Evolution of Human Hair
Human hair has undergone various changes throughout the course of evolution. Some of the most significant changes include:
Reduction in body hair
Humans have significantly less body hair than our primate ancestors. This reduction in body hair is believed to have occurred as we evolved to become bipedal. As our bodies more exposed to the sun’s heat, having less hair availed us to dissipate heat more efficiently.
Hair texture
The texture of human hair is highly variable, with different accumulations exhibiting different hair types. This variation is believed to be due to a combination of genetic and environmental factors.
Hair color
Human hair color varies widely with shades ranging from blonde to black. The evolution of hair color is believed to be linked to the presence of vitamin D. Pale skin & light hair are thought to have evolved, in response to lower levels of vitamin D in areas with less sunlight.
Hair growth patterns
The growth patterns of human hair have also undergone many changes over time. For ex. the hair on our heads grows much longer than the hair on other parts of our body, such as our arms and legs.
Pubic hair
Humans are unique among primates in having hair in the pubic region. This hair is believed to have evolved as a form of protection against friction during sexual intercourse.
Beard growth
In males, the ability to grow a beard is a supplemental sexual characteristic that is linked to the hormone testosterone. While some populations have a higher incidence of beard growth than others population, it is believed that the ability to grow a beard evolved as a form of signaling dominance and masculinity.
Eyebrows
While all primates have hair above their eyes, human eyebrows are uniquely shaped and positioned. It is thought that the evolution of eyebrows allowed for more effective communication through facial expressions.
Hair loss
While humans have evolved to have less body hair we are also prone to hair loss on the scalp as we age. It is believed to be linked to hormonal changes & genetic factors, and it is not clear why this trait has evolved.
In summary, the evolution of human hair has been shaped by a variety of factors, including environmental pressures, sexual selection & genetic variation. These changes have contributed to the wide range of hair types, textures, and colors seen in modern humans.
Hair is full of surprising facts click here to know more
Interesting and lesser-known facts about human hair click here to know more