This unit revolved around the concept of evolution, specifically what drives evolution and its effect on other populations. Evolution is caused by either artificial selection or natural selection. Artificial selection is calculated and less random than natural selection, in the sense that artificial selection has breeders breeding a specific population for the best, desired traits. Natural selection is the survival of the fittest, as the traits that don’t help the individuals survive get weeded out and the better traits become more common in the population, as concluded by Charles Darwin.
As the better traits become more apparent, the population is evolving, and the best evidence to support evolution is the measuring of genetic variation. In order for evolution to be occurring, the allele frequency for the desired trait will increase, showing, genetically, that the population is starting to look like winners. In the Hunger Games Lab, we were able to see how competition and other external factors lead to the population looking like winners.
But as the population evolves, the different traits can cause different species to come about, which is speciation. We learned about two types of speciation, one being gradual speciation where new species arise very slowly and after many generations, and the other being punctuated equilibrium, where the new species arise suddenly.
There is much evidence out there showing that evolution has occurred, but the best evidence comes from fossils. With fossils, scientists can physically observe the changes that had happened over time instead of inferring a common ancestor.
Towards the end of the unit, we learned about how long evolution truly takes. I had been struggling to truly understand how long this process really is, but the geologic timeline truly put it into perspective.
I also learned how to become more assertive throughout this unit. By really understanding the concepts, I started to become more confident in my knowledge and thereby more assertive.
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