Human evolution speeding up? More people born with extra artery in their arm, study shows

ADELAIDE, Australia — Fictional superheroes like the X-Men explore the possibility that humans aren’t done evolving. While no one in the year 2020 has superpowers (that we know of), a study finds many people are being born with evolutionary changes their ancestors didn’t have. Researchers in Australia say more humans today have an extra artery in their arm, which increases their blood supply.

Dr. Teghan Lucas of Flinders University reveals there has been a significant increase in the number of people born with their median artery intact. This artery is the main tube which supplies blood to the human forearm and hand when a baby is first formed in a mother’s womb. Throughout history, this artery typically disappears once two other arteries develop in the arm.

Arm Arteries
A sketch of the median artery vessel which supplies blood to the human forearm and hand. (Credit: Professor Maciej Henneberg)

The radial and ulnar arteries come into existence later in the developing process, with most people 200 years ago living without their median artery. The study finds this trend is now changing and it’s doing so at an incredible pace.

“Since the 18th century, anatomists have been studying the prevalence of this artery in adults and our study shows it’s clearly increasing. The prevalence was around 10% in people born in the mid-1880s compared to 30% in those born in the late 20th century, so that’s a significant increase in a fairly short period of time, when it comes to evolution,” Dr. Lucas says in a university release.

“This increase could have resulted from mutations of genes involved in median artery development or health problems in mothers during pregnancy, or both actually. If this trend continues, a majority of people will have median artery of the forearm by 2100.”

How is this ‘micro evolution’ helping humans?

Study senior author Maciej Henneberg says the reemergence of the median artery is a great sign for the health of the human body. It increases the overall blood supply, especially in a person’s arm. This extra blood channel can also serve as a replacement during surgeries repairing damaged arteries elsewhere in the body.

“This is micro evolution in modern humans and the median artery is a perfect example of how we’re still evolving because people born more recently have a higher prevalence of this artery when compared to humans from previous generations,” the professor from the University of Zurich adds.

“We’ve collected all the data published in anatomical literature and continued to dissect cadavers donated for studies in Adelaide and we found about one third of Australians have the median artery in their forearm and everyone will have it by the end of the century if this process continues.”

Researchers say this isn’t the only sign evolution is continuing in humans. The study points to a growing number of people born without wisdom teeth and born with a fabella, a small bone in the back of the knee joint.

The study appears in the Journal of Anatomy.

Like studies? Follow us on Facebook!