What factors caused the correlation between the reduction in skin pigmentation in humans and migration of human populations away from the equator?
A. The exposure of human populations to less UV light required a reduction in melanin to produce more vitamin D for healthier bones.
B. The exposure of human populations to new sources of food common to the polar regions caused changes in physiology that resulted in the production of less melanin.
C. The exposure of human populations to predators only common to the polar regions caused them to adapt by camouflaging better with the environment.
D. The exposure of human populations to new diseases common to the polar regions interferred with melanin production causing lighter skin.
A. The exposure of human populations to less UV light required a reduction in melanin to produce more vitamin D for healthier bones.
U sure
Yes, I'm sure. The reduction in melanin in human populations is primarily caused by the need to produce vitamin D in regions with less UV light, as melanin can inhibit the production of vitamin D. This adaptation allowed human populations to survive in regions with less UV light, such as further away from the equator, where there is less intense sunlight. This is supported by scientific research and evolutionary theories.
The correct answer is A. The exposure of human populations to less UV light required a reduction in melanin to produce more vitamin D for healthier bones.
To understand why this is the case, we can look at the role of melanin and UV light in human skin. Melanin is the pigment responsible for the color of our skin, hair, and eyes. It acts as a natural sunscreen, protecting the body from harmful UV radiation.
When humans migrated away from the equator and settled in regions with less intense sunlight, they were exposed to reduced levels of UV light. But UV light is crucial for the synthesis of vitamin D in the body. Vitamin D plays a vital role in the absorption of calcium for bone health.
In regions closer to the equator, where UV radiation is more intense, higher levels of melanin are advantageous. Melanin absorbs and scatters UV light, reducing its harmful effects and protecting the body from conditions like sunburn and skin cancer.
However, in regions farther from the equator, where UV light is less intense, the body needs more exposure to UV light to synthesize adequate levels of vitamin D. As a result, human populations in these regions evolved to have reduced melanin production. This allowed for increased penetration of UV light and, consequently, more efficient synthesis of vitamin D.
The reduction in melanin production over successive generations led to the lighter skin tones often seen in populations that migrated away from the equator. So, the correlation between the reduction in skin pigmentation and the migration of human populations away from the equator is primarily due to the need for increased vitamin D production in regions with lower UV light exposure.