Todd,
Some questions concerning the blood type/lectin theory.  1.  Doesn't
chimpanzees have the same ABO system as humans, so the evolutionary theory of
Type A, B, and AB happening later come into question?  2.  D'adamo does not
mention anything concerning celiac disease in his book (at least from my quick
overview), and is that not suspected of causing autoimmune disorders due to
gluten (foreign protein) assimilation?  Which also brings to question the
blood type groups that he says are immune to wheat and the other grains that
contain gluten,  who have celiac responses?  3.  Has there been a survey to
identify any hunter/gatherer groups that have any blood types other than Type
O?
I know these questions are probably very rudimentary, but these would help
clarify issues concerning the paleo lifestyle for alot of us who don't have on
hand expertise materiel.
Thanks for your consideration,
Ella