Race Post

1.               Select only ONE of the following environmental stresses: (a) heat, (b) high levels of solar radiation, (c) cold, or (d) high altitude. Discuss specifically how this environmental stress negatively impacts the survival of humans by disturbing homeostasis.

Since humans are not subarctic animals adapting to cold is difficult. We do not grow dense fur coats nor do we usually have thick layers of fat insulation like polar bears. 

When we are cold we may experience any one or all of the following negative impacts:

1.     Goose pimples due to the lack of hair that helps improve insulation.

2.     Red cheeks due to dilated blood vessels while the body tries not to lose heat.

3.     Shivering in an attempt to generate heat and help keep warm.

4.     Difficulty maneuvering fingers as touch and sensitivity and precision as the nerve cell that transmit these impulses and muscles controlling actions work slowly in cold.

Although the above have happened to most people over time, the extreme and prolong cold can lead to:

5.     Frost-nip, when the skin loses color and sensation.

6.     Frost-bite, affecting the deep layers of muscle and bone. This is permanent tissue damage and results in amputation of fingers, toes, feet, hands etc…

7.     Hypothermia, life threatening drop in the core body temperature.

2.               Identify 4 ways in which humans have adapted to this stress, choosing one specific adaptation from each of the different types of adaptations listed above (short term, facultative, developmental and cultural). Include images of the adaptations.

Humans have adapted to this environmental stress by:
Shivering is a tactic, in which our muscles contract and expand in speedy bursts. This exercise produces heat, which helps to raise body temperature.
Vasoconstriction when the body minimizes heat loss which is more energy efficient. Vasoconstriction restricts capillary blood flow to the surface of the skin, which reducing heat loss at the body surface. This preserves core body heat by reducing peripheral blood flow. 

Body build and structure such as a stocky body with short appendages would be more efficient at maintaining body heat because it would have relatively less surface area compared to body mass.The fat layer provides insulation throughout the body.

Lastly as a cultural adaptation is the use of insulating clothing, houses, and fires.

3.               What are the benefits of studying human variation from this perspective across environmental clines? Can information from explorations like this be useful to help us in any way? Offer one example of how this information can be used in a productive way.

Human health, energy, and comfort are affected more by climate than by any other element of the physical environment. Aside of better understanding ourselves.

The benefits of studying human variation can clear the controversy of superior and inferior race. This can also aid in the misconceptions such as when naturalist Louis Agassiz asserted that whites had bigger brains than others, and promptly concluded that they must therefore be more intelligent. It may also help the prevention of cultural diseases such as TB, HIV/AIDS, small pox, swine flu to name a few and aid in vaccinations. The development of medical practices that can alleviate the suffering associated with human disease would be very productive.

4.               How would you use race to understand the variation of the adaptations you listed in #2? Explain why the study of environmental influences on adaptations is a better way to understand human variation than by the use of race.

I don’t think race can be used to understand the variation of the adaptations I listed in question #2 because it does not influence how well our bodies adapt to cold climates.  Environmental influences provide stronger evidence of the successful adaptations of human environments. Adaptation to cold climate is dependent on our body’s ability to reduce heat loss and to increase internal heat production. The ability to adapt and change is existent in the all humans so this connects us more genetically than the color of our skin, hair or eyes. It forces us to see that these external differences are a result of our environment. We are all Homo sapiens.