1)Cold is an environmental stress that can negatively impact survival because the body’s temperature synchronized based on the temperatures changes. This happens because the body wants to survive. This can exceed to hypothermia which can kill some promptly if there is no adaption to the circumstances.

2)Short responses may include metabolic rate and shivering which happens when the body temperature drops. When we shiver, our body shivers to try to produce heat by making us muscles tighten to work. This is a temporary stresses until the body warms up. These methods oh heat production require use of nutrients to provide the energy.

Facultative can adapted when the environment is very cold, life can depend on the capacity of our bodies to decrease heat loss and to increase interior heat production.  As Bergmann and Allen observed, the human physiological reaction to cold commonly includes the evolution of additional massive, compact bodies with moderately less surface area. 

Developmental in colder climates have people that live that have a tendency to be stockier with shorter limbs. People living in harsh subarctic regions, such as the Indians of Tierra del Fuego at the southern end, traditionally consumed large quantities of high calorie fatty foods to retain the heat. This significantly increases the basal metabolic rate which results in the production of extra body heat. Peoples in these situations also wear heavy clothing and often sleep in a crowd, and remained energetic when outdoors.

Cultural adapts to cold climates by adjusting to the temperature for example, wearing thick and warm clothes to synchronized the body temperature. In addition, people have developed cultural patterns and technologies that help them adjust to extremes of temperature. People all over the world also become accustomed by restraining outdoor activities to warmer times of the day.  In some societies, sleeping in family groups with bodies pressed up against each other is also done in order to decrease heat loss during the cold months of the year.

3)The benefits of studying human variation across environmental clines are significant. One example is that humans are so diverse that scientist could study he environmental clines which can show the way to a better perceptive of why we look diverse in each region. This can also clarify how certain populations lived where they did and how they survived in those areas. It also clarifies how humans have adapted over time to the cold weathers and how they have developed use of tools and clothing to survive.

4)Race can be understood by the list above because it explains the size and shape of the people for example, the Inuits. They adapted to the cold weather and survived each storm they faced. However, environmental influences have made them adapt and change to what they are in the present day.