Human Variation and Race

1)      Heat negatively impacts human’s survival because it causes the body to rise to dangerous temperatures. This can result in dehydration, heat syncope (fainting), heat exhaustion, and heat strokes, which can potentially cause damage to the brain or death.

    2)      Short term adaption- Sweat is a short term form of human adaptation towards heat. The human body produces sweat as a way of cooling itself down.  Studies have shown that it is easier for populations to withstand the dry heat of the dessert better than the humidity from the tropical areas. This is because the sweat we produce is easily evaporated, providing us with a quick cooling sensation, while in humid areas sweat cannot evaporate quick enough.

Facultative adaptation- An example of facultative adaptation to heat is peripheral vasodilation. This involves the dilation of blood vessels in the skin, bringing large quantities of warm blood from deep within the body closer to the skin. This is what causes your skin to become red or flushed when you are hot. The heat that was brought closer to the skin can then be removed by radiation or convection.

Developmental adaptation- One developmental adaptation humans have grown into through the help of numerous generations is bipedalism. Although this is currently just an unproven theory, it is still a possibility that we have adapted to heat overtime. Many scientists believe that our early ancestors evolved from being quadrupedal to bipedal to escape the heat that is closer to the ground. Our ancestors could have also stood on 2 feet in order to avoid the direct sunlight that would normally hit them if they were on all fours. This could also have been the reason for our tremendous loss of body hair overtime.

Cultural adaptation- Humans have relied on the use of air conditioners of over one hundred years. We use this as a mechanism to cool the body and avoid dangerously high body temperatures.

3)      One benefit of studying human variations through environmental clines is the ability to observe humans beyond race and ethnicity. Yes, information from explorations can be useful because the can provide us with ways to overcome the heat stresses. Scientists can observe how people living in hot environments deal with the heat. They can then bring this information back and use these methods to help people that are suffering from heat exhaustion in other parts of the world.

4)      The study of environmental influences on adaptations is a better way to understand human variation than by the use of race because we are all human. In my opinion, you cannot use race to understand the adaptations human have made to deal with heat. Heat affects every race, and there is no one race that was born with the ability to withstand high temperatures better than others.