Human Adaptation to the Environment - Variation and Race
The concept of homeostasis is widely used, in physiology and
psychology, to identify what seems to be a general attribute of living
organisms: the tendency to maintain and restore certain steady states or
conditions of the organism. An obvious example is that of body temperature,
which in the human tends to fluctuate only in a narrow range about the value
98.6° F. When the temperature rises above the normal range, corrective reflexes
(perspiration, reduced metabolism, etc.) go into action to restore the steady
state. Persistent deviation may initiate other actions (moving into the shade,
plunging into water, etc.). If body temperature drops, other corrective actions
are observed.
Critics have objected
to homeostatic theory as being too conservative, as implying that motivation is
conceived solely as operating to restore pre-existing conditions. In a very
narrow sense this criticism is true: unless the essential steady states are
restored to their normal range, the organism dies. (It is also true that most
people are conservative unless deprived.) In a broader sense, homeostatic
theory says that energy is mobilized to take action that will restore and
protect these steady states, but that the action may be novel and inventive.
Fire, clothing, and other inventions serve homeostatic uses. The individual,
frustrated by inadequate habits, may acquire new ones which will reduce tension.
1.
The higher elevations weren’t the regional origin for
hominid evolution, various factors in these zones upset homeostasis. Severely
limited oxygen supply results in Hypoxia and affects body tissue maintenance,
and red blood cell health. The brain, heart, and lungs, likewise suffer from delayed
function in environment low in oxygen, the primary energy source being shorted.
The sun’s ultraviolet solar radiation is more intense, the greater elevations
are above the cloud layer, without protection from harmful rays and radiation.
Low humidity, cold temperatures, and rough topography had severe adverse-effects
on homeostasis, forcing the body into change, upsetting the metabolism. Hypoxia
which affects all areas of the body was the most critical to human survival.
2.
a. When it comes to short-term adaptation: One example of
short term adaptation to an environment with high elevations is the development
of acclimatization. This quickly developing adaption permits the body to be
more efficient in a low-oxygen environment, maintaining homeostasis for as long
as possible. After a few days of living within these forceful environments the
body upsurges the metabolic rate, respiration, and heart rate. Non-essential bodily
functions are suppressed providing the best chances for survival.
b. When it comes to facultative adaptation: The increased
hemoglobin-producing red blood cells are a facultative adaptation. The increase
in these cells permits for more hemoglobin production and in-thus more oxygen
transport between organs and tissues, as genes are being switched on or off to
affect a phenotypic expression.
c. A prime example of a developmental /genetic adaption at
high elevations is the way gluclose is processed in the body. High-land Quechua
utilize glucose in a process that allows for efficient oxygen use in their
low-oxygen environment. Glucose is critical for survival, as it is the only energy
the brain will utilize to maintain function. The changes in glucose efficiency
are measured as genetic mutations in MtDNA. These mutations have become more obvious
in these environments, presenting how important an adaption they truly are in
the long-term.
d. A prime example of
a cultural adaptation in extraordinary elevation environments are adaptations
developed by man, and are utilized to endure and thrive. An example would be breathing
masks that climbers use to be able to carry out extreme bodily function in a
low-oxygen environment like Mt. Kilimanjaro. These oxygen masks contain special
bottles containing high pressure chemicals that provide a extended duration of
constant supply of oxygen to the climber.
3. Adaptation is essential in order to survive
and move ahead in the world. The ability to adapt to people, situations and
surroundings affords people a greater opportunity to get what they want and
what they need. Without the ability to adapt, people may find themselves stuck
in situations far longer than is necessarily and unable to reach their goals.
The study of human variation through a wide array of environmental clines accurately
shows how adaptive the human nervous system is. Testing the limits of survival,
and the way in which the body can adapt to such environments leads to added
knowledge about the outer -rims of human potential. This includes mental
capacity, baron survival, and athletics thus giving understanding into future
evolution. This evidence is critical in determining how the body may respond to
a outbreak of an infectious disease, or how a new drug may affect ones long-term
health. These environments push the survival of humanity to greater limits, and
portray the methodology in which adaptation occurs.
4. Using race to understand why or how the human nervous
system adapts to a certain environmental cline is not only inconclusive, but
also inefficient. Race is slightly more than related ancestors who possess like
physical qualities, and/or country origin, giving very little information on
the genetic, environmental, or cultural adaptations a person may have endured. It's
not the skin color, or the genetic likenesses that members of a certain race
possess, more so it's the makings and pressures that previous environmental cline
might have imposed on the human. These adaptations become quite useless in an
opposing cline, the body will be forced into further alteration to maintain
homeostasis. It’s possible the genetic and physical similarities could be used
to measure the slight differences in how certain races adapt to a punishing
environment. The environment forces parallel adaption and change in each
species regardless of racial background. Overall eventually, when placed in a
cruel and unforgiving environment, all people, regardless of race will adapt in
like ways (just at different rates that will in time will more-less even out).
“I am what time, circumstances, history, have made of me,
certainly, but I am also much more than that. So are we all”. – James Baldwin
