What Evolution is and Isn't (Term Paper Sample)

What evolution is and isn’t
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Institution
What evolution is and isn’t
Introduction
In recent times, "intelligent design”, creationism, and evolution have been at the center of heated debates. Most of the texts focus primarily on the biological side of evolution while others focus on fossil evidence. Jerry Coyne’s book Why Evolution is True is unique in this regard because it covers nearly all the bases in a clear, but enjoyable and moderately persuasive manner. Coyne clarifies common misconceptions regarding how the science works and refutes the use of the word "theory" by creationists. He also underlines the compelling overview of fossil evidence underpinning evolution, drawing from the most popular and recent examples. The ideas outlined in Coyne’s text are also underpinned by other works such as Your Inner Fish by Neil Shubin. Shubin, an anatomist, relies on fossils, genes, and embryos to reveal how human bodies are the legacy of reptiles, primates, and ancient fish. He shows that evolutionary theory, just like global warming, is not based on a single point, but a myriad of indicators and supporting points. Just like Coyne, Shubin dedicates a considerable portion of the book to fossil evidence supporting evolution. He shows a progression in anatomy from fins to one bone, two, and then lots of bones. This essay relies on Jerry A. Coyne and Neil Shubin’s texts to examine what evolution is and isn’t from a personal philosophical, theological, and sociological reflection standpoint.
Evolution, according to Jerry Coyne, is the series of genetic changes that a species undergoes over time. This definition means that a species may evolve into something entirely different from many generations. The foundation of these changes is the changes in the DNA. Coyne presents various arguments to show that evolution happened. One of the most powerful arguments that evolution happened is the presence of vestigial organs in the body and some elements of "bad design" in the anatomy of the human body. Coyne refers to vestigial organs as the "mute witnesses" of evolution. Coyne believes that the presence of "useless" organs in the human body suggests that these organs were once useful before. He believes that as living condition changed and internal changes happened the work that these organs were accustomed to conducting was no longer necessary. Coyne also explores examples of bad design such as human tails and whale hips and legs as well as other features and manifestations of "dead genes." (Coyne, 2009) Coyne is a neonatologist, but he does a good job of highlighting the strengths and limitations of fossil records, and how influential fossil evidence has become in indicating the actual course of evolution. Similarly, Anatomist Neil Shubin in his book Your Inner Fish highlights the fact that the presence of numerous fossils as evidence over the years supports the concept of evolution. His ideas are also largely based on the existence of fossil evidence to underpin evolution. He gives the classic as well as the lesser known examples of fossil evidence such as the Tiktaalik fossils that were discovered in 2004. I find the examples presented by Coyne and Shubin to be considerably compelling because they are underpinned by logic. Coyne and Shubin do not rely on isolated instances of fossil discoveries, but they have a series of examples that have been put together to show progression in the evolutionary changes in the human anatomy over thousands of years.
The second theme besides evolution as evidenced by fossil discoveries is the notion of a common ancestor or common descent. Coyne’s text supports the concept of common descent as explored by Neil Shubin. In the eighth chapter, Coyne shows that humans are related to members of the animal kingdom. He also shows that they evolved from "non-human ancestors" (Coyne, 2009). He provides evidence drawn from paleontology, human anatomy, and genetics, making a human connection with the animal kingdom undisputable. Prime examples of these connections are the great apes. These ideas are supported by Shubin’s text. Shubin shows a progression from true fins, to single bones, two bones, and eventually to many bones. He develops the idea of "fundamental design" in vertebrate land animals as well as marine mammals. He writes that the fins of most fish, such as the zebrafish have extensive fin webbing and numerous bones at the base. On the other hand, lungfish are interesting because like humans they have only one bone at the base of the appendage. Also, the human head is organized like those of extinct jawless fish. These similarities highlight a relationship. The Tiktaalik fossils act as the link between human anatomy and fish anatomy, pointing to the possibility of a common ancestor. Further, Shubin shows that the relationship between humans and fossil animals is not only underpinned by anatomy, but also by genes. Major parts of human genomes look and function like those of bacteria and worms. This evidence is compelling, but I believe that similarities do not necessarily point to common ancestors. From a theological standpoint, I would argue that these similarities point to the creator’s common way of thinking for different creatures. God, the creator, may have introduced these similarities to allow humans to relate and understand the members of the animal kingdom. I believe that the argument for a common ancestor is compelling, but not as compelling as that of evolution, or the gradual change in DNA in a species over time.
For me, the idea of the common ancestor is not fully convincing. Proponents of this theory fail to explain in a persuasive manner why the common ancestor underwent splitting, or speciation to produce many different organisms. How did this diversity arise from a single ancestral form? Coyne poses this question and proceeds to introduce splitting and speciation as credible explanations to this question. He says that modern reptiles such as lizards and snakes are different to modern birds and their dinosaur relatives because they are descendants of species that split into two different groups. While this explanation may seem logical in terms of the workings of splitting, there is no compelling effort to explain why splitting happened. Why would the common ancestral form split into different branches of species? The only explanation given is that different environments led to genetic and anatomic changes in organisms. However, this explanation is not detailed or persuasive. As such, opponents of evolution would comment that the aspect of a common ancestral form is not convincing. The evidence that exists only supports evolu...