I'd rather like to know how is it that hemoglobin is also found in annelids, echinoderms, some molluscs, some arthropods, etc.
Considering what Dawkins said on this:
The dozen or so different globins inside you are descended from an ancient globin gene which,
in a remote ancestor who lived about half a billion years ago, duplicated, after which both copies stayed in the genome.
‘There were then two copies of it, in different parts of the genome of all descendant animals. One copy was destined to give rise to the alpha cluster (on what would eventually become Chromosome 11 in our genome), the other to the beta cluster (on Chromosome 16)...
‘We should see the same within-genome split if we look at any other mammals, at birds, reptiles, amphibians and bony fish, for our common ancestor with all of them lived less than 500 million years ago. Wherever it has been investigated, this expectation has proved correct
I mean, if it comes from a remote ancestor 500 millions years ago, how come we also find it in yeast and root nodules of beans ? SOmeones got to help me here
I thought of convergent evolution, but can this concept really be stressed out to the point that the eight-helix folded pattern appeared multiple times with time, random mutations and natural selection ? I would love to see the probability of this happening even twice (any statistician out there ?)