What Evolution Is, and What It Is Not

Introduction

Evolution is identified as the gradual change in a species that abandons the simpler form to create a more complex form. As a result, the change process occurs over numerous generations of the biological population. The process of evolutionary diversity has been identified as a critical factor in the rise of diverse biological organization present in molecules, species and organisms. The theory of evolutionary thought is believed to have date to pre-Socratic philosophers in ancient Greece. However, it is the publication of the book “ On the Origin of Species ” by Charles Darwin that serves as the formulation of a scientific foundation of evolution by natural selection. The book “Why Evolution Is True” by Jerry Coyne features a great deal of evidence on the authenticity of the Darwinian theory of evolution. Therefore, through the study of major themes of each chapter the following paper will identify what evolution is and what it is not.

Definition

Coyne (2009) begins with a clear definition of evolution. Hereby, evolution is seen as the process of life on earth gradually beginning from a single species that replicates molecule which is believed to be 3.5 billion years ago. This species would then branch out over time in creating many more species that are both new and diverse. The mechanism for evolutionary change is referred to as natural selection. The definition identifies six concepts that include “evolution, gradualism, speciation, common ancestry, natural selection and nonselective mechanisms of evolutionary change” (Coyne, 2009). The evolutionary theory in itself is identified as a philosophical perspective whereby an idea has been created through research to identify the natural processes living organisms have undertaken to change from primitive to complex.

The next concept is gradualism that identifies the need for many generations to pass to ensure substantial evolutionary change takes place. In this case, a theological perspective is provoked where the theory challenges the creationism theory that identifies biblical scriptures as having the clear creation process of organisms (Carroll, 2006). The next two tenets are believed to form the sociological perspective of evolution. Speciation identifies the evolution that is evident among different species that cannot change genes. However, the idea of common ancestry indicates the close relationship of different species that can be tied to a single primary ancestor as seen by DNA sequences and fossils. The idea of natural selection serves as the next tenet whereby deleterious mutations in an organism are weeded out to ensure its survival. This is a scientific perspective where fossils indicate features that ensured their inability to survive. The final tenet is the idea that alternative processes have the ability to engineer evolutionary change. As a result of the evidences gathered on the theory, the author concludes that it is indeed true.

Written in the Rocks

The second chapter features an extensive theme that points out the need to study earth and rocks as a source of information for the numerous species that have existed a long time before us. Charles Darwin is quoted when he identifies the crust of the earth as a natural museum. However, the natural collection these species have been done at remote intervals of time (Coyne, 2009). These collections have been identified through the discovery of fossils that have been mentioned since the ancient eras such as that of the great Greek philosopher Aristotle. The fossil of the Protoceratops identifies a creature that led to mythical beliefs of the griffin among the ancient Greek society.

As Aristotle discusses the fossils, the theory of evolution is identified to have a close link with philosophical perspectives. It is identified that through active research of the earth’s crust one is able to derive the processes that are involved in the formation of the present species of organisms (Carroll, 2012). This may be identified as the scientific perspective whereby through multiple studies with similar findings a theory is referred to as “true”. The Tiktaalik roseae has been identified as one of the fossil species that has shown a clear association between fish and amphibians. The record kept on the discovery of a fossil and its year of living indicates how various animals have transitioned to others. The fossil record of reptiles with legs appears before that of snakes identifying that snakes evolved from lizards.

Remnants: Vestiges, Embryos and Bad Design

The author identifies the times in history when paper had not been discovered. Hereby, the writers of this medieval era would use palimpsests which are sheets of dried animal skins that had previously been used by other writers. In the same way, Coyne (2009) identifies the body of organisms as palimpsests of evolutionary history. The vestiges are the feature present in a species that was an adaptation among its ancestors but has lost its use completely. This is a scientific explanation of the evolutionary process where multiple organisms have been identified to possess features that they do not use completely. Atavisms and dead genes demonstrate the idea of common ancestry among the current organism species that is a key factor in the evolutionary process.

In this chapter, the author identifies that living organisms have presented multiple features that have demonstrated the philosophical and sociological aspects. Philosophical aspects have been presented in the evolution of man to increase in size of head and elimination of the tail to become an intelligent being. Sociological aspects are presented by the general features of similarity between two living things that identify their close association in evolutionary history (Pievani, 2014). Through the idea of bad design theological aspects are identified where the normalcy of an organism to fit into its environment has been identified as an illusion (Steinfels, 2005). Hereby, if organisms were built from scratch they would not have the various imperfections. As a result, this is clearly a process of evolution where imperfection is expected.

The Geography of Life

The next chapter looks into evidences of evolution as a means of explaining their distribution across the world. From a scientific approach, bio-geographic evidence has helped identify the numerous distributions of the different organism species as an explanation to refute the claims of creationists. The continental drift and molecular taxonomy have been major changes that have taken place since the discovery of the evolution theory. These developments have been an effective means of bringing an understanding of the various causes of distribution among the different species of the world (Coyne, 2009). The main concern is usually why species of similar features are found in two different geographical locations. 

Convergent theory has been identified as a theoretical explanation of why different species of an animal have similar features in different locations. This theory identifies that these animals are presented with similar environmental pressures that have prompted them to evolve and gain some adaptations that make them look and behave in the same way despite no relation (Coyne, 2009). The theory clearly ascribes three tenets of evolutionary theory natural selection, common ancestry and speciation. Through the study of this chapter sociological aspects are indicated where the behavioral response of an animal is identified in regard to its environment. The distribution of life on earth is a clear indicator of chance and lawfulness (Coyne, 2009).

The Engine of Evolution

The following chapter further describes the process of selection as a significant impact that leads to evolution. In this case, the mechanism is imposed on the species from inside where the genes that produce better adaptations begin to occur more frequently over time. The process of natural selection is a major cause for evolution to occur. However, there are three factors that promote the process of natural selection (Coyne, 2009). The first is the population being a variable, the second identifies that some of the variation has been achieved through changes in genetic formation called heritability and the third factor shows variation may affect a parent species’ probability of leaving offspring. As a result, the process of selection is seen as random and lawful. 

The chapter clearly describes natural as a process of evolution where mutations occur within a species. The random occurrence of these mutations indicates that the genetic responses may either be good or bad. Further, in the process of natural selection the animals are seen to experience a lawful change where good genes are kept while the bad ones are discarded..As a result, natural selection is an important part of evolution as it brings deeper understanding on preceding species and the traits they had before evolution occurred (Coyne, 2009). Though there are numerous forms of evolution, it is only through natural selection that adaptive selection occurs. 

How Sex Drives Evolution

The different traits that are present between a male and a female species have been identified as factors that drive the occurrence of evolution. It is important to note that these different factors are known as sexual dimorphisms. This comes from the Greek word meaning “two forms”. As a result, it is noted that survival is not the main currency of selection reproduction. Sexual selection will therefore come by in two forms where male species engage in direct competition for the females and the second is a case where the female species chooses the most suitable mate (Coyne, 2009). The males will be seen competing with each other in each case of sexual selection. 

Sexual selection presents an instance where sociological aspects are evident in the evolutionary process. This is seen where behavior animals during mating season is explained. Male peacocks will be seen to demonstrate their beautiful feathers in the presence of the females as a chance of becoming the most suitable mate for the mating season (Coyne, 2009). Human beings are also seen to present similar animalistic traits of behavior where the men will be seen to woo a woman as a means of gaining her affection for future procreation. Direct investment is seen as the cause for the difference between males and females. The eggs of the female are expensive and fewer in number whereas the sperm is cheap and in multiple numbers. The sensory-biased models also explain the how females get to choose their mate as they have preexisting biases in the nervous system that was created through natural selection.

The Origin of Species

The following chapter focuses on the distinguishing characteristics in nature as an objective fact. Organisms that reproduce sexually are identified into a discrete cluster known as species. The process of speciation is identified as a major cause for the biodiversity that is present in the world. Hereby, if it did not occur, there would only be one single descendant of the same species. In this regard, the species are seen to be distinct not only in how they look but also in the barriers created that prevent interbreeding (Coyne, 2009). The species can therefore be referred to as the evolutionary community as they are the thing that evolves. Therefore, explaining the evolution of reproductive barriers will help identify the origin of a species. 

A single species is seen to experience the evolution of sexual reproductive barriers that will lead to its significant split. The by-products of natural or sexual selection take action on the species resulting in genetically separated populations to evolve in two different directions. However, it is noted that species do not arise to fill up a niche in nature rather, they are evolutionary accidents. Through historical reconstruction, it is possible to identify the processes that led to re rise of a species. The research can help identify numerous testable predictions that can lead to evidence of the origin of a species.

What About US

Evolution has also been a critical factor in the description of the origin of man. It is evident that human beings arose from apes. The chimpanzee has been identified as the closest cousin of human species. The Australopithecus africanus serves as the first fossil to be identified as a distinct ancestor of the modern human species (Steinfels, 2005). The species is seen to have been alive several million years ago. The researchers have been unable to identify the missing link between humans and apes. However, it is possible to find the evolutionary cousins. Through the photographs provided in this chapter clearly indicates the presence of a common ancestor between human beings and chimpanzees. Environment and climate had a substantial impact in the occurrence of the first homonin trait to evolve which is bipedality. The differences between chimpanzees and humans are both in physiology and anatomy. 

Evolution Redux

The book pens off by stating the high levels of ambiguity that is experienced among members of society concerning evolutionary biology. There has been vast evidence both in real time and fossil record that has demonstrated evolution and the formation of a new species. There have been cases of transitional forms between whales and land animals as the members of the large groups. In each day, hundreds of living organisms have been tested as a means of adding onto the myriad of scientific literature on the same. These studies have unearthed fossils, tested DNA sequences and dissect organ systems all providing evidence of evolution that species evolved from a common ancestor.

Conclusion

The book “Why Evolution Is True” by Jerry Coyne seeks to present numerous arguments on the issue similar to its title. The book takes a systematic approach of presenting argument by first establishing a definition that can be used to understand the process of evolution. The key tenets of evolution are discussed in the following six chapters including evolution, gradualism, speciation, common ancestry, natural selection and non selective mechanism of evolutionary change. Further, the impact of evolution on human beings is discussed to prove the truth in the theory. 

References

Carroll, S. B. (2006) The Making of the Fittest: DNA & The Ultimate Forensic Record of Evolution . New York: W. W. Norton & Company, Inc.

Carroll, S. B. (2012) Endless Forms Most Beautiful: The New Science of Evo Devo and the Making of the Animal Kingdom . New York: W. W. Norton & Company, Inc.

Coyne, J. A. (2009) Why Evolution Is True . Oxford: Oxford University Press.

Pievani, T. (2014) " Individuals and groups in evolution: Darwinian pluralism and the multilevel selection debate.” Journal of Biosciences , Vol. 39 Issue 2: 319-325.

Steinfels, P. (2005) A Catholic Professor on Evolution and Theology: To Understand One, It Helps to Understand the Other . New York Times, Online. Retrieved from http://www.nytimes.com/2005/08/20/us/a-catholic-professor-on-evolution-and-theology-to-understand-one-it-helps-to-understand-the-other.html