So what light does this shed on human origins? Is it possible for the two people of the Creation account (Adam and Eve) or the eight people on Noah's Ark to give rise to all of the ABO blood types present in humans today? If Adam and Eve were heterozygous for blood types A and B, respectively (one allele for type O and one allele for either type A or B), they could have produced children that had any of the ABO blood types, as illustrated in Figure 2. The Punnett square simply predicts what the possible phenotypes would be for a given couple's children. From the number of children that Adam and Eve likely produced, it is not difficult to envision all of the ABO blood types being passed down to their offspring.