Interesting data regarding the development of an artery provides further confirmation that human evolution is continuing to act
For a long time the idea has spread that human evolution stopped long ago. But recent research has suggested that genetic change has occurred 100 times faster in the past 5,000 years than in any other period. Now, new Australian research has identified that more and more humans have an artery that normally tends to disappear after birth. This trend, together with other clues, confirms that evolution is continuing to act also in the human being.
An extra arm artery
L’median artery it is a structure used by the fetus to carry blood. Typically this structure disappears about eight weeks after birth to give way to two others called radial and ulnar. The autopsy carried out at the end of the 1800s, they noted that this structure was present only in 10% of adult individuals. The scientists found an increase in the prevalence of this artery in the forearm and hand. Already after the middle of the 20th century this structure started to become more and more present. At the end of the century in some populations the median artery was present in about 30% of individuals. Now, analyzing 78 corpses from around the world, an Australian team of researchers found that this artery is present in about 35% of people. For researchers, this increase would be proof that human evolution is continuing.
Human evolution: not just arteries
For researchers, if this trend continues, most people will have the median artery in the forearm by 2100. The fact that in more and more people there are 3 arteries however, it is not the only proof of human evolution. But this is not the only proof of the action of evolution on man. Researchers point out that more and more people are born without the ability to develop the wisdom tooth. Various researches hypothesize that this may be an adaptation to less chewing and therefore to the spread of smaller and smaller jaws. But not only that: the researchers found that more and more people with the spina bifida occulta, an opening in the sacral canal which is the bone at the base of the spine. In addition, the Australian team also found that many people have extra joints in their feet, even having two or three more bones. Still others are born with the story, a small bone behind the knee that seemed to disappear with evolution. For Professor Maciej Henneberg, of the University of Adelaide:
The median artery is a perfect example of how we are still evolving because people born more recently have a higher prevalence of this artery than humans of previous generations.
It remains to be seen what the genetic factors and the advantages, in evolutionary terms, that drive these changes.
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