Where did the different blood types come from?

Question

Where did the different blood types come from?

Answer 1

nobody really knows. its like where did the different hair types come from. but they all have their different characteristics

im a type O. and because of that i should be eating more meat that anything else in my diet. other blood types respond better to other types of food as well.

it might have been because of the way we eat and the way our blood responded to the changes in diet and humans changed locations around the world.

good question

Answer 2

It is known that the different blood types (A, B, O, and the Rh factor) are also present in other primates. In fact the Rh factor was first discovered in Rhesus monkeys. It is yet unknown exactly how these proteins evolved but judging from their function (they are marker proteins on the surfaces of red blood cells) it would appear that there may have been originally one blood protein, A, and perhaps a mutation in subsequent offspring resulted in the creating of a second similar protein, B. Because blood type does not in anyway enhance one's darwinian fitness, (except during childbirth - Rh disease) there was not much positive nor negative selection for these blood proteins and thus the ratio of blood cells today may have been mainly a result of probability due to balancing selection.

The appearance and subsequent modifications of these blood type proteins may resemble the evolution of hemoglobin (originally there was one hemoglobin protein, now there are 13 total in humans (7 alpha globin, and 6 beta globin) all of which bind oxygen, but with slightly different affinities. However there may have been more pressured selection for the globin genes, as they are more essential to life than the blood surface proteins.