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Making of the Fittest Analysis
Fossils have been used over the years to provide a glimpse of historical life that once existed. Genes on the other hand, are used to prove the process of evolution indeed occurs. This book gives significant new evidence of evolution provided in the DNA. It reviews new examples from a sequence of DNA that one time coded for genes that seized to be used. It focuses on the remains of ancestral lives to bring forth evolutionary changes. It further uses forensic evidences of evolution to reveal new evidence of characteristics and capabilities that were abandoned as species embraced new lifestyles. This book refutes the contemporary understanding that evolution is a completely random process. It reveals that there exist order and complexity of nature that compels this process to occur outside the context of random process.
The first theme that is evident is that some genes are immortal while others are not. Any living organism has a set of genes adapted to the domain of life. These living organisms could be fungi or bacteria. These set of genes usually encode functions dedicated to the decoding of the genetic material. These functions have been in existence for a billion years before (Carrol 27). It is thus clear that they are preserved by the natural selection processes. The codes noted in these organisms are shared. The main reason for preservation is essential for the function that these organisms would not survive without them. They are thus protected from any major changes a role that is not guaranteed in other types of genes. These genes are very useful in assisting to trace the past history of the organisms.
The second theme is the fossil genes that reveal they were functional for the ancestral species at one time. These genes over the years seized to be functional and as a result decayed and only created DNA records. It is important to note that there are evidences that show that such genes were very essential to the lives of the host ancestor. While mutations happen, some are known to leave negative impacts to the host. When they have no negative impact to the host, they tend to continue existing and are tolerated. This pushes the host specie to begin changing their lifestyles (Carrol 34). A perfect example given in the book is an animal that starts living in caves as opposed to the host ancestor that lived in the open air. This changes the selective conditions and certain traits have started developing. Example of traits that change is the body pigmentation and the vision. Such traits are no longer preserved because there is no evident pressure to preserve them. As a result the genes which are responsible for encoding such traits decay and are thus the fossil genes.
The third major theme is that all genes are generally vulnerable to mutations. It is clear that some mutations are not successful to genes that are specifically responsible in carrying out some functions. This is because they may compromise those functions and make the host species difficult to survive. If mutations happen to some species and there are no evident negative effects, mutation tends to pile up (Carrol 57). An example given in the book is the fact that genes in host species who have shifted their lifestyles and abandoned their former life, results to many broken pieces of DNA.
Comparison of DNA across different species has expanded knowledge about evolution. It is a common assumption when species share the same traits and same genetic sequence tend to share common ancestors. However, it has always emerged that there is also convergent evolution. In this the same traits and same genetic sequence are observed in species that existed in many millions of years apart (Carrol 89). This book concludes that the current species cannot be deemed better than the ancestral species. This is solely because of the natural selection process that is forced by many existing dynamics of life and it happens at that time that is essential for the species. In this regard it is clear that the process did not foresee the future, rather it happened in the present to help the species exist. There are many dynamics that force this natural selection process occurs. These may be changes in climate, earth or drifting of continents. The making of the fittest reveals that naturally species have to keep up with these changes over time.
Works Cited
Carrol, Sean. Making of the fittest. London: W.W. Norton and Company publishers. 2007, Print