1.
Heat negatively impacts the survival of humans by disturbing homeostasis
because it can be costly and hazardous in terms of water and sodium loss. There
are two kinds of heat – arid and humid. Arid heat is primarily found in the
southwestern United States, Middle East, and in some parts of Africa. High
temperatures, wind, and low water vapor is indicative of arid heat. Humid heat is
primarily present in eastern and southern U.S., parts of Europe, and in the
tropics. Unlike arid heat, humid heat is characterized by large amounts of
water vapor. Increased water vapor obstructs the evaporation of sweat, which
makes it less difficult for humans to adapt to dry heat. People who workout in
areas with dry heat may be unaware they are sweating altogether, because it
evaporates as soon as it reaches the surface of their skin. This rapid
evaporation can quickly cause dehydration, which stresses the importance of
staying hydrated, regardless if you are thirsty.
2.
Humans have adapted to heat through several different effects including: short
term, facultative, developmental and cultural.
A short term response to heat
could be something as simple as perspiration. Sweating is a natural reaction
produced by the body’s cooling system.
A facultative response to heat would be
developing a slender body type, which would allow more heat to escape by
sweating more efficiently.
A developmental response to heat could be understanding
the importance of drinking plenty of water. In areas where high temperatures
are evident, staying hydrated is necessary for proper body functions.
A cultural
effect to heat is understanding the importance of clothing. People should dress
appropriate and protect the skin from damage.
3. The importance of studying human variation is
that it allows us to understand how people live in drastically different climates
and environments. Being a native to a particular climate gives basis to the
adaptation anyone has for survival. For example, living in Southern California
has spoiled me into believing that anything below the mid-sixties is cold. This
drastically limits the number of places I would be able to survive in the
world.
4.
I don’t believe race plays an actual role in human variation. Race is any
people united by common history, language, and cultural traits. It is not
defined by skin color. Environmental effects on adaptations lead to solid
non-racial explanations for why people have become the way they are.
Great opening discussion and wonderful images.
ReplyDeleteHow does sweating cool the body?
Yes, we do tend adjust our body shape (and food intake) over time if we stay in a hot climate for an extended period. Another example is vasodilation to dissipate heat.
A developmental adaptation is a biological/genetic change in the body. Understanding the need for hydration is a cultural change, not a biological one. The body telling you that you are dehydrated and need to drink water is a short term physiological response, but not developmental.
Your discussion of body shape better applies to the developmental adaptation. Populations that have spend generations in hot climates tend to have longer, thinner body shapes. This is related to the Bergmann/Allen rules and allows the body to throw off excess heat more readily.
Clothing does come into play for heat, but I'm not sure what you mean by "appropriate". We aren't talking about solar radiation stress, so protecting the skin isn't the issue. How can you dress to solve the problem of heat?
Okay on section #3.
You are on the right track in the final section, but race isn't even as you describe it (common history, language and cultural traits). You are describing ethnic groups, not races. The problem with race is that it is a social construct and subject to bias. Otherwise, good final discussion.
I also did heat as my blog! Really the only difference I did on mine is that the urine becomes decreased the more you become hotter. It allows us the have more sweat, but from what I've found out, it isn't a great thing for a long period of time. I should've put drinking water as my third one! I didn't even think of that, but great post!
ReplyDeleteI really enjoyed your blog post , it was great having the pictures under each statement . I also enjoyed how you explained both kinds of heat like the arid and humid . That was great that you explained them well.Great job .
ReplyDeletethank you
ReplyDelete