Unit 8 Reflection

In this unit we essentially studied why a population's gene pool looks the way it does. Some factors that determine the genotypes in a gene pool include artificial selection, natural selection, evolution, and speciation. Artificial selection, or breeding, occurs when us, humans, select traits from a population's variation that we want, and only mate individuals with those traits. Traits can be selected by nature too, however, and this is known as natural selection. Charles Darwin, a famous evolutionary biologist, drew two simple conclusions from his experiments that explain the results of natural selection. Darwin said that individuals whose inherited traits help them survive better and reproduce more tend to leave more offspring than other individuals. He also concluded that this unequal ability of individuals to survive and reproduce will result in the better traits becoming more common in the population over generations. We tested these two conclusions in our bird beak lab. In Darwin's studies, natural selection caused birds to adapt to the change in their environment and, over time, their species developed new traits that helped them survive. This is known as evolution.

<http://www.yourarticlelibrary.com/evolution/notes-on-darwins-theory-of-natural-selection-of-evolution/12277/>

Natural selection is directly connected to evolution because natural selection is the mechanism of evolution which acts upon the phenotype of individuals. Based on that selection, the population is the actual thing that evolves, not the individual. We also learned about how natural selection distributes its traits in directional selection, stabilizing selection, and disruptive selection. Genetic drift, gene flow, mutations, and sexual selection, along with natural selection, are all factors that can alter the genotypes of a gene pool. Speciation is the rise of two or more species from one existing species, and this is caused by reproductive isolation. Finally we studied the history of Earth, learning about the major events in the development on life on this planet through an activity in which we created a geological timeline of Earth. 

<https://www.pinterest.com/ccoombe0014/geologic-timeline/>

I am still not confident about the concepts of RNA monomers evolving into RNA molecules and then eventually into DNA. I also still wonder: if amino acids could have been the building blocks for life, where could the amino acids come from? What created the amino acids? Or what caused the amino acids to form? 

To be more assertive, I have tried to be direct and honest with friends and classmates about my opinions and needs, trying to avoid being rude or pushy. The challenge for me is avoiding being passive completely by not talking about something I dislike about a person behind their back, but instead, directly addressing the problem by talking to them.