1)
Heat negatively impacts human’s survival because
it causes the body to rise to dangerous temperatures. This can result in
dehydration, heat syncope (fainting), heat exhaustion, and heat strokes, which
can potentially cause damage to the brain or death.
2)
Short
term adaption- Sweat is a short term form of human adaptation towards
heat. The human body produces sweat as a way of cooling itself down. Studies have shown that it is easier for
populations to withstand the dry heat of the dessert better than the humidity
from the tropical areas. This is because the sweat we produce is easily
evaporated, providing us with a quick cooling sensation, while in humid areas
sweat cannot evaporate quick enough.
Facultative
adaptation- An example of facultative adaptation to heat is peripheral
vasodilation. This involves the dilation of blood vessels in the skin, bringing
large quantities of warm blood from deep within the body closer to the skin.
This is what causes your skin to become red or flushed when you are hot. The
heat that was brought closer to the skin can then be removed by radiation or
convection.
Developmental
adaptation- One developmental adaptation humans have grown into through
the help of numerous generations is bipedalism. Although this is currently just
an unproven theory, it is still a possibility that we have adapted to heat
overtime. Many scientists believe that our early ancestors evolved from being
quadrupedal to bipedal to escape the heat that is closer to the ground. Our
ancestors could have also stood on 2 feet in order to avoid the direct sunlight
that would normally hit them if they were on all fours. This could also have
been the reason for our tremendous loss of body hair overtime.
3)
One benefit of studying human variations through
environmental clines is the ability to observe humans beyond race and
ethnicity. Yes, information from explorations can be useful because the can
provide us with ways to overcome the heat stresses. Scientists can observe how
people living in hot environments deal with the heat. They can then bring this
information back and use these methods to help people that are suffering from
heat exhaustion in other parts of the world.
4)
The study of environmental influences on
adaptations is a better way to understand human variation than by the use of
race because we are all human. In my opinion, you cannot use race to understand
the adaptations human have made to deal with heat. Heat affects every race, and
there is no one race that was born with the ability to withstand high
temperatures better than others.
I really like the layout of your blog, it was neat and the information was set up so that it was easy to read and understand. I really enjoyed your pictures. You did a great job with this blog. Good luck on the final this week.
ReplyDeleteAbsolutely love your blog. I think yours is one of the very few that i always comment on lol. Anyways, the pictures are great, the layout of the questions are very well organized and easy to read, your explanations are in depth yet understandable. Great post
ReplyDeleteNote: Late submission.
ReplyDeleteGood discussion of the impact of heat stress on the human body.
Very good explanation for how sweating serves as a means of dealing with heat stress in the short term as well as you coverage of how vasodilation works as a facultative trait.
I appreciate that you raised the point of bipedalism as a possible developmental adaptation to heat stress, along with the qualification that this is still "in the works", so to speak, with regard to empirical support. Make sure you understand the tried and true developmental adaptations to heat (and cold) as explained by Bergmann and Allen's rules (in the assignment file's supplementary information).
Good cultural adaptation.
Good application of the information gained from this approach in a productive way. Information on how the body adapts and why can lead to innovations in new tools, clothing and homes that help deal with heat stress but also in the medical field.
"Heat affects every race, and there is no one race that was born with the ability to withstand high temperatures better than others."
Really? I would argue that point. Equatorial populations are indeed born with traits (body shape, for example) that help them adapt to hot climates better than, say, populations in polar climates, correct? But I do understand your point, though it needed additional clarification, taking it a little deeper.
Race is a social construct, a human-generated system of organizing and classifying people into artificial groups based only upon external phenotypic expressions. Unlike the environment, race has no causal relationship with human variation. It does not cause our adaptations, it only groups them and categorizes them. Without that causal relationship, race has no explanatory power.