is
anyone's to make. We humans are an interesting amalgam of
instinctive/natural adaptations plus onoing technological add-ons arising
from our evolutionary predilection for tool-use. How do we consciously
optimize it all depending on our objectives is what it's all about, eh? So
in the end, go get 'em! :-)
>Satisfied? As I said, when I get it all figured out, I'll let you know.
Yep, thank you Bob!
--Ward Nicholson <[log in to unmask]> Wichita, KS
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