Wk 7

Evolution is a never-ending process from which humans are not excluded. There are multiple ways in which modern humans are continuing to evolve to this day. Through human biology, behavior, environment, and culture, it is easy to see evolution taking place. Through the Bio-Cultural approach, it is understood that cultural behavior led to biological variability among humans. This variability includes, but is not limited to, migrations, technology, religion, food production, and political and economic structures. Gene flow is an important part of modern evolution. Gene flow patterns are altered through the cultural influence on the movement of people and genes. Some of these movements include events such as war or trade. But gene flow is not always encouraged. Factors such as language, ideology, and economic status can even restrict gene flow. Genetic drift can also play role in modern human evolution, but is not as likely anymore due to populations becoming larger and more connoted. But still, war, famine, disease, and strict cultural rules can result in population reductions.

The processes of natural selection and mutation greatly affect human evolution. Through the process of natural selection, different traits are able to be passed on and become stronger. For humans, disease is an issue that natural selection has made more difficult. This is due to the fact that new diseases can arise and spread. But the environment heavily influences natural selection through disease, food resources, differential reproduction, and climate change. Although natural selection has the ability to work quickly or slowly, the effects of mutations is slow. Mutations can have great impacts on a population over time, though. It is been believed that humans themselves will be able to control gene mutation through genetic engineering.

As mentioned in this weeks lecture, there is a great deal of correlation among the influences discussed on human variability. Similar to the idea of biocultural approach, these influences affect one another in different ways. For example when a population migrates, it is more than just a movement of people. Economical factors along with general human behavior can make a difference.

As discussed in Randolph Nesse and George WIllaims’ article “Evolution and the Origins of Disease,” there are many mysteries of the human body than only evolution can explain. Some of the details of the human body are almost magically perfect, such as the eye. The eye has “clear living tissue of the cornea curving just the right amount” and an ability to adjust to any light. It is clear that human eyes are a product of natural selection for our preferred environment. Another incredible physical trait humans possess is the simple ability to cough. Through this action, humans are able to clear their lungs of foreign matter and stay alive. But even the evolved human body has its unexplainable faults. For instance, although the body’s immune system can destroy millions of foreign matters that may enter the body, many bacteria can surpass it. In the words of geneticists Theodosius Dohzhansky, “Nothing in biology makes sense except in the light of evolution.” After looking at the human body, it is clear that that much is true.

Nesse, Randolph M., and George C. Williams. “Evolution and Origins of Disease.” (1998): Scientific American, Inc. Web.

One thought on “Wk 7

  1. It’s interesting to think how different our gene flow is now, compared to even 50 years ago. While this is not the same all over the world, I feel as if many of the barriers that have restricted the exchange of genes from population to population have weakened considerably. Distance is one the most obvious example. While groups are not physically closer, our ability to travel from one area to another has increased significantly. Accessibility to incredibly fast forms of transportation has become the norm. What would once been a harrowing journey across the world can now be done in less than a day. That plus a growing acceptance of interracial relationships will produce mixtures of traits that seem novel today, but might one day be the norm. Will that be the future of human revolution or will genetic manipulation be the answer? What will our descendents look like and how will they adapt to their environment and culture? It’s difficult to say natural selection will continue to guide us, to say it will ensure our best chance of survival, when we have taken so much control over both the nature and selection sides of the equation.

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