One of the main environmental stresses that has been put upon the human race is getting through the cold. The cold is very important to stay away from in order to survive because it could be life threatening. One can either get used to the cold weather or one can get really sick and develop hypothermia which is when ones body falls below required temperature.
2. -There are many ways to see that one is cold, but the most obvious is when one has red cheeks. having red cheeks is when ones body temperature falls. This is a Facultative adaptation because ones DNA does not change but their genes do turn on and off when they get cold.
- Another adaptation would be a persons body mass, which in all technicality the bigger you are the less you will get cold. When one has more to hide their skeleton they are less likely to become cold. This is called a Developmental adaptation, this is when it is in our genes or DNA to be thicker than we used to be.
-Shivering is a short term adaptation because a persons body is too cold to handle so the body starts to move faster and faster in hopes to warm up. Our bodies only do this for a short period of time.
- Lastly a cultural adaptation to cold is clothes. Humans have learned that wearing clothes will actually help them warm up.

3. It is more beneficial for humans to study humans through environmental clines because through the clines we can see the parts of natural selection and will give us a chance to see how we adapt and change.
4. Using race to understand variation in adaptation would be very subjective, because it would only teach us how one race is and all races are not the same some may be similar but many are complete different. For race in environmental stresses with cold goes for almost most races, a few races get hotter or colder easier but they all do the same because that is how humans in a whole adapted. Environmental influences is beneficial because people study the whole environment and get a feel for every race; whereas, just studying race will take too long to look into each one and every race is different so you would have to look at each and every race individually.