Re: chimps stronger than humans

On Apr 10, 1:48 pm, "James Howard" <jmh.anthropogeny....@xxxxxxxxx>
wrote:
First, thank you for you thoughtful reply.

I will answer these as a group; going back and forth just confuses matters;

Try to learn to use the attribution marks, that is what they are for.

well it confuses me when I read a mixed up post / response thread.  

IOW, you get mixed up when you make false statements and don't have an
answer
for the rebuttals.


My post
and your responses are all below this for reference.

No, I do not say "cold equals increased growth of brain and body."  I say
that higher DHEA allows living in the cold and extra DHEA increases growth
of brain and body.

Try again, you said: " Extra DHEA would provide increased growth and
development of the brain and body."
Cold has nothing to do with anything here regarding body/brain size.
Later Neandertals proved that, which you seemed to ignore. Hypotheses
make predictions and yours fails.


 I also suggest that situations that increase
testosterone, especially when boxed in, may cause an increase in overall
size.

Wrong, Eskimos and small Neandertals refute your own claims. Your
hypothesis
has no answer for this overall reduction through time.

 This is how I explain the very large gorillas and orangs that
occurred in the tropics.

So, if you are large in warm climates, it is because of DHEA, and if
you
are large in cold climates it is because of DHEA. If you are small in
cold climates
it is because of DHEA, if you are small in warm climates it is because
of DHEA.
There is no relationship in warm or cold climates for any of your
claims.

 The very large difference in males and females in
these groups is due to the increased male testosterone.

Please cite your source for that.


 This increase
occurs without the effects of cold causing increased DHEA.

Yes, called having your cake and eating it too. If you are large or
small,
warm or cold or if you have two different species living in the same
climate
of different sizes it is all because of DHEA.

With that in
mind, let us look at Boxgrove Man.  Boxgrove Man was found in England, a
peninsula at the time.

Well, Germany wasn't, Homo h has been found in many countries.

 I think it is very possible that Boxgrove Man
increased size may be due to the same effect of a group being relatively
isolated which increased testosterone and there was enough cold to select
for DHEA.  ...

Enough cold? Then what happened to the later Neandertals? They should
have
gotten larger than their ancestors, not smaller, according to your
reasoning.


so Boxgrove Man became very large with the combined effect of
testosterone increase and DHEA increase.

You don't seem to follow. Neandertals and Homo h lived in warm and
cold extremes
and those in Europe decreased in size overall through time. DHEA had
nothing to
do with it.


The Bergmann rule refers to animals actually being smaller farther north.  I
explained this effect by first suggesting the large mammals got big as
selection for DHEA occurred.   I then suggested that living farther north
will require more DHEA for warmth generation.  ...less DHEA for growth and
more for warmth reduces overall growth.  Boxgrove man lived in "relative"
warmth and later, Neandertal, lived more during the ice ages so I suggest
their smaller stature may be due to the use of some of their DHEA for
warmth, so Neandertals were smaller.   Again, I think the tropics produced
some large animals as a result of increasing testosterone, that is, cold was
not required.

Large and small lived in both warm and cold climates. Turkana Boy was
large,
the Olorgesailie fossil was small---- same part of Africa.


Chimps and humans split off together.

They evolved different paths away from the same common ancestor.

 I suggest this is due to the increase
in maternal testosterone which can be seen as less of a difference in size
between male and female. Human evolution is driven by the appearance of
increased maternal tester.

Cite your source for this.

 Females gained in size rather than males being
reduced in size during human evolution.
 This is why the male to female size
difference was reduced.

Cite your source.

 According to what I have posted here,

You have posted nothing but a lot of contradictions here.

increased
maternal testosterone increases exposure of the fetal brain to maternal
testosterone, which increases brain androgen receptors.  This increases use
of DHEA by the brain at the expense of body because of competition for
available DHEA.  (If one lives in the cold and gets bigger and moves north,

That is not true, if that were the case, later Neandertals should have
gotten larger,
not smaller throught time.

the competition for DHEA between growth and warmth

Africa was just as warm for chimps/humans as it was for gorillas.
Your
hypothesis makes absolutely no sense at all.

is due to the same
competition.)  So chimps differ from gorillas and orangs in this way.  This
did not occur in gorillas and orangs but together in the common ancestor of
humans.  This is why the chimps did not follow the pattern of gorillas;
chimps' brain compete more for DHEA at the expense of the body.

That is not an answer, just circular reasoning. Can you cite any
worker, other
than yourself, who makes the same claims as you in a peer-reviewed
journal?


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