Australian researchers found that some babies are now being born without wisdom teeth and an extra artery in their forearm, as a result of a human ‘microevolution’ in recent years.
A new study has found that some babies are now being born without wisdom teeth and more people have a previously rare additional artery in their forearm, as a result of a human ‘microevolution’ in recent years. Scientists in Australia have discovered that people are undergoing a micro-evolution in which evolutionary changes can be observed over a short period of time.
Recent research is showing that babies are no longer being born with wisdom teeth, as humans are evolving faster than at any time in the past 250 years. Shorter faces, extra bones in feet and legs, and an artery in the forearm are among a slew of anatomical differences recorded in modern humans. According to the study, the species are experiencing microevolution, where changes take place over a short period of time, after reaching a “relaxed state” of natural selection.
Australian researchers who worked on the paper claim that over time, human faces have gotten shorter, because of which our mouths are getting smaller, with less room for as many teeth. As part of natural selection and our increased ability to chew food, this has resulted in fewer people being born with wisdom teeth.
The new research:
For years, we have all thought that human beings have evolved to their maximum. But researchers have now revealed that human babies are now being born with slightly different features. As part of ‘microevolution’, scientists have found that babies are now being born with a slightly smaller jaw and extra bones in their legs and feet. In addition to this, modern babies have an extra artery in their forearms.
The investigation by Dr. Lucas, along with the University of Adelaide professors Maciej Henneberg and Jaliya Kumaratilake, showed a “significant increase” in the prevalence of the median artery since the late 19th century. The artery forms while a baby is in the womb and is the main vessel that supplies blood to the forearm and hand, but it disappears during gestation and is replaced by the radial and ulnar arteries.
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 scientists believe, “This evolutionary trend will continue in those born 80 years from today, with the median artery becoming common in the human forearm.” The team said their research demonstrates how humans are changing, which they believe it to be microevolution.
Other interesting findings:
Researchers found evidence that humans now have more bones in their feet, while wisdom teeth are becoming obsolete. Most people are born with four wisdom teeth at the back of gums until they push through at adolescence. Anthropologists believe wisdom teeth provided a helpful tool to early humans who used them to eat tough or uncooked foods. But evolutionary changes are making them redundant. This is happening as we have learned to process food more. A lot of people are just being born without wisdom teeth.
Scientists have also seen an increase in people born with a small bone at the back of the knee, the fabella, and extra joints in feet to form abnormal connections between two or more bones. There are also more cases of spina bifida occulta, an opening of the sacral canal, the bone at the base of the spine.
Explaining such evolutionary mutations, Dr. Lucas said, “Humans are currently in a relaxed state of natural selection as our environment is considered favourable to us. We have advanced as a species to the point where natural selection no longer removes the outliers in the gene pool.”
This can be explained with the help of an example of infertile individuals. Natural selection would dictate that they do not have the opportunity to pass on their genes to another generation. However, with the advent of modern tools, and technology and due to modern medicine, they can now reproduce. In this way can we are adopting new tools that are indirectly helping in our evolution.