Due to natural selection, people who lived in areas of intense sunlight developed dark skin colouration to protect against ultraviolet (UV) light, mainly to protect their body from folate depletion. Evolutionary pigmentation of the skin was caused by ultraviolet radiation of the sun.
Since strong sun exposure damages the body, the solution was to evolve skin that was permanently dark so as to protect against the sun's more damaging rays. Melanin, the skin's brown pigment, is a natural sunscreen that protects tropical peoples from the many harmful effects of ultraviolet (UV) rays.
Dark skin. All modern humans share a common ancestor who lived around 200,000 years ago in Africa. Comparisons between known skin pigmentation genes in chimpanzees and modern Africans show that dark skin evolved along with the loss of body hair about 1.2 million years ago and that this common ancestor had dark skin.
These early humans probably had pale skin, much like humans' closest living relative, the chimpanzee, which is white under its fur. Around 1.2 million to 1.8 million years ago, early Homo sapiens evolved dark skin. But evolutionary biologists haven't been convinced that skin cancer itself drove the evolutionary change.
At the outset, then, living near the equator, all humans would have had dark skin. But that's only half the riddle. Why and how did lightly pigmented skin come about?
Elias speculates that, “Once human populations migrated northward, away from the tropical onslaught of UVB, pigment was gradually lost in service of metabolic conservation. The body will not waste precious energy and proteins to make proteins that it no longer needs.”
Studies have suggested that the two genes most associated with lighter skin colour in modern Europeans originated in the Middle East and the Caucasus about 22,000 to 28,000 years ago, and were present in Anatolia by 9,000 years ago, where their carriers became associated with the Neolithic Revolution and the spread of ...
The rarest skin color in the world is believed to be the white from albinism, a genetic mutation that causes a lack of melanin production in the human body. Albinism affects 1 in every 3,000 to 20,000 people. People with albinism usually have very pale or colorless skin, hair, and eyes.
Natives of Buka and Bougainville at the northern Solomon Islands in Melanesia and the Chopi people of Mozambique in the southeast coast of Africa have darker skin than other surrounding populations. The native people of Bougainville, Papua New Guinea, have the darkest skin pigmentation in the world.
Answer and Explanation: The occurrence of white skin results from genetic mutation over the period among people belonging to dark-colored descent. This is an evolutionary change in skin color without causing any selective pressure. Apart from this, white skin spread to different regions through sexual selection.
Until recently, researchers assumed that after human ancestors shed most body hair, sometime before 2 million years ago, they quickly evolved dark skin for protection from skin cancer and other harmful effects of UV radiation.
Modern humans originated in Africa within the past 200,000 years and evolved from their most likely recent common ancestor, Homo erectus, which means 'upright man' in Latin. Homo erectus is an extinct species of human that lived between 1.9 million and 135,000 years ago.
A genetic analysis of an ancient European hunter-gatherer reveals that his face was a striking combination of dark skin and blue eyes.
Indeed, a study earlier this year of ancient DNA suggested that Neanderthals living in what is now Croatia had dark skin and brown hair. “Neanderthal skin colour was probably variable, as might be expected for a large population spread out over a large territorial expanse,” says Harvati.
They found that the known Neandertal genomes had very few SNP alleles associated with light pigmentation in today's people. They suggested that Neandertals had been dark-skinned, brown or red-haired, and brown eyed.
In high-UV environments, darker skin offers protection from the damaging effects of UV radiation, especially to DNA and the valuable nutrient folate. In low-UV environments, there is a trade-off between protection from UV and the need for some UV absorption for the production of vitamin D.
A new study by Missouri School of Journalism researcher Cynthia Frisby found that people perceive a light brown skin tone to be more physically attractive than a pale or dark skin tone.
Natives of Buka and Bougainville at the northern Solomon Islands in Melanesia and the Chopi people of Mozambique in the southeast coast of Africa have darker skin than other surrounding populations. (The native people of Bougainville, Papua New Guinea, have some of the darkest skin pigmentation in the world.)
Nature selects for less melanin when ultraviolet radiation is weak. In such an environment, very dark skin is a disadvantage because it can prevent people from producing enough vitamin D, potentially resulting in rickets disease in children and osteoporosis in adults.
What is the rarest eye color? Green is the rarest eye color in the world, with only 2% of the world's population (and fewer than one out of ten Americans) sporting green peepers, according to the American Academy of Ophthalmology (AAO).
For years, researchers assumed that skin lightened as humans migrated from Africa and the Middle East into Europe, about 40,000 years ago. A sun lower in the sky and shorter day lengths would have favored skin that more easily synthesized vitamin D.
Now you know what is the most common hair colour in the world, but what about the rarest? The rarest natural hair colour is red, which makes up only one to two percent of the global population. You commonly see these hair colours in western and northern areas of Europe, especially Scotland and Ireland.
People living in northern latitudes often don't get enough UV to synthesize vitamin D in their skin so natural selection has favored two genetic solutions to that problem—evolving pale skin that absorbs UV more efficiently or favoring lactose tolerance to be able to digest the sugars and vitamin D naturally found in ...
Broadly speaking, evolution simply means the gradual change in the genetics of a population over time. From that standpoint, human beings are constantly evolving and will continue to do so long as we continue to successfully reproduce.
IT'S NOT JUST YOU, IT'S SCIENCE. Science does back up these sayings. Darker skin can show age more slowly because it has more melanin (dark pigment that determines sun sensitivity).