#In many animal species, the blood is red in color. #Until now, little evidence allowed us to imagine the origin of this common trait. #By studying a species of worm, scientists have taken a further step towards solving this riddle.
Thered blood comes from the , a pigment found in the vascular systems of many . The , the , some species of and of produce this hemoglobin. #This common trait can have two origins. #It may be the inheritance of a , or an independent appearance on several occasions.
The, for example, developed in different species independently during evolution, that is, in separate species, a mutation resulted in the creation of what looked more or less like , and these proto-eyes turned out to be practical enough to be selected and endured.
#In the case of hemoglobin, a study – published in– leans more towards the inheritance of a common ancestor. The researchers probed the of #Platynereis dumerilii, a marine annelid whose material slowly evolving. #An asset for scientists today, since it is accepted that the characteristics of this animal are close to those of#Urbilateria : the last common ancestor of most animals! #Scrutinize the of #Platynereis dumerilii is a real leap into the past.
A single gene
#In this case, the analysis of this worm revealed that fiveglobins – some of which make up hemoglobin – were present in #Urbilateria. #Of these five genes, only one code for a globin called “cytoglobin”. #Currently, all circulating hemoglobins in the descendants of#Urbilateria derive from this cytoglobin.
#If so many species present ared, it would be due to this single ancestral gene coding for cytoglobin. #At the by having inherited, that is to say animals with right-left symmetry, it would have improved the transport of oxygen in the blood. These animals, including humans, would only have become bigger and more active.
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#species #red #blood