There are more and more children entering the world without their wisdom teeth, and scientists think micro-evolution is behind it.
It seems that more babies are entering the world without their wisdom teeth as scientists claim human evolution continues to change our physiology faster over shorter periods, according to a new study. According to a report published in the Journal of Anatomy, humanity is currently undergoing a micro-evolution that's causing evolutionary changes in our biology much faster than at any other point within the previous 250 years. Researchers with the Flinders University in Adelaide, Australia, discovered that more and more modern babies are born with smaller jaws and shorter faces, which means they have less room for the typical number of teeth.
"This is happening in time as we have learnt to use fire and process foods more,” said Dr. Teghan Lucas, who co-led the study.“A lot of people are just being born without wisdom teeth.”
Our wisdom teeth are the third molars in the human mouth and consist of four wide and tough teeth located toward the back of our jaws. It's common for these teeth to be surgically removed as when people get older. Some of the reasons for surgery are if the teeth fully erupt or don't grow healthily. For instance, they can become hidden under gums or even crowd other molars resulting in damage to nearby teeth.
Lucas, along with his university colleagues, professors Jaliya Kumaratilake and Maciej Henneberg, also learned that some are born with extra bones in their legs and arms and bizarre connections between two or more bones in their feet.
These researchers also discovered that there'd been a big increase in the existence of a median artery every since the beginning of the 20th century. This artery forms while children are still in the womb, and it is the primary vessel that supplies blood to a person's hand and forearm. However, during gestation, the artery is typically replaced by the ulnar and radial arteries, which then become the two primary arteries.
"But increasing numbers of cases retain it, so a person can have all three arteries,” the study noted.“This evolutionary trend will continue in those born 80 years from today, with the median artery becoming common in the human forearm.”
This study's eye-opening results show how fluid human evolution can be and how fast it can take place. 3
"This is ‘micro evolution’ in modern humans,” Henneburg commented.“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 when compared to humans from previous generations.”
The study was conducted using the tracking rates of retention related to different human body parts throughout generations and by dissection of preserved human corpses born within the 20th century.
"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,” Henneburg added.
The researchers believe that changes in natural selection might explain the current micro-evolution taking place.
"A lot of people thought humans have stopped evolving,” Lucas said.“But our study shows we are still evolving – faster than at any point in the past 250 years.”
As the planet undergoes more and more dramatic changes due to climate change, one has to wonder how it could affect human evolution in the short and long-term.