High levels of solar is an environmental stress that has a negative on the homeostasis of humans. Due to high level of solar people who live in places where the UV percent is higher are known to have more melanin, which control the pigmentation of the skin. Melanoma is one way that the sun creates skin cancer. Another harmful disease that can start from high level of solar is anemia because the sun penetrates into the skin an breaks down vitamins.

A short term adaptation that happens to the body when it starts getting hot is that sweat starts to be releases from the pores in order to lower the temperature in the body and return to homeostasis.

A faculatative adaptation that happens because of the sun rays is that people who are exposed to much higher UV rays tend to have darker skin to help the amount of sun rays the body captures. The chart above illustrates the different skin colors according to the location.

A developmental adaptation happens throughout generations due to alot of sun that with time the body develops a certain metabolism that reaches a certain temperature that is homeostasis.

Cultural adaptation when it comes to high solar rays is influenced by the location. People who live in hot tropical temperature wear less clothes and spend more time outside than people who live in the cold temperature.
The benefit from studying humans variation across environmental cine is that allows us to explore the possibilities of genes that are evolving. It also helps us learn more about distinguished traits that certain cultures have passed on through generations.
Race has much in the understanding of variations because every culture is different that have certain traditions that have allowed them to survive. Due to the different cultures this will allow us to compare the techniques of different cultures that will allow us to understand the geographic and requirements of surviving every different origin of race.