Environmental Stress
1.
Heat
waves can lead to heat stroke and dehydration, and are the most common cause of
weather-related deaths. When
core body temperature becomes too high the normal mechanisms for controlling
body temperature break down. Excessive
heat is more likely to impact populations in northern latitudes where people
are less prepared to cope with excessive temperatures. Young children, older
adults, people with medical conditions, and the poor are more vulnerable than
others to heat-related illness. Heat can be a dangerous thing and can
negatively impact the survival of humans by disturbing homeostasis.
Short-Term
Adaptation
1.
Humans
have sweat glands all over their skin. These sweat glands make it possible to
loose heat at the body’s surface through a mechanism called evaporative
cooling. Perspiration is the most important factor in heat dissipation in
humans. This can also be dangerous because it can lead to dehydration.
Facultative
Adaptation
Vasodilation
is a facultative adaptation which helps to eradiate heat. This happens when
capillaries close to the skin’s surface enlarges to increase blood flow to the
skin. This is what causes flushing, redness and warming of the skin.
Developmental
Adaptation
A
developmental adaptation would be body shapes. According to Allen’s rules,
longer appendages, with increased surface are relative to mass, are more
adaptive to warmer climates because they promote heat loss. This rule mentions
that the best body shape for hot climates is linear with long arms and legs.
Cultural
Adaptations
Cultural
adaptations would be the use of shorts, tank tops and flip flops. Most people
try to wear these types of clothing during summer to try to stay cooler.
Another example of cultural adaptations would be eating ice cream and cold
beverages which is not seen as much in the winter.
Benefits
of studying human variation
1.
There
are many benefits in studying human variation. Studying how ones body will
react to environmental changes can prevent us from getting extremely sick or
even dying. For instance, if we did not know that we have to hydrate our body
while exercising in hot weather we would die of dehydration. However, thanks to
science we are aware that we need to replenish our bodies with electrolyte when
sweating profusely to avoid dehydration.
Understanding
the variation of adaptation
2.
Before
I say anything else, I will like to say that this was by far my favorite
chapter. I often get annoyed when people assume I should look a certain way
just because I’m Mexican. Same thing with adapting to certain environments. For
example, when I go to Mexico I always get sick from my stomach. I cannot drink
water from there, so I have to make sure I take my own water. My point is that,
because I’m from Mexico I should be able to drink their water with no problem!
No! This is why it so important to study environmental influences on adaptation
because being from a certain “race” does not mean you will adapt to certain environments
better than others. Adapting to the heat is not a matter of race is a matter of
how your body reacts and gets used to it.
