THE RACIAL EVOLUTION

Adolf Hitler once described African American athlete Jesse Owens as among “people whose antecedents came from the jungle…primitive…and their physiques were stronger than those of civilized whites …hence should be excluded from future (Olympics) games”.

This is just one example of racial prejudice, a vice that have afflicted the human society for centuries with Africans being the biggest victims due to their uniquely dark skin. European colonialists in the 1600s are said to have referred to African women as “the sexy part of the bible” in a bid to justify their sexual exploitation during the transatlantic slave trade that claimed more than 15 million lives.

Racism against African people was further reinforced by the fact that in popular culture black is associated with everything evil while good is denoted in white. Angels and heaven are depicted as being brightly coloured while the devil and his kingdom are portrayed as tailed black beings.

However, recent scientific findings have shuttered these prejudices with the findings indicating that until 100,000 years ago all human beings were black. According to this theory, Europeans and Asians lost the dark pigmentation after the great “Out of Africa” emigration, a period of huge human exodus from Africa to other parts of the world.

“The migration of humans from the region of origin which is East Africa to other parts of the world is the course of the diverse skin complexions that grace the world today,” explained Dr. Nina Jablonski, a professor of biological anthropology at Pennsylvania University in the USA and expert in the evolution of the human skin. “This emigration was not rapid but it was a gradual process through time as our ancestors sought food and other social and physical needs in distant lands”.

Dr. Jablonski was in the country a few weeks ago where she delivered a talk at the National Museums of Kenya explaining scientifically why there are skin colour variations not only among people of different continents but also regions and countries.

According to supporters of the Darwinian theory of the origin of mankind, skin colour is the most visible product and evidence that modern man developed through several stages of evolution. This skin colour evolvement, experts say, was in tandem with the loss of excessive bodily hair to enhance the cooling mechanism. Unlike humans, apes usually have a problem in cooling due to their natural fur coat. Mammal brains are particularly venerable to the heat with a change of five or six degrees being able to induce a heatstroke.

“Due to their skin being covered by far chimpanzees, gorillas and other primates have a big problem in keeping cool given the fact that they lose heat by sweating,” the American scholar explains. “In the evolution process humans, with a bigger brains, lost their bodily hair which drastically increased the surface area for heat regulation through evaporation ”.

This, scientists say, happened between 4.5 million and two million years ago when early humans moved from the rain forests to the East African savanna where they had to cope with exposure to the sun as they hunted and gathered. Rapid dispensation of heat through sweating was nature’s easiest way of dealing with this new challenge.

“The more they could sweat, the longer they could forage before the heat forced them back into the shade,” explains Gina Kirchweger in the American scientific journal Discover. “The more they could forage, the better their chances of having healthy offspring and of passing on their sweat glands to future generations”.

Today an average human being has an average of two million sweat glands spread across the entire body which explain why he is one of the most ventilated overland creatures.

The exposed skin is said to have grown darker as the underlying tissues tried to form a barrier against the destructive tendencies of Ultraviolet B (UV-B) radiation. During the homo erectus era, around 1.2 million years ago, ancestors of modern man had the skin characteristics of Africans which are dominated by melanin-induced dark pigmentation.

Scientists say that all human beings remained black for 1.1 million years until the scenario changed between 70,000 and 100,000 years ago when the dark skinned humans started migrating to the low UV zones in the northern hemisphere. The less intense sunlight and cold climates led to the development of heavy clothing which means the skin was more often than not covered, said to be one of the factors leading to the development of light skin complexions among the native inhabitants of Europe, Asia and the Americas.

According to one scientific text, “as population began to migrate, the evolutionary constraint keeping skin dark decreased proportionally to the distance North a population migrated…and as northern populations experienced positive selection for lighter skin due to the increased production of Vitamin D from sunlight the genes for darker skin disappeared from these populations”.

After the so-called “Out of Africa” migration scientists claim that the lighter skin complexions might have also been accelerated by diet. As food sources rich in Vitamin D like game meat, fish and some plants dwindled the skin colour lightened to enhance the production of high volumes of the vital vitamin from a limited solar source.

Africans and other dark skinned people, with layers of melanin blocking the absorption of UV rays have a limited ability to synthesis Vitamin D from their skin. For this reasons some scientists have concluded that African Americans and other dark skinned people living in low UV zones like Europe and America are disadvantaged vitamin D-wise hence have to use supplements and food sources. However, some scientific studies have disputed these claims saying the hindrance caused by melanin is minimal.

On the other hand when light skinned Europeans and Americans travel to Africa they need to apply layers of sunscreen when lying in sunny beaches since exposure to the intensive tropical sun rays can lead to skin damage and ailments like skin cancer. Under exposure to equal intensities of sunshine, light skinned people are ten times likely to die from skin cancer than dark skinned people. 

“People of colour have more protective natural sunscreen in the form of melanin in their skin, hence it takes a longer time for them to make vitamin D from available sunlight,” the American scientist explains. “If they live in low UV areas and stay indoors most of the time, it is even more of a potential liability because they have almost no chance to make vitamin D in their skin”.

Among many furred animals hair is used to express emotions like anger and fear. But during the evolution process, Dr. Jablonski claims, human beings developed numerous facial muscles through which they could easily express their moods hence excessive bodily hair was no longer needed. The only thick coat of hair spared was that on the scalp which is supposed to control the cooling of the brain.

“And since colours have evolved independently of other human traits all human beings are the same under the skin, which makes classification of races according to skin colour biologically nonsensical,” she notes.

During the preparation for a lecture in Australia ten years ago Dr. Jablonski stumbled on a study that examined the effects of UV rays on folate, a member of the vitamin complex. The study indicated that when light skinned people are exposed to the sun for an hour they might lose up to half the body’s folate which can lead to various complications to the individual or his offspring.

The dark skin among people in hot areas like Africa might have developed as nature’s way of protecting the loss of the vital folate from the body. Therefore, according to the American skin colour evolution expert, vitamins and exposure to the UV rays are the two principle reasons why the world is home to diverse races.

“The understanding of the evolutionary basis of skin pigmentation, and particularly appreciation of the fact that the same kinds of dark and light pigmentation have evolved many times in human history is very important for fighting racism,” Dr. Jablonski explains. “Many racists beliefs sprang from erroneous notions that colour was essentially to moral character and that dark pigmentation was similar to that of the devil and demonic forces, while light pigmentation was associated with the white luminance of God”.

She goes on to say that skin colour evolution knowledge will expose such theories as damaging falsehoods and help the world understand that skin pigmentation is not in any way related to traits like intelligence or behaviour.

“In other words, understanding the biology behind skin colour lays bare the blatant falsehoods underpinning much of the racists’ ideology,” Dr. Jablonski concludes. 

 WHY ARE AFRICANS BLACK?

Melanin, produced by cells known as melanocytes, is a substance that gives the skin its colour and acts as a natural sunscreen against destructive solar rays. The more melanin there is in the skin the darker the complexion and vice versa. Excessive solar radiation causes DNA damage to the skin against which the body reacts by releasing more melanin, which darkens the complexion. This explains the dark skin among populations in Africa and other tropical regions and why some Europeans acquire a tan when exposed to the sun.

Similar skin colours are said to have evolved independently multiple times under similar environmental conditions which explains why although African people are black, the shades of their skins vary greatly across the continent. There are those like South Sudanese who are jet black while others like the Southern Africa Bushmen and Ethiopians are light skinned.

Scientific says that skin colour variation, the difference between the lightest and the darkest shades, is highest in sub-Saharan African populations with reflectance values ranging from 19 to 46 compared to those in Europe and East Asia at 62 to 69 and 50 to 59 respectively.

Prejudice and popular culture mostly spread by Western media has reinforced the fallacy that the beauty of a woman is defined by the colour of her skin, and most often than not the lighter the complexion the better. In Europe before the Industrial Revolution pale skin was preferred since it was a sign of high-class people who spent most of their time indoors. Tanned skin was a trait of lower labourer class who spent the better part of the day toiling under the sun.

But today Western culture glorifies tanned skin as a symbol of holidaying in exotic destinations, sportiness and good health that comes with wealth and higher social status. Many credit this turn around to the trendsetting French fashion designer Coco Chanel, founder of the famous fashion label Chanel, for making tanned skin look cool in her publicity adverts in the 20s and 30s.

Colonization brought in a prejudice against everything African from culture, language, religion and skin. In a quest to look like their masters’ wives and daughters dark skinned African women would use bleaching agents to lighten their skins and hands. Although the trend have slowed down in recent years as many purport to adhere to the creed of “black is beautiful”, light skinned females are still worshipped in society today, proved by the fact that most winning models, popular presenters and other female pacesetters in African countries are of light complexion.

However, long before the coming of Europeans to Africa light skinned women were idolized among some communities. Research has also established that even in the African American community light skinned women score high among men than their dark skinned counterparts. The same thing applies in Asian countries like Japan, India, South Korea and Vietnam where being pale associated with high social standing since ancient times.

For these reasons, skin whitening products sales across the world grew from $43 billion in 2008 to more than $90 billion in 2010.