Human Variation & Race

I chose the environmental stress of a cold climate. This environmental stress negatively impacts the survival of humans by disturbing homeostasis. When humans experience cold climates, they will have an increased metabolic rate, they will shiver, and they will experience vasoconstriction. If these things don’t help, they might even experience hypothermia or even death.

Four ways that humans have adapted to this stress are by short term, facultative, developmental, and cultural responses.

A short term response that humans have used to adapt to the cold is shivering which can help generate body heat and muscle heat for a short amount of time.

A facultative response that humans have used to adapt to the cold is having involuntary changes in vasoconstriction which narrow blood vessels to reduce blood flow to the skin and then reduces their body’s heat loss.

A developmental response that humans have used to adapt to the cold is having large compact bodies that have more fat insulation around their vital organs.

A cultural response that humans have used to adapt to the cold is using insulating clothing such as heavy jackets and pants to combat the cold climate.

The benefits of studying human variation from this perspective across environmental clines is to see how humans vary in their ability to adapt to cold climates and find out why certain groups of people can adapt better to the cold climates while others cannot. For instance, we can find out why people like the Inuits were able to experience periodic warmth and avoid frostbite in below freezing temperatures, while someone like me would more likely experience frostbite in a short period of time.

Information from explorations like this can be useful to help us because it might give us a better idea of what we need to do if we would like to one day inhabit an area in which the climate is very cold. For instance, people are always looking for new envirnoments in which to build houses and attract new residents, so in being able to tell prospective residents that it's easy to live in cold climates if they just follow these simple steps will help them appeal to those people and maybe help them sell houses faster. One example of how this information can be used in a productive way is by studying vasoconstriction which is a short term response to the cold climate. In studying this, manufacturers that specialize in cold weather clothing can figure out more productive materials that will help reduce heat loss at the body surface like vasoconstriction does.

I would use race to understand the variation of the adaptations I listed in number two by saying that in regards to the cold climate, people that had a darker skin pigment were at a disadvantage for Vitamin D production which helps with bone growth and regulates neuromuscular functions. The study of environmental influences on adaptations is a better way to understand human variation than by the use of race because people of the same race can still vary in their ability to adapt. For instance, even though the Inuits had dark skin pigmentation, they made up for their vitamin D disadvantage by eating lots of fish and mammal blubber that contained vitamin D.