Discrimination on the basis of color has been going on all over the world for the last hundreds of years. Europeans and Americans consider themselves superior and wiser than Africans and Asians. Today, even though people have started calling racism wrong and generally say that one should look at the nature of a person and not the color of his skin, but somewhere people are still more influenced by the fair complexion. You will be surprised to know that once upon a time, the complexion of all humans in the world was black. Human civilization started with black color only, but today people of different colors are seen in different countries of the world. Even in India, if you see, there is a lot of difference in the skin color of the people of North India and South India.
Human civilization developed in Africa about 2.5 to 3 lakh years ago. Human civilization was born near the Equator and at that time the color of humans was dark black. In fact, the dark color helped them to tolerate the heat of Africa and they used to roam around and hunt comfortably in the harsh sun. Dark color actually helps in protecting the skin from the ultraviolet rays of the sun and the reason for the skin becoming dark is due to a pigment called melanin.
If there is no melanin pigment in the human body and he lives in a region where strong rays of the sun fall throughout the day, then the folate present in his body can get damaged. Cell division takes place in our body due to folate. If folate gets damaged, cell division will not occur properly and body growth will be affected. Along with this, it is very important to have melanin in the body to save folate.
After all, how did the change in skin color occur?
About 1.25 lakh years ago, humans started moving out of Africa. He first headed towards the North West Arabian Peninsula and then towards the Middle East. Migration continued continuously for the next 30 to 40 thousand years. The KIT mutant gene is found in native people of Africa. This gene is protein rich and due to this protein, melanocyte cells are formed in the body, which is responsible for the formation of melanin. Due to migration, this gene reached different corners of the world and at one time people of Europe and Indian subcontinent were also black, but due to difference in geographical location, changes kept happening in the human body and their complexion became fair. .
In fact, the sun's rays do not fall equally on the entire earth. In Africa, Tanzania, Kenya and Boatswain receive maximum sun rays. Whereas Europe is far from the equator and here the nights are longer and colder than the days. Melanin is produced in small quantities in the bodies of the people living here. Ultraviolet rays are not very harmful for these people, because these people do not get much sunlight. Proteins named SLC24A5 and SLC45A2 developed in the bodies of people living in Europe, due to which a decrease in the amount of melanin was also seen. In this way, along with the migration of humans, mutations also kept occurring in genes. About 15,000 years ago humans moved towards America. There is a lot of difference in the temperatures of Africa and America. Like Europeans, Americans also do not need much melanin and hence their skin color also became fairer with time. In Africa and Asia, people used to do farming and animal husbandry since the beginning. These people sweat in the sun all day long, due to which their skin becomes even darker.
Fair skinned people are more at risk from sunlight
For a long time, scientists were unaware of why there is so much variation in human skin. He was clear that there was a geographical factor behind it, but he was unaware of the scientific reason. In the year 1978, America launched a satellite, which was equipped with a Total Ozone Mapping Spectrometer. Through this light, the scientist came to know that along with light and heat, the Sun also emits many types of ultraviolet rays, which are harmful for humans. Excessive exposure to ultraviolet rays can also cause diseases like skin cancer. If a white person stays in the African sun for a long time wearing less clothes, his chances of getting skin related diseases will increase manifold.
The melanin present in the body does not completely absorb the sunlight but also allows some sunlight to enter the body, thereby fulfilling the deficiency of Vitamin D. If people living in cold areas have more melanin then their body will not be able to get the right amount of Vitamin D. Due to geographical location, gene transfer and mutation, so much variation is seen in the skin of people in different countries of the world and this variation is not only in humans but also in animals, birds, fishes and all other creatures. Is visible. Even in trees and plants, changes are seen according to the region.
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