The Argument- Kenyans have recently been dominating distance races, and the majority of these runners come from a specific tribe (103). It was found that certain environmental circumstances greatly influenced their passion for running, and therefore their extraordinary abilities. How do their circumstances relate to those in history that have influenced evolutionary adaptations? What are some examples of evolutionary adaptations in animals to improve their chances of reproduction? After reading the Genius in All of Us, do you think the runners are born with talent? Based on the GxE theory, what do you think would happen if a newborn from Kenya were to grow up in America? Use evidence from the book.
The circumstances seen in the Kalenjin tribe is also seen in the discovery of the Tiktaalik Roseae, a keystone in the evolution from fish to tetrapods. Due to the harsh environment, the animal had to adapt to survive and reproduce; to survive in the shallow, oxygen deprived waters, fish had to adapt to be able to go onto land if necessary. The tiktaalik roseae had basic outlines of limbs such as wrist bones and basic rays. While it is doubtful that the tiktaalik roseae could walk, the wrist also showed muscle and ability to carry weight, which would act as an anchor during tides. The adaptation for limbs was to travel on land, and there is evidence Tiktaalik Roseae had both primitive lungs for oxygen processes, and gills, for oxygen and material diffusion in water. There are also signs of a more robust ribcage, which helped support the body after leaving a fully aquatic environment. Tiktaalik Roseae is also the earliest organism known to have a neck, which aided in finding prey on land. After reading the Genius in All of Us, it’s evident that no “talent” gene is needed to be talented, but some runners may be born with advantages such as increased expression of muscle fiber genes and bigger lungs, heart, etc. The reason why many Olympic athletes originated in Iten, the small village in Kenya with some big talents, is because of the daily requirements of running long distances. By running eight to twelve kilometers each day since they were very little, people in the village got the same effect as a cross-country trainer. They also had some great conditions for training, coincidentally, such as high altitude training which developed their lungs and heart to pump blood and oxygen more efficiently, and great climates for running which let the body use less energy for body temperature regulation while letting the muscles perform at optimal conditions. However as noted before, practicing by itself is not enough; motivation and determination to always be better is key. As it turns out, psychologists determined that many from the Kalenjin tribe have a strong “achievement oriented” culture and strive to outdo others (Shenk 105). There was also an incentive for running: to reproduce. As journalist John Manners states, “The better a young man was at raiding cattle-in large part a function of his speed and endurance-the more cattle he accumulated” (Shenk 103). And as a man got more cattle, he could afford more wives, which would mean more reproduction. Kenyans such as Kipchoge Keino from the Kalenjin tribe were not born with a special talent for running, but their environment forced them to develop the body to run. If a newborn from Kenya were to grow up in America, he would have much less of a chance of becoming as good a runner as someone who grew up in Iten. The environment in Iten is much more suited for developing a runner due to its high altitude, its weather and temperature, and ultimately the need to run to survive and reproduce. The Kenyan that grew up in America might have more developed lungs than most American children due to many generations of living in high altitudes, but that advantage will not make him a great runner. As seen in the experiment performed on two Japanese children growing up in two different countries, the environment can affect the expression of genes dynamically. In the experiment, one Japanese child grew up in America, while the other grew up in Japan. The height of the Japanese child that grew up in America was 5 inches taller than the child that grew up in Japan. It is very hard to run eight to twelve miles every day in America while training your respiratory system to use less oxygen. Therefore, it is likely that the Kenyan child growing up in America will have a lower chance of becoming an Olympic runner than someone from Iten.
ReplyDeletehttp://www.nature.com/nature/journal/v440/n7085/abs/nature04639.html
http://en.wikipedia.org/wiki/Tiktaalik
Yiran Xu, yxu135@gmail.com