Throughout history, there has always been a type of people like inventors, explorers and people who develop certain theories in a branch of science. How do you explain that?

Answer

Invention has to be seen against the background of the society in which it happens.
There are periods and places where this has happened remarkably often. The Egyptians, who had to lay out the fields in their periodically flooded country, invented geometry. The Chinese invented gunpowder, fireworks and the arch bridge. So inventing is not only given to the nations you list.

Nor is it enough for one person to have an idea: it must be recognized by its environment and provide a “survival advantage” for that environment. For example, the period around the 2nd century BC in Alexandria was particularly fruitful for physics and mathematics; then invention came to a halt until the 12th century in the Islamic empires around the Mediterranean (mathematics, medicine); there it fell silent after two centuries until the renaissance in Western Europe. As this European model was adopted in America, Russia, Japan and now China, it is also invented there. Note that there are a number of great mathematicians and physicists who were born in India, China or Japan, but who could only develop themselves by emigrating to America or Europe. So it’s not just a matter of genetics.

Perhaps read the article in De Standaard from yesterday (15 July) about the connection between IQ and hygiene: that is also a valid point of view.

So your question poses a very complex problem to which there is no simple answer.