Ian's Thoughts

 Phenotype Plasticity -       Phenotypic plasticity is a concept that I struggled to understand fully until recently. I've heard about it in other classes like the genetics class that I have taken previously, but I didn't go into much depth researching it. I would define phenotypic plasticity as "The ability of organisms to produce different phenotypes in response to an external environmental change". I'm not sure where I stand on whether phenotypic plasticity slows down evolution or potentiates evolutionary change. I think it varies based on the situation and the availability of genes in the gene pool. I think if I had to choose one, I would say phenotypic plasticity slows down evolutionary change only because a population doesn't have to make hard changes by evolving when being introduced to a new stimulus in their environment. Instead, they can rely on phenotypic plasticity to change accordingly and if the stimulus goes away, then they can revert back to ho...

 Genetic Variation-      Both genetic variation and natural selection are good things for populations, but selection would not exist without genetic variation. If there were no different traits to choose from, then selection would not be needed. Genetic variation is not eroded over time because even though the simulations done in the R exercises show a tendency for populations to fix on a better trait over time, these are done in closed systems, with the assumption that fitness for specific traits does not change over time. In real life, the ecosystem a population lives in might be very different from one area to the next, even though the same species lives in both. It's safe to assume that one population that lives in one area would not have the ideal traits to live in a different area. Interbreeding between two different populations introduces new genes to the populations, which increases genetic variation. On top of that, ecosystems can change over time. If one tr...

 Taking Stock Since we've begun class, I've realized that there is so much more that contributes to evolution than I had previously thought. The biggest breakthrough to me was realizing that evolution is all caused by mutations. I hadn't completely realized that until this class, I just figured natural selection and genetic drift and other methods of evolution like that just happened. Now, I realize that at the base of it, all evolution is at least in some way started by mutations in genes and DNA that cause the methods of evolution to actually work.  Looking back on my first blog post, I would change a little, but not much. One thing I do need to change, however, is my previous statement that is "Evolution is how organisms change from generation to generation". It should be "Evolution is how overall populations change from generation to generation", this is more accurate as organisms themselves don't evolve, but populations do. My understanding of e...

 Inbreeding          Inbreeding is a bit of a tough subject that is often common in nature, but not in humans. It has both pros and cons that will be discussed in this blog post, as well as my thoughts on it. One of the pros of inbreeding is that it can concentrate genes of a superior organism in a population, and overall increase the population's fitness. If one organism has traits that increase its fitness by a large amount, it makes sense that the entire population would want these traits as well. Inbreeding can help fix these desired types much quicker than it would be done if reproduction was random. As we talked about in our last R exercise, fixing is when a set of alleles in a population either becomes entirely recessive or entirely dominant. On the flip side of this, inbreeding can also concentrate and pass on any of the undesirable traits that an organism might have had along with the desirable traits. In humans, inbreeding is a social no-no nowada...