Our Variation

          Long exposure to heat from the environment or infections disturbs homeostasis. Once the core body temperature starts to reach 40.6 degrees celsius it enters hyperthermia. High temperatures and high humidity are more likely to cause hyperthermia. High humidity in the air makes it harder for our bodies to receive the cooling effects of perspiration. Blood vessels begin to dilate in a struggle to increase the dissipation of heat. The heart pumps faster the lungs cooperate, blood pressure begins to drop. The body makes wild attempts to maintain homeostasis. Without any cooling taking place the decreased blood pressure causes blood vessels to contract. The body begins to feel faint organ failure soon follows then the inevitable...death. 

         What is a short-term adaptation to heat stress? Perspiration or sweating is the way our bodies have adapted to heat. When sweat evaporates off of our bodies it offers a cooling sensation. 

          Fainting is a facultative adaptation to heat stress. This action puts the body in a more relaxed state and allows oxygen to flow more efficiently throughout our bodies. This is preceded by rapid heart rate and breathing which serve the same purpose. Fainting helps to concentrate the the energy available to help cool the body. At this point breathing normalizes and restores oxygen flow. 

          Slimmer and longer bodies are a developmental adaptation to heat. A slimmer longer body is able to disperse heat more efficiently. There is also less body area exposed to sunlight (which increases heat). A slender body means less cells. Cells help to produce heat and with less heat being produced the body is better able to cool. 

          Most common in the U.S. air conditioning is a cultural adaptation to extreme heat. With the press of a button we are able to alter the environment within our homes, buildings, and cars. We no longer have to suffer the triple-digit heat waves (if you can afford it). 

          Learning how our bodies react to a certain environment allow us to find ways to survive in that environment. We can learn what to avoid and what to do. During hot summer days in the desert you know it's not healthy to exert yourself without proper hydration and cooling. This helps us create technologies that allow us to adapt to environments. From hand-held fans to aqueducts we make an environment suitable. 

          Race would not be adequate in helping us to understand the variations in adaptation. People with long slender bodies come from all races. All humans also have the ability to faint and sweat. Cultural adaptations to heat vary from region to region mainly depending on economical status. In some places extremely loose clothing and turbans allow for cooling while in others a lack of clothes and swimming pool does just. Environmental influences are a better tool for understanding adaptations. There is more of an emphasis on the reactions of the human body to a stimulus and how over many generations it has been molded in response to that stimulus. Instead of looking at physical characteristics then asking questions later.