High Altitude- Humans evolved in lower altitudes and when exposed to HIGH altitudes many factors are compromised and result in stress. The body can suffer from hypoxia (Insufficient levels of oxygen in the body tissue), more intense solar radiation, cold temperatures, low humidity, wind, reduced nutritional base, and rough terrain. Hypoxia would be the one that disturbs human homeostasis the most, since it'll affect the heart, lungs and brain. Pregnant woman were affected by preeclampsia (a severe elevation in blood pressure) causing increased infant mortality rates, miscarriages, low birth rates, and premature births. Adaptions-
1. When people born in LOW elevations and travel to HIGH elevations the process of acclimatization begins with in one or two days. This process will increase metabolic rate, respiration, heart rate, and production of red blood cells. With high altitude natives acclimatization occurs during growth and development, they will also have greater lung and heart capacity.
Initial inefficient
response to low oxygen pressure |  |
2. The common solution of Tibetans who live at high altitudes generally has been to breathe faster in order to take in more oxygen and to have broader arteries and capillaries, thereby allowing much higher rates of blood flow and subsequently greater amounts of oxygen delivered to their muscles, despite the fact that they have relatively normal hemoglobin levels. A recent study shows that 90% of Tibetans have a gene called EPAS1, which inhibits the increased production of red blood cells.
3. Glucose burns in a way that permits more efficient oxygen use. This implies the genetic mutation in the mitochondrial DNA, and it also implies that natural selection has acted to increase the frequency of these advantages in these groups.
4. For non natives, rest and less extenuating activities would be best if they are in high altitudes. They will be able to preserve their oxygen levels and won't feel or encounter signs of hypoxia.
Benefits- I believe that the benefits of studying these environmental clines is that it helps science understand the adaption and changes possible by the human body. How the human body adapts to fight or flight situation like Tibetans breathing faster to take in more oxygen and being able to basically maintain a good balance of oxygen in their bodies. Scientist can take this information and gather more and more date as other kinds of populations are exposed to these climate changes/altitudes.
I would use race to classify groups depending on their geological location, not every race is going to live in high altitudes or ever even be exposed to it. You could use race to see how their ancestors adapted million years ago and to understand why a certain race will have a particular gene and another races not have the same gene. It could help us predict how certain races homeostasis will react if an unpredictable climate shift were to ever occur.
Hello Natalie;
ReplyDeleteI found your post to be an interesting read. I find it fascinating to be able to place different races and their ability restrictions depending on where they are located throughout the world. I don't think that people really understand the "whys and hows" when it comes to variations within skin color. I mean to think back when color wasn't a factor. You explained how race could possibly be impacted due to unpredictable climate shifts.
April thomas
Hello, I liked the knowledge you shared with the first question about how humans evolved in lower altitudes. You provided great pictures that represented each topic very well, and your formatting was good as well. Great job!
ReplyDeleteGreat discussion on the impact of high altitude stress, focusing on hypoxia. In particular, I appreciate that you included the risks to pregnant women, as this would definitely impact reproductive success.
ReplyDeleteYou seem to discuss the facultative trait first. Good explanation.
When you talk about your short term adaptaton, you speak of it in terms of Tibetan populations, but Tibetan populations already live in a high altitude environment, so would they need to respond that way? When talking about short term adaptations, you are usually talking about individuals not from that environment and temporarily moving into it. So if we moved from the LA basin up to the mountains of Peru, this is how we would respond until we could acclimate. Does that make sense?
Good discussion on the genetic adaptation for your developmental trait. There are other adaptations as well, such as barrel-chests to allow a larger quantity of air in the lungs with each breath.
Rest and less activity aren't actually cultural adaptations that help you correct the problems with hypoxia. You are just giving in to the impact, not solving the problem. An example of a cultural adaptation would be the use of oxygen tanks for mountain climbers.
I don't disagree that more information and knowledge is beneficial, but how do we actually use this information in a productive way to benefit society? Can the information we gain from these types of studies have medical or scientific implications? Help people with lung diseases, such as cystic fibrosis?
"You could use race to see how their ancestors adapted million years ago and to understand why a certain race will have a particular gene and another races not have the same gene."
But then you aren't using race. There is no genetic basis for the concept of "race" so you can't use race to understand our genetics. Race is not based in biology but is a social construct, based in beliefs and preconceptions, and used only to categorize humans into groups based upon external physical features, much like organizing a box of crayons by color. Race does not *cause* adaptations like environmental stress do, and without that causal relationship, you can't use race to explain adaptations. Race has no explanatory value over human variation.
Hi Natalie~ Your examples are very detailed and interesting regarding high altitudes. Great job!
ReplyDeleteI enjoyed your post, good job. We had all the same points as I too chose to talk about high altitude, however, we did have different views on race being a variation. I don't see how race would be a factor in this because it wouldn't matter when dealing with survival abilities. Great job on everything though!! Very enjoyable! :)
ReplyDeleteThe high altitude adaptation was one of the most interesting to me. Good explanation of what hypoxia is.
ReplyDelete