Human Variation & Race
1. The environmental stress I chose is high altitude. This environmental stress negatively impacts the survival humans, because of its alternating daily extreme climate that often range from hot days to freezing nights and winds are often strong and humidity low, resulting in rapid dehydration. In addition, the air pressure is lower which puts a strain on our bodies.
2. Four ways in which humans have adapted to the stress of high altitude, is:
Short term: Our quick response to high elevation is, an increase in breathing and heart rate, which could as much as double, even while not in motion. Pulse rate and blood pressure go up sharply as our hearts pump harder to get more oxygen to the cells.
2. Four ways in which humans have adapted to the stress of high altitude, is:
Short term: Our quick response to high elevation is, an increase in breathing and heart rate, which could as much as double, even while not in motion. Pulse rate and blood pressure go up sharply as our hearts pump harder to get more oxygen to the cells.
Facultative: An example are the Tibetans, who inhale more air with each breath and breathe more rapidly. Tibetans have better oxygenation at birth, enlarged lung volumes throughout life, and a higher capacity for exercise." Additionally, there is an increase in the oxygen carrying blood cells.
Developmental: There is massive modification in the oxygen transport system of the blood, especially molecular changes in the structure and functions hemoglobin. This adaptation is associated with better developmental patterns such as high birth weight, increased lung volumes, increased breathing, and higher resting metabolism.
Cultural: Usually there is the inability to do normal physical activities, such as climbing a short flight of stairs without fatigue. Some solution we have developed are oxygen tanks or some people take medications to help deal with the dizziness or shortness of breath.
3. The benefits of studying human variation from this perspective across environmental clines, is that we can focus on specific climates and conditions and study those adaptions and then compare them to other conditions. Information from explorations like this can be useful to help us in ways, because we can discover aspects a=that could be used in another way. For example "On returning to sea level after successful acclimatization to high altitude, the body usually has more red blood cells and greater lung expansion capability than needed. Since this provides athletes in endurance sports with a competitive advantage, the U.S. maintains an Olympic training center in the mountains of Colorado. Several other nations also train their athletes at high altitude for this reason. However, the physiological changes that result in increased fitness are short term at low altitude. In a matter of weeks, the body returns to a normal fitness level. "
4. I would use race to understand the variation of the adaptions in #2, by looking at the races that live in high climates, and have for thousands or years, like the Tibetans, Andeans, and Ethiopians. Each of these cultures have adapted in different ways.
The study of environmental influences on adaptions is a better way to understand human variation than by the use of race, because the environment is what leads to adaptions, not race.
Sources:
http://anthro.palomar.edu/adapt/adapt_3.htm
Hey Alexandra,
ReplyDeleteI never thought of that! How the environment leads to adaptations, but race doesn't. I also didn't know that Olympic training for athletes was held in the mountains in Colorado. The more you know! Wouldn't that be a short term adaptation, though? Once the Olympics are over, there's no need for greater lung capacity. That's just how I see it. Although I do see it is a quote, so I suppose I'll have to look that up.
For cultural, isn't that supposed to be something like Americans versus Indians? I would think so, since we have different strategies for adapting than other cultures do. Americans use medication to help out, but some very superstitious people use strange objects to help people when they are sick (I took cultural anthropology over winter).
" In addition, the air pressure is lower which puts a strain on our bodies."
ReplyDeleteSince this is the unique stress of high altitude environments, it needed further explanation. How does lower air pressure impact our homeostasis? What are the negative repercussions?
Good description of your short term trait.
Remember that facultative traits are those acquired by people moving into a new environment and living there long enough to require more than the short term adaptations. So the Tibetan population, that lives in high altitude environments on a permanent basis, would not be a good example of facultative adaptations. They would be an example of developmental adaptations. Increased red blood cell levels (and hemoglobin levels) would be an example of a facultative traits.
Developmental adaptations for high altitude can take several forms. Some populations, such at the Tibetans, actually have lower hemoglobin levels but also have higher respiration levels and larger lung capacities. Andean populations have higher hemoglobin levels and larger lung capacities. Larger lung capacities seems to be one of the most common developmental adaptations to high altitude.
Good cultural discussion.
Good explanation for the benefits of the adaptive approach.
"I would use race to understand the variation of the adaptions in #2, by looking at the races that live in high climates, and have for thousands or years, like the Tibetans, Andeans, and Ethiopians."
But that doesn't explain how race would help us understand that variation? How would it benefit the study? Is it really necessary? How would a biased social construct like race help us objectively understand biological variation? It is okay to say that it has no use for this purpose.