 |
|
|
|
|
| NCLC 120 began by introducing the theory of evolution. The book, The Making of the Fittest,
explained of the main ideas in this theory. The first idea was natural
selection, and the second idea was descent with modification. It
explained that natural selection is the process that drives the
evolution of a species and allows for favorable traits to be retained
and passed on while unfavorable traits are selected against. It also
explained that the idea descent with modification means that all living
species descended from one common ancestor, and over time, they have
changed in the course of descent. At first, I had some false ideas
about natural selection, but through discussions in class and the film,
What Darwin Never Saw, I was able to fully understand the idea. When I first read about natural selection, I did not fully understand it. The book used the icefish and how they no longer have red blood cells as an example of natural selection. it said that the water temperatures cooled down significantly where the icefish lived, and in order to survive, they allowed their Hemoglobin genes to disintegrate. I thought it meant that one day, the icefish realized the water was too cold for it to live, and the fish decided not to make red blood cells anymore. Through a discussion in class, I was told otherwise. The next day in class, One of my fellow classmates asked a similar question to the idea I just descibed. He asked how fish or and species could decide to not use a part of their body like red blood cells. Professor Gilmore quickly explained that an individual species does not decide or allow anything to stop functioning. He said that individual species do not evolve. Only populations of species evolve through natural selection. With this explaination, I began to understand natural selection, but I could not see how it worked in real life. |
During the next day of class, we watched a film called What Darwin Never Saw,
and it showed me how natural selection worked on a population of
finches. The Grants studied a group of birds called finches on an
island. There are small beaked finches and large beaked finches. During
their studies, they witnessed natural selection working on the species.
One example of natural selection occured during a drought. Many of the
finches with small beaks died because they could not get enough food
from the tiny seeds that they ate. On the other hand, the finches with
the large beaks survived because they could eat the large seeds and get
more nutrition. When the Grants examined the population of finches
after the drought, the average size of the finches beaks was 3-4%
larger than the previous year. This film showed me a real life example
of how natural selection works on a population and not an individual
species. Through discussions in class and a film, I was able to better understand natural selection. It took me a while to put all the pieces together, but I was finally able to make the connection. This is an example of how I sharpened my critical thinking skills. I took what I learned in the book and applied it to the discussion in class. When I was told that natural selection worked on populations rather than individuals, I did not see the connection right away. Once we watched the film, I fully understood the idea and was able to make the connection. I had to use severa different resources to help me understand. |