Oxygen is one of the essential elements
for human survival. The environmental stress of high altitude impacts human
survival, which disturbs homeostasis due to the lower air pressure in those regions.
Pressure in high altitudes are much less when compared to pressure at sea
level. When one is at sea level, oxygen enters much easier through lungs, making
their way to vascular systems (blood streams). At high elevations, oxygen doesn’t
enter our lungs as easily, which means one gets less of it in their blood stream.
This high-elevation condition is called hypoxia, also known as oxygen
deprivation. Hypoxia defuses physical activities, and some of the symptoms
include; headache, fatigue, lack of appetite, vomiting, distorted vision, and
difficulty with memorizing and thinking clearly. In some cases, symptoms could
be more serious; developing pneumonia-like symptoms and accumulation of fluid
around the brain. These pulmonary and cerebral complications are usually deadly
if there is no return normal air pressures. Furthermore, the added stress on
the lungs, heart and arteries increases the risk of heart failure (Palomar).
Humans in high altitudes could
adapt to these higher regions in four ways; short-term adaptation, facultative
adaptation, developmental adaptations, and cultural adaptation.
Hiking a mountain is a short-term adaptation. The goal is to
climb on a mountain – reaching high elevation – and returning down to the
original elevation. The human body responds quickly to this type of change in
environment. Since the atmospheric pressure is less in elevated regions, it becomes
difficult for some to breath, which causes physical inability to move at a normal
pace. It is a temporary response of the body, until it returns to the original-lowered
elevation.
If one were to visit the country of Bolivia, they would be
faced with a considerable environmental stress of nearly 17,000 feet above sea
level. The facultative adaptation would consist of the body responding to a prolonged
stress of adjusting to the extreme climate. This process is called acclimatization;
where red blood cells and capillaries are produced to carry more oxygen, and the
lungs increase in size to facilitate the osmosis oxygen and carbon dioxide
(Palomar). The increase of red blood cells are phenotypic expressions of the human
genes that turn on and off as a response to such environmental stress. Acclimatization
is a slow process, but never reaches the mental and physical fitness from its
original lower altitudes. Acclimatization is fully successful, when one returns
home – t o their original elevation.
Developmental adaptation are traits found in the DNA of people.
Let’s continue to consider the people of Bolivia, who live in an estimated
elevation of 17,000 feet above sea level. They are a population more successful
in adjusting to long-term environmental stresses of high elevations. The reason
they have adapted to such climate, is due to their long ancestral history in
that region. The ancestors of Bolivians have lived in such altitudes for at
least 2, 700 years (Palomar). The main solutions for Bolivians have been their body’s
capability of producing extra hemoglobin in their blood and excess lung
expansion. These two capabilities increase oxygen carried by the blood.
Being a native to Bolivia, I’ve been told that the
consumption of coca leaves helps with symptoms of altitude sickness. This would
be considered a cultural adaptation by Bolivian natives, as it has been a long
tradition with some of the populace of the country. This adaptation may be
genetically influenced if generations upon generations have consumed the leaf. The
idea is to chew on coca leaves and retaining it in the mouth, swallowing its
juices. Ingesting the juices is supposed to stimulate your body, making you
feel less tired.
There is a benefit to studying human variations from this
perspective across environmental clines, because it shows how humans are physiologically
different based on the different environmental stresses that each live in. For
example, when we look at skin color, we see that this is due to the continuous
stress of solar radiation. Where darker skin tones show that more protection against
radiation is needed and the lighter skin is in need of UV protection.
We tend to think of race as an isolated way to describe someone.
This sort of description pins a person to a certain region where they may have come
from. To some it becomes a tier system to identify another human. But It seems
that a better way to understand our physical differences is by observing our variations
and adaptations to the world; specifically, how we are influenced by our physical
environments. The fact that certain people could adapt to clines such as high
altitudes, shows how the body could adapt for short of long term of time. One would
think that Bolivian people are a race of people that could live well in high
altitude climate, but it really narrows down to how well their bodies adapt to
their clines. Perhaps many foreign visitors to Bolivia would not adapt quickly
or at all, but those that have lived there for generations, are able to sustain
in such environment.



