Blood Type Variations

name        Neil
status       student
grade        9-12
location     ND

Question -   Hi,
I was just wondering what the evolutionary perspective on blood types
is.  How did they come to form?  Also, why are there variations if there
are not apparent selections against a certain type?
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Dear Neil,

Another student asked a very similar question about Blood Type Proteins,
although not quite as in depth as yours. But the excellent replies from 2 of
our scientists might also provide some insight into your questions:

http://www.newton.dep.anl.gov/askasci/mole00/mole00594.htm

My apologies for the delay in replying,
Jeff Buzby, Ph.D.
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