Human Variation and Race

     Heat can greatly impact the homeostasis of humans.  Although it is well known that humans deal with heat much better than they do with cold,  there can be great consequences with too much exposures to heat.  Humans who are exposed to heat run a really high risk of dehydration.  The body however does have it's mechanisms to deal with this.  Heat can impact where humans live, what they eat and what they do.  These things are some of the basic necessities of life and any imbalance can have a huge detriment in their lives.

     Short term adaptation

          An example of a short term adaptation with heat acting as an environmental stress would the the bodies ability to sweat.  This is a way a body reacts to heat as a cooling mechanism.  However as the body reacts by sweating to cool itslelf off it begins to lose plenty of fluids.  Humans need to make sure to stay very well hydrated to replenish any fluids that it loses because of its ability to sweat.

     Facultative adaptation 

          Vasodilation is a form of facultative adaptation.  This is when blood vessels expand in the skin to increase blood flow to it.  With vasodilation the body's inner heat is radiated outward towards the skin as mean to cool itself off.

     Developmental adaptation

          Human populations who are exposed to heat regularly have seen a decrease in body hair.  This change in the body allows for enhanced cooling effects for the body.  This is something that has devoloped throughout the human species.  This is also considered an evolutionary adaptation.

     Cultural adaptation

          As a culture we find ways to adapt to different things.  We found ways of cooling ourselves by developing technologies that aid us in doing so.  Air conditioning systems can be found at our work, homes and in our vehicles. We have developed clothing fabrics that protect us from the heat and cool us off at the same time.  This has made it possible for us to live in almost any type of environment. 


     Studying this information across these environmental clines helps us better understand how humans react to stresses in the environment.   By understanding each step one has a better understanding of how these stresses affect them.  We understand more of how are bodies are adapting to these stresses and we can come up with new ideas on how to understand and build more resources to help us adapt to our changing environment.   An example of this would be using fluids and different equipment to hydrate us.  As a culture we have come to learn where to push our bodies to the limits for physical gains.  Now we understand more of what is needed in fluids to keep us hydrated to help us achieve this.  We now include electrolytes to help us in replenishing our fluids.

     It would be very difficult for me to use race to understand the variation of the adaptations I listed earlier.  I think that the study of environmental influences on adaptations is a better way to understand variation than by the use of race.  After all it is the environmental influences that I believe create these races in the first place.  I believe since populations exist all over the world these races themselves have found a better understanding of their own people by studying these environmental influences.