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If we decended from apes how do we explain RH Negative blood?

As someone who is still learning everything I can to answer my questions on where we come from I recently learned that my blood type does not descend from the rhesus monkey. I have come to realise that God most likely doesn’t exist and that we evolved from apes but how do you explain where people like me with RH Negative blood come from. I have yet to find an answer to this question and was hoping I could find it here. Unless of course what I read was incorrect.

Posted: June 11th 2008

Maxx Power www

I think an underlying principal of evolution at work here is the idea of common ancestry. When we say we are biologically related to Chimpanzees and Rhesus Macaque, we don’t mean we came directly from them. While it is true we do share a large amount of our DNA with both species, we are a completely different species which diverged off from another organism, what is known as a common ancestor. This is a pre-Holocene Ape, long since extinct, that was the direct ancestor of all the Apes we see today.

If it were the case that we descended from modern-day Rhesus Macaque’s then there would be an issue. But we diverged from the same ancestor many millions of years ago. During that divergence different pressures of natural selection would have been present on us in comparison to other species. It’s therefore feasible to suggest that while Rhesus Macaque species lost the need, or rather the genes, for Rhesus Negative blood types, we in comparison either had a need to keep this type of blood group, or we simply didn’t detrimentally suffer from having it and it therefore became a benign mutation that caused no harm.

Posted: June 14th 2008

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SmartLX www

I don’t know whether it’s true either, but it’s certainly plausible that all Rhesus monkeys are positive. It’s not a question of where Rh negative blood in humans came from, but where it went in the monkeys.

The Rhesus blood group system is named after the Rhesus macaque, but not because the macaques themselves have the same system of positives and negatives as you might assume. It’s because when a rabbit is immunised with red blood cells from a macaque, it exhibits characteristics of an Rh positive. The macaques might be universally positive, but the rabbits aren’t. This was the experiment that kicked off the whole area of research.

The Rhesus factor is one pair of genes which determines whether you produce a certain antibody generator, or antigen. We determine whether blood is positive by checking for the resulting antibodies. But here’s the important part: Rh positive is a dominant gene, and Rh negative is a recessive gene.

That means that if either parent carries the positive gene, the odds are on positive for the child. Rh negative, like red hair, is slowly dying out through the free interbreeding of those who have it and those who don’t.

Assuming it’s true that there are no Rh negative Rhesus macaques, this simply means that the negative gene has already died out among their population. Negative blood didn’t evolve from nowhere, it’s just fighting a losing battle throughout the animal kingdom. Humans are one of its remaining strongholds.

Posted: June 13th 2008

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