fandomhigh | Evolutionary Science for Beginners

Connor was feeling the best he had in some time, but there was still the necessary cup of coffee on the desk, though he wasn't clinging to it quite as desperately as the last few weeks. “The topic for today’s class is the theory of natural selection” he said as he started the lecture when it was time. “This is one of the foundational theories related to evolutionary science and many other fields of science such as biology, botany and the studies of plants and animal species. It has undergone some changes from its origins as more discoveries are made and more research has been done. And this is a good thing, it is how it is supposed to be with science and theories- they get tweaked and changed as new information and data becomes available,” Connor looked over at Cutter and nodded to see if he was ready to go with the next bit of the lecture.

Cutter was also feeling pretty good about how things had been going but he also still had his large cup of coffee with him, “Charles Darwin and Alfred Russel Wallace are credited with coming up with the theory of evolution by natural selection,” he continued on with the lecture, “natural selection works by genetic mutations that are beneficial to an individuals survival are passed on through reproduction and the result is a new generation of organisms that are more likely to survive to reproduce,”

“An example of this is through giraffes and that the evolution of their long necks has resulted in giraffes being able to feed on leaves that others can’t reach and this gives them a competitive advantage and those with long necks are able to survive to reproduce and pass on this characteristic to the successive generation,”

“Right,” Connor said as he continued. “And we can further break natural selection down into three types- Stabilizing selection occurs when the population stabilizes on a particular trait value and genetic diversity decreases in favor of that dominant and beneficial trait. Some animals ay large clutches of eggs or have many young in order to improve to odds of more surviving to adulthood. Directional selection happens when a single genetic trait is favored, causing any future mutations and changes to continuously shift in one direction. The pepper moth exercise we did in the previous class is an example of this sort of natural selection process. Ad finally there is diversifying selection which happens when extreme values for a trait are favored over the intermediate values. This type of selection often drives the development of subspecies traits such as fur color, size, and feeding habits.”

“So for the rest of class let’s think about these three types of natural selection and let’s see what other examples we can come up with” Connor said as he wrapped up the lecture. “So, who wants to get us started?”