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From: duncan@csd4.milw.wisc.edu (Shan D Duncan)
Newsgroups: sci.bio
Subject: Re: Bushmen
Message-ID: <2453@uwmcsd1.UUCP>
Date: Sat, 11-Jul-87 15:23:50 EDT
Article-I.D.: uwmcsd1.2453
Posted: Sat Jul 11 15:23:50 1987
Date-Received: Sun, 12-Jul-87 16:47:09 EDT
References: <4505@ihlpa.ATT.COM>
Sender: daemon@uwmcsd1.UUCP
Reply-To: duncan@csd4.milw.wisc.edu.UUCP (Shan D Duncan)
Organization: University of WI-Milwaukee
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In article <4505@ihlpa.ATT.COM> krista@ihlpa.ATT.COM (K.J.Anderson) writes:

>which claimed that the Bushmen are genetically different from other
>people in the following ways:
>
>a) A camel like hump adapatation, for water storage,
>b) Sterile offspring from marriages to other groups,
>c) Over 50% of the population has number of chromosomes not = 46.
>
>Because I've read several books about anthropology and never heard


[   List several reasons for the low birth rate among
                      the Bushmen (and women :-) )    ]


>
>a) "[Bushmen]...are extremely hardy: the fat on the women's buttocks
>and thighs is a reserve for lean times, 


>
>b) "There is another possible reason why families are small. 
>According to the Bushmen themselves their women are naturally
>sterile during the dry season." [1]  Here again, note that cessation
>of menses is not uncommon among female professional athletes

>ihnp4!ihlpa!krista - I can't help it, I'm just a baby ape.

Add to his points above.  The reason I heard for the cessation of menses
among female athletes is a very low body fat percentage (the estrogens being
STEOIDS and fat soluble... perhaps?).

Bushmen tend to nurse their offspring for what we westerns consider to be a
long time (2-3 years).  In many cases this can act as a form of birth control
(continued elevated oxytocin levels).

Finally humans are not very fertile to start about 30% under the "best"
conditions.  To compare most farm animals are about 80%. This is not unusual
since humans have a relatively long breeding life span and infant care last an
fairly long time.  [ These properties were once refered to as K-selected
atributes... ].

So.  All in all there really is only one species of human alive today 
 using the Biological Species Concept (Actually the Zoological Species
Concept).

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duncan@csd4.wisc.milw.edu |
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