Since the beginning of time, we humans have been vulnerable to our surroundings; thus have always sought out environments with certain qualities that our bodies can resist without being susceptible to any harmful consequences. Everyday our bodies work to keep us alive, regulating temperature, fluid levels, breath, and heart beat; however, what about in extreme situations?
Many shows such as “Survivor”, the “Spartan Show”, and the “Biggest Loser”, as well as various news stories, showcase human survival instincts, proving they are able to adapt and survive in seemingly impossible situations. In fact, the human body has built-in mechanisms and responses that help humans adapt to various situations; hence, survive. Most human beings will never be subjected to extreme situations, such as extreme temperatures or weeks without food; however, it is interesting to learn how the body responds to extreme situations and adapts as it goes into “survival mode”.
One of the toughest challenges for the human body is mountain climbing; mentally and physically speaking. Climbing Mount Everest is considered the most dangerous climbing environment at 8,850 meters above sea level, which is the same altitude that planes reach during flight.
Oxygen drops to 6%, which is third the volume of Oxygen at ground level, temperature is less than -40˚C, and wind speed is more than 150 km/hr; it takes a minimum of two months to get to the top of Everest.
The human body is able to stay alive for a while in extreme temperatures as it is equipped to handle changes in temperatures. If a human being is in a very hot environment, he/she can experience hyperthermia—increased body temperature. On the other hand, if he/she is in a very cold environment, he/she can experience hypothermia—decreased body temperature. Both cases are equally dangerous, especially when continued for a long time.
When the body is very hot, it sweats to cool down; however, a person can only sweat for a certain time before it starts to need water to compensate for the sweat. When the body is very cold, on the other hand, it will send blood to the core and start to shiver to stay alive, but this cannot go on forever.
Among other extreme conditions is sleep deprivation. The average person can only stay awake without sleep for about ten days; however, the longer the person is awake the more he/she will experience loss in concentration and motivation.
A not-so-extreme situation, but nonetheless not-so-comfortable, is traveling. Travelers using ships, cars, or planes may suffer motion sickness, which is a very common disturbance of the inner ear that is caused by repeated motion. The symptoms of motion sickness are vomiting, dizziness, and a sense of feeling unwell; these symptoms arise from the inner ear due to changes in one’s sense of balance and equilibrium.
From an emotional perspective, when someone is frightened for example, bodily responses are initiated by environmental signals that are received by the brain through the eye and then passed throughout the whole body. The body releases hormones such as adrenalin, changing a variety of nervous system functions, speeding up the heart rate and blood flow to the body’s major muscle groups by contracting or relaxing these muscles. Once the danger or threat is gone, the body is designed to go back to functioning normally.
The human body is without a doubt a perpetual wonder; its capacity to deal with changes, the extremity of which can be unimaginable, is truly amazing. Studying this ability and the myriad of mechanisms employed by the human body to survive is a quest that has no end, yet is a necessity as humans face increasingly dangerous changes, climate change to name one.
References
brighthub.com
nss.org
learn.genetics.utah.edu