1.Heat is an environment stress that has a negatively impacts the survival of humans by disturbing homeostasis. The human body temperature for normal cellular function is approximately 98.6 degrees Fahrenheit. Heat has high UV light which can result a risk in skin damage. Heat can affect the body temperature and hydration level of an individual.
2.Perspiration is a short term adaptation that allows the human body to respond quickly to the heat in the environment to main homeostasis.
The facultative adaptation to heat conditions is vasodilation. The effect of this is flushing, which increased redness and warming of the skin.
A culture adaption can be wearing summer type clothes like tank tops and shorts. Another adaptions is having air conditioners in every house hold when it comes to the hot weather.
3.Understanding evolution and genetic mutation are benefits of studying human variation from this perspective across environmental clines. This information can be explored to understand different skin color, diets, behaviors, or any physical appearance.
4. To understand human variation you need to understand the study of environmental stress around them. People around the world are expose to different amount of UV radiation for vitamin D synthesis, which influence their skin color.Race cannot be use to understand the variation of the adaptations.
I enjoyed reading your post. It was very straight forward and to the point. I do agree that heat is a very important environmental factor in the survival of humans. Weather we know it or not the climate of the earth right now is the coolest its been since the last ice age. We are creatures that have have to operate at that magic 98.6 degree F or our bodies begin to react in all sorts of ways. You also mentioned sweat, we sweat in order to cool down our body temp and is why when we are sick we get the cold chills even though we have a fever. Our bodies are trying to cool down while the sweat is first cooling off our external.
ReplyDeleteThe T-Rex meme really made me laugh. But you have to also think that the T-Rex was cold blooded if Im not mistaken. And that would mean a very warm climate would favor them in keeping itself in homeostasis. As far as I know there are no lizards in cold climates due to the fact that natural selection has froze them all to death. I really did enjoy reading your post, very entertaining.
Heat and solar radiation are actually two different stresses. Make sure you understand that. Heat stress increases sweating and can cause dehydration, but what is the danger of the heat stress itself causing a rise in body temperature? Why can't our temperature rise without causing problems?
ReplyDeleteYes, sweating is a short term response. How does it help with heat stress?
Vasodilation is a facultative response to heat stress. You have described what it looks like, but how does it help with heat stress?
Good job pulling in Bergmann and Allen's rules, but how does a long lean body help in a hot climate?
Okay on your cultural adapation.
Well, you can understand evolution and genetic mutation without studying human variation, correct? What is the specific advantage of studying human variation using the adaptive approach? How is this approach more productive than other approaches? What concrete benefits do we gain? What can we do with that information?
I agree that race can't be used to understand human variation, but while you explain why you can do so with the adaptive approach, you don't explain why you can't with race? What is race missing that the adaptive approach has? Is there a causal relationship between race and variation like we see when we compare the environment to our adaptations? If race doesn't cause our variation, can it be used to explain that variation, or can we only use race to categorize human populations?