As a human biology major and as a soon to be fifth year, I’ve definitely had my fair share of courses that talk about genetics and variability but none really touch too much on the evolution aspect. Most of my courses focus more on the human body and its current state and how to medically improve the lives of others. Rarely have we talked about where us humans come from as a whole and our connection to our ancient ancestors and to other species. In most of my classes we learn about the current medical status and more of a general background required for a pre med student, for example: Organic chemistry or Microbiology or biochem. All of these classes are very interesting and applicable for my field but not so much focused on evolution. 

When I was a freshman I wasn’t entirely sure which direction I wanted to go career wise and animals were always a passion of mine so I was originally Animal Science Pre-vet. A lot of the pre-reqs for Animal Science and Human Biology are similar, I did take a class called IBIO 365 which was the biology of mammals. This class talked a lot about evolution and variability but looking at all species dating back to prehistoric times. For example, we learned about the origins of mammals as a whole from over 340 million years ago, and no matter the species, they all stem from something called a stem amniotes which were more lizard like and quite small. Variability is evident in every species, no two organisms are exactly the same which leads to natural selection which then shows proof of evolution.  For example in lecture we talked about the peppered moths and they’ve evolved to have two main phenotypes: dark or light wings. The wing color depending on their environment which allows them to be concealed from predators. 

This past semester I took a microbiology course and we talked a lot about bacteria that exists outside the human body and bacteria that can cause infection in the human body. Antibiotic resistance has become a huge problem all around the world. Resistance is due to either the bacterial cell wall blocking or kicking out or inactivation the drug. In developing countries, according to the article by Alters and Alters, “patients often take antibiotics only until their symptoms go away-killing the most susceptible microbes while allowing those more resistant to survive and reproduce. When these most resistant pathogens infect another host, antibiotics are less effective against the more resistant strains.” In these countries, this is due to lack of funds to cover the entire prescription. While in wealthy countries, resistance is due to overuse of antibiotics and treating viral infections with antibiotics. 

In this weeks lectures and in many of my other classes, human variability and evolution come down to DNA mutations and alterations that get passed down to their offspring. Although many mutations go unnoticed or affect the body in a negative way, some cause phenotypic changes like red hair and fair skin. This mutation is on the MC1R gene and has developed after we separated from our earliest ancestors. Another example is Lactose tolerance, thousands of years ago, the mutation on the LCT gene gave humans the ability to digest dairy and lactose, something we originally were not able to do.