WHY SO MANY OF THE VERY OLD SEEM TO BE BLACK
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Date sent:      	Mon, 3 Jan 2000 18:10:37 -0500
From:           	Gregory Cochran


Message text written by Henry Harpending
>


This is a very interesting phenomenon--called the "black-white crossover"
in the literature of demography.  Black mortality rates are higher than
those of whites in the US until about age 70 when the hazard curves cross. 
At age 85 or 90 the annual risk of death is a lot lower for blacks than for
whites.  A good source is a monograph by Manton and Stallard, but I am on
the road and don't have the full reference at hand.


For those amused by political correctness in the social sciences an
interesting sideshow is the extraordinary effort that demographers devote
to explaining the crossover away since, by all they want to believe, it
should not occur.  There is a similar crossover in rates between Han
Chinese and smaller ethnic groups in China.  The description of this, in
DEMOGRAPHY a few years ago, concluded that it must be an artifact (of
course--there are no biological differences between people) of the poor
knowledge of the year system by the ethnics.  No consideration at all to
the different DNA born by different groups.


Henry Harpending

<


     I should read that monograph.  I'd much rather that you were right
about this, since it would be far more interesting than illiteracy-type
explanations. It might be worthwhile listing the ways in which higher black
mortality rates ( male & female) show up.  I need some references for a
complete list, but in this country, cardiovascular disease/hypertension,   
 prostate cancer, and Alzheimer's are among the biggest  These are quite
different from the factors causing shorter black lifespans in Africa






                                  Gregory Cochran