BIOL 1122 Written assignment UNIT 1 PDF

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But I tell you, love your enemies and pray for those who persecute you Matthew 5:44...

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Written Assignment Unit 1 University of the People BIOL 1122 Matt Badtke 04/10/2021

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Outline at least three types of evidence which support the theory of evolution, providing specific examples for each. Ensure you include at least one modern example of observed natural selection and indicate the selective pressure that may have led to it. The three types of evidence that I chose that support the theory of evolution is anatomy, biogeography, and fossils. When we look at anatomy to support the theory of evolution, we ultimately end up breaking that down into subcategories of various features. Such features are known as homologous and analogous. The homologous features are features that are said to be shared by different organisms through a common ancestor. “To give one classic example, the forelimbs of whales, humans, birds, and dogs look pretty different on the outside. That's because they're adapted to function in different environments. However, if you look at the bone structure of the forelimbs, you'll find that the pattern of bones is very similar across species. It's unlikely that such similar structures would have evolved independently in each species, and more likely that the basic layout of bones was already present in a common ancestor of whales, humans, dogs, and birds.” (Evidence for evolution (article). (n.d.). Khan Academy). On the contrary, analogous features are similar features that developed in not-so-similar organisms due to their environment being the same, basically forcing them to adapt and add on those specific

features. (National Geographic Society. (2019, June 5). Theory of evolution). Such traits are traced down in various ways, and the anatomy aspect helps draw parallels from one organism to another. Another type of evidence that helps support the theory of evolution is biogeography. The main concept and point that supports this evidence factor is the fact that when there was one big continent on Earth around 200 million years ago (according to the theory of evolution), the organisms that developed on it before it broke up into smaller landmasses are more widespread and tend to be found throughout the world. On the contrary, organisms that were developed and found later on, already on such “broken” modern landmasses (where we live today), have more of a tendency to be specific to a region and not found anywhere else. “For instance, there are unique groups of plants and animals on northern and southern continents that can be traced to the split of Pangaea into two supercontinents (Laurasia in the north, Gondwana in the south).” (Evidence for evolution (article). (n.d.). Khan Academy). To simply put it, when studying remains of various organisms, the area of their origin plays a big role in determining what region they were from and how/why they developed in accordance with their environment. The third and probably most convincing support for the theory of evolution for a lot of people are fossils. The fact that it’s something you can see for yourself in museums, touch, it gives confidence to many scientists and researchers in this field. Although the fossils of animals are almost never found, or if found, they’re not completely in-tact, nonetheless, scientists are always ecstatic over a find. One way or another, it’s something that can be researched, and information can be derived from it. A lot of the time, fossils are derived from strata (rock) which serves as a sort of timeline; scientists can tell how

old it is, the upper part being younger and the lower part older. There’s also radiometric dating, where radioactive decay can be measured and the age more or less established. One modern example concerning natural selection would be bed bugs. As of today, they did in fact develop actual physical changes, operating at night while we sleep and developing longer legs to be able to move around much quicker. Their choosing to live in mattresses makes it difficult to find them through the stuffing, and they are a serious problem for any city dweller. (Brodwin, E. (2015, March 10)).

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Briefly, describe some of the proposed mechanisms for evolution, include in your answer any factors that may have an impact on the process and comment on whether you believe that humans can influence this and why.

Some of the proposed mechanisms for evolution are gene flow, mutation, and natural selection. One of the most prominent mechanisms, the most well-known, mutation, is something that an organism undergoes under environmental pressure over long periods of time, generation to generation. The changes might be subtle at first, but 10 generations later you might see webbed feet on an organism whose ancestors didn’t sport such a configuration. Another well known mechanism is natural selection. This is the concept of survival of the fittest, and it smoothly transitions from the mutation mechanism we mentioned before. If an organism has mutated and is equipped a lot better for its environment, then the process of natural selection will turn out well for it. On the contrary, if a beneficial mutation didn’t happen, the organism will most likely have a hard time surviving and reproducing. (Mechanisms of evolution (article). (n.d.). Khan Academy). Humans can without a doubt influence this process by doing things like

littering and polluting wildlife areas, forcing animals to adapt to that new ruined environment, or be forced to migrate to other areas, creating biogeographical differences.

References Than, K. (2018, February 27). What is Darwin's theory of evolution? livescience.com. https://www.livescience.com/474-controversy-evolutionworks.html National Geographic Society. (2019, June 5). Theory of evolution. https://www.nationalgeographic.org/encyclopedia/theory-evolution/ Evidence for evolution — New England complex systems institute. (n.d.). New England Complex Systems Institute. https://necsi.edu/evidence-for-evolution Evidence for evolution (article). (n.d.). Khan Academy. https://www.khanacademy.org/science/biology/her/evolution-and-naturalselection/a/lines-of-evidence-for-evolution Brodwin, E. (2015, March 10). 12 examples of evolution happening right now. Business Insider. https://www.businessinsider.com/examples-of-evolution-happening-right-now2015-2 Mechanisms of evolution (article). (n.d.). Khan Academy. https://www.khanacademy.org/science/ap-biology/natural-selection/hardyweinberg-equilibrium/a/hardy-weinberg-mechanisms-of-evolution...