Humans are constantly evolving in ways that most people do not even think about. One who studies evolution may wonder why our bodies were built the way they were. If natural selection favors better evolutionary traits, then why do our bodies still get sick? Why do we still experience pain? What scientists have determined is that these traits are not disadvantages, but they are actually defenses against what could kill us. For example, vomiting is a way that the stomach can protect the body against harmful gasses. While it may seem unpleasant in the moment, the gasses that were removed in the process of vomiting could have been deadly. Morning sickness among pregnant women acts as a similar defense system.
In a way, these responses continue to evolve to be like “smoke detectors”. A smoke detector is meant to wake people up and alert them of a fire. While these fires could be dangerous, in order to do its job, the detector must also alert people of the slightest dangers such as burnt food in the oven. Even though these false alarms would not have killed someone, the detector is set up to be triggered by even the slightest thing in an effort to keep people safe. Much like these smoke detectors, our bodies respond to even the smallest threats by vomiting, coughing, running a fever, etc. For example, if people never coughed, they would not be able to remove foreign substances from their bodies. While not coughing one time may not have an effect, never coughing would cause people to die of pneumonia. So the body must react to every instance.
Due to studies, we can also link evolution to the increase in heart diseases. During times of famine, natural selection favored bodies that were able to eat more fats because they were more likely to survive than thinner people who were not getting as much fat in their diet. So over time, we evolved to favor diets higher in fat. This is why our society has become dependent on fast foods and other unhealthy items. When eaten in moderation, they are necessary, however we evolved to crave fats, and now we suffer the consequences of eating too many fats.
Another example of evolution in current society is how young some girls are beginning to menstruate. It used to be that girls would begin at age 15, bear a few children while menstruating in between, and then stop. However, this is not the case anymore. Nowadays, females begin at age 12 or 13 and do not bear children for many years after that, if ever. Females used to average about 150 cycles as opposed to 400 now. This is because the diets we now consume allow women to be able to nurture a child at a younger age.
One final example that was not mentioned in the reading that I have always found interesting is wisdom teeth. While the majority of my friends simply believe that everyone has wisdom teeth and most people get them removed, they are mistaken. I, along with multiple members of my family, were born without wisdom teeth. Since they serve no function in today’s society and are consistently removed, I believe evolution is causing some people to simply not have them.