In the course of evolution some part of the human body became useless, and even began to disappear. A striking example is the bone called fabella, located behind the knee and had very small size. In modern humans it is very rare, so scientists were not even interested in its function — what is known is that she often features in people suffering from osteoarthritis. Over the last hundred years, she, for some reason, began to appear more frequently in the skeletons of people, which begs the question — what is the reason for her return?
The discovery was made by researchers from Imperial College in London, studied the anatomy of humans based on 58 scientific works of scientists from different countries. It turned out that in 1875, this small bone was found in 17% of the people, and by 2018, its prevalence has increased in 3,5 times — found it in the feet in 39% of the inhabitants of the Earth.
It is classified as a sesamoid bone, usually located in the thickness of tendons and adjacent to others. Scientists believe that she, and others like bone, may serve to reduce friction in the joints. At the same time, a huge number of people perfectly well without it, so scientists are wondering — what is it active return?
One of the theories says that its revival may be due to improved diet of modern humans in comparison with inhabitants of previous centuries, modern humans began to eat better, become taller and gained weight. This has caused increased stress on the knees, which some people would raise fabella.
Perhaps, this bone never disappeared — because of its tiny size, the autopsy and x-rays would not be able to detect it. Now researchers have a tomography apparatus that easily detect even the smallest objects.
To understand this question, the researchers intend to collect more data and to divide them by age, location, and other parameters people. According to Professor Michael Berthaume, the bone may really have no important function and cause painful arthritis. If she really is the source of the problem, surgeons will be able to remove it for Troubleshooting.
On the topic parts of the human body that has lost the need for the process of evolution, be sure to check our special material. It lists the body parts that still have many people, but not bringing any benefit.