Re: Racial advantages? (from sci.bio.evolution)
James Howard (phis@sprynet.com)
Thu, 08 Aug 1996 14:48:52 GMT
"Bryant" posed some questions to my post: "Re: Racial advantages?
(from sci.bio.evolution)." I want to consider his last question
first. Bryant quotes a little of my message, then asks this: "Are you
suggesting that transcriptional errors are more common during
chimp-development? Do you have any evidence at all for such a
sweeping statement?"
The only reference to chimpanzees in my post is: "Human males and
females have more testosterone than chimpanzee males and females
respectively." I do not consider "transcriptional errors" in any
manner or form. I have to ask Bryant: Where did you get this idea,
and how could you possibly ask me "Do you have any evidence at all for
such a sweeping statement?" Please tell this group where my sweeping
statement, regarding transcriptional errors, is in my post of August
6th.
Bryant quotes me: "Blacks are proven to have more testosterone than
whites. (Orientals are between.)" He wants citations. This may be
found in Table II, page 888 of "5-alpha-reductase Activity and Risk of
Prostate Cancer among Japanese and US White and Black Males," R.K.
Ross, et al., Lancet 1992; 339: 887-889. Testosterone (ng/dl) in
Japanese is 602 (562-645); in whites is 575 (531-622); in blacks is
640 (586-699). Also, consider: "Mean testosterone levels in blacks
were 19% higher than whites [both groups of college students in the
U.S.], and free testosterone levels were 21% higher. Both these
differences were statistically significant." Journal of the National
Cancer Instititue 1986; 76: 45.
Bryant asks: "Do you mean to say that androgen production varies
adaptively across species, reflecting different selection regimes? Or
literally, that testosterone is the main selective pressure in human
evolution?" Yes, I think testosterone is the main selective pressure
in human evolution.
Bryant asks: "Are you aware that testosterone is immunosuppressive?"
My paragraph in my message regarding viral and bacterial infections
definitely says I think testosterone is immunosuppressive. I reviewed
the connection of testosterone and immune responses; there are a lot
of suggestions and findings that testosterone negatively affects the
immune system. I connected these years ago and my work, very briefly
described in my message, gives a precise mechanism of why testosterone
adversely affects the immune system. Testosterone redirects DHEA for
"testosterone target tissues" at the expense of the immune system.
This reduces the amount of DHEA for the immune system and the immune
system is less effective.
I invite Bryant, and anyone interested in this thread, to read my
articles on human evolution and AIDS at
http://www.naples.net/~nfn03605 on the web.
James Howard
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