People also inherit mental illnesses from their ancestors!

Not only intelligence but also mental problems are genetically inherited from primitive ancestors. The human brain has evolved over millions of years. There have also been changes in the gene sequence. A recent study shows that genes related to mental problems appeared about 475,000 years ago. No evidence of the existence of modern humans (Homo sapiens) has been found in that ancient period.

The oldest evidence of modern humans is found in Morocco, Africa. The fossil found there is estimated to be about three hundred thousand years old. It is not known whether modern humans existed before that. It is assumed that modern humans appeared on earth from that time. Before that (about seven to two hundred thousand years ago), the ancient human species Homo heiselbergensis roamed the earth. Although there is no evidence that modern humans evolved directly from them. Recent research results indicate that genes related to mental problems existed on earth even before the emergence of modern humans.

There are different opinions about who the closest ancestors of humans are. However, according to the prevailing opinions, the living ancestors of humans include chimpanzees and bonobo monkeys (their physical structure is slightly different from that of ordinary chimpanzees). Human genes are largely similar to these two animals (about 98 percent). Human evolution began approximately 5 million years ago by separating from chimpanzees and bonobos. Since then, the size of the human brain has increased by about three times.

Fossils of primitive humans provide an idea of ​​the size of their brains. But fossils cannot provide much information about what their brains were capable of doing at that time. For this information, research on the human body's genes is required. Recently, several studies have shown that along with the human gene sequence, there have been changes in intelligence, brain size, and height. Even genetic sequences have been associated with various types of diseases.

Ilan Libedinsky, a researcher at the Center for Neurogenomics and Cognitive Research in Amsterdam, Netherlands, conducted research on these two fields together. In it, Libedinsky and his colleagues found that genes related to human intelligence appeared about 500,000 years ago. After that, some genes that are currently associated with mental problems also appeared. Libedinsky said that the study suggests that both intelligence and mental illness appeared in humans along with the evolution of the brain and genes.

For this information, researchers tried to find the original source of the 33,000 different genes found in modern humans. It was found that those genes appeared between the last 3 million and 4,000 years. Relatively new genes appeared in the last 60,000 years. In fact, it is believed that Homo sapiens left Africa and spread to other continents during that time.

Researchers have also created a 'timeline' of which genes appeared at which time. For example, genes related to digestive disorders appeared about 800,000 years ago. The genome-related issues that are currently associated with cancer appeared approximately 590,000 years ago. Genes related to mental problems were not seen at this time.

After this, genes related to advanced human intelligence appeared. For example, genes related to the ability to solve problems logically in a new situation. They evolved about 500,000 years ago. The study also found that genes related to mental health problems appeared shortly after genes related to intelligence. These genes appeared about 475,000 years ago. Much later, over the past 50,000 years, genes related to language evolved. Even later, genes related to alcoholism and depression appeared in humans.