Title: The Making of the Fittest
Author: Sean B CarrollPublisher: Quercus 2009 (First published 2008)Pages: 292ISBN: 978-1-84724-724-7
The book is divided into ten chapters, six of which describes the genetic theory and the science behind it. Carroll describes it as his six-course dinner. After this, the next two chapters are what he calls after-dinner conversations in which the arguments of creationists and intelligent designists are lampooned with clear and logical argument based on history of similar occurrences. It was the aim of the author to supply the reader with enough arguments which he can present in our own discussions which we may have to do in our lunch conversations or more probably, our children’s schools.
The second chapter presents a primer on the basic maths behind evolution. A branch of knowledge can’t be called proper science, if it is not represented in the language of science – mathematics! The facts given are very basic, but it clearly spells out the facts and in the end, we can be pretty assured that the chances and probabilities for genetic mutations and hence evolution to occur are not that remote as it is made out by the opponents of this theory. Since every base pair in the DNA sequence is copied one by one by a process which is not totally error-free, it results in a very small probability of having errors in one of the alphabets of the DNA code (A, T, C and G). Even this minor change may result in the production of fundamentally different proteins.
The third chapter starts with the science. The basics of evolution is like this. The genetic information of plants and animals are conveyed to the next generation in the DNA code inherited from parents. It looks like a double helix connected by base pairs which consist of two of the four above mentioned letters. When the DNA is copied to carry to the offspring, there occurs some times a flaw which causes a different letter to be copied. This is called a mutation which need not be bad in all cases. This variation is invariably present in every generation and if such a random variation is beneficial to the organism in natural selection or sexual selection, that trait is enhanced in subsequent generations and after considerable time, all members who don’t possess this variation might be wiped off. Variation, selection and time are the three components of evolution. The basic definitions are as as follows. Proteins are the molecules that do all the work in every organism – from carrying oxygen, to building tissue, to copying DNA for the next generation. The DNA of each species carries the specific instructions (in code) necessary for the building of these proteins. DNA is made of two strands of four distinct bases. The strands of DNA are held together by strong chemical bonds between pairs of bases that lie on opposite strands – A always pairs with T, C always pairs with G. Proteins themselves are made up of building blocks called amino acids. Each amino acid is encoded as a combination of three bases or a triplet (ACT, GAA etc.) in the DNA molecule. The chemical properties of these amino acids, when assembled into chains averaging about 400 amino acids in length, determine the unique activity of each protein. The length of DNA that codes for an individual protein is called a gene. (p 78-79).
Fourth chapter describes how new capabilities are evolved from the old which is explained with an apt example of the development of full colour vision in colobus monkeys of Africa. All monkeys in the old world possess colour vision whereas most of the new world monkeys have only a dichromatic vision in which shades of two primary colours will be seen. The colour of an object is the wavelength of light reflected by it and specific wavelengths activate visual pigments in our retinas which are made up of a protein, called an opsin. Humans have three different visual pigments, which are sensitive to short, medium and long wave lengths, specifically to 417 (blue), 530 (green) and 560 nm (red). Most other mammals have just two opsins and genes, while birds and fish have four or more. Some birds can see also in the UV range. The third colour gene in humans was made by an error in replicating one of the opsins, such that only three amino acid positions 180, 277 and 285 account for the 30 nm tuning difference between the red and green pigments. Most other mammals have colour blindness to distinguish between red and green. Sometimes, colour blindness appears in humans too, but in fact, natural selection is so strong in the wild that the percentage of monkeys with colour blindness is less than 0.1%, whereas it rises to 8% in humans where no natural selection operates. Trichromatic vision helps the colobus monkeys to select tender, red leaves which are more nutritious and they have developed ruminating to digest these leaves.
Similar to the development of new genes based on natural selection, some traits which are not used are weeded out because natural selection is blind to them. Some very old genes are found in the fish coelacanth (see picture) which has body features that link it to distant ancestors that lived 360 million years ago. It is thus called a ‘living fossil’. Present fish have shedded several of the genes of coelacanth, but they appear as non-functional DNA code in the present 
genome. The part was rendered non-functional by erroneous mutations in the sequence which was not rejected by selection. Mice have about 1400 olfactory (smell) genes in a genome of about 25,000 genes, but humans possess only 5 smell genes in their total of 25,000! However, humans do have erroneous copies of the mice smell genes and it is deduced that those genes are allowed to be fossilised when trichromatic vision developed in the ancestor of humans which made dependence on smell irrelevant. So, the paradigm of gene loss is, “Use it or Lose it”. This loss of genes is a valid argument against intelligent design. Evolution is not necessarily a progressive or additive process. Modern species are not better equipped than their ancestors, they are mostly just different. The pattern of gain and loss seen in species’ DNA are exactly what we should expect if natural selection acts only in the present, and not as an engineer or designer would. Natural selection cannot preserve what is not being used, and it cannot plan for the future.
genome. The part was rendered non-functional by erroneous mutations in the sequence which was not rejected by selection. Mice have about 1400 olfactory (smell) genes in a genome of about 25,000 genes, but humans possess only 5 smell genes in their total of 25,000! However, humans do have erroneous copies of the mice smell genes and it is deduced that those genes are allowed to be fossilised when trichromatic vision developed in the ancestor of humans which made dependence on smell irrelevant. So, the paradigm of gene loss is, “Use it or Lose it”. This loss of genes is a valid argument against intelligent design. Evolution is not necessarily a progressive or additive process. Modern species are not better equipped than their ancestors, they are mostly just different. The pattern of gain and loss seen in species’ DNA are exactly what we should expect if natural selection acts only in the present, and not as an engineer or designer would. Natural selection cannot preserve what is not being used, and it cannot plan for the future.
In the sixth chapter, several examples of evolution repeating itself if the environment demands it are given. This is demonstrated with the case of howler monkeys in South America which have trichromatic vision and live on a leaf diet. Evolution also creates a genetic arms race between the predator and prey, as shown in chapter 7. Humans and germs are ever in an arms race to overtake each other. There is a good percentage of people in Africa and India who suffer from ‘sickle-cell anemia’ which is a genetic disease in which the shape of the red blood cells are changed to the form of a sickle instead of round. However, this contributes resistance to malaria and hence sometimes favourably selected. Germs also evolve to resist drugs faster than we can imagine. The eighth chapter describes how complex structures such as the eye evolved in animals. This was argued to be one of the clinching cases of creationism. It is seen than activation of a gene called Pax-6 causes eye tissue to develop. Researchers have successfully created eyes on the feet of fruit flies in this way. Such activation is done by molecular switches present in the genome near protein coding sequences.
The final chapter arms us with arguments in favour of evolution which crushes the back of creationists and intelligent designers. Stubborn refusal and ideological differences to accept truth have caused people and nations to spurn progress. Two examples are given which include Lysenko and chiropractors. Trofim Denisovich Lysenko, a peasant with a meager education, rose to become a deputy of the USSR Supreme Soviet and director of the Genetics Institute of USSR. He refused to accept the reality of DNA and put forward outlandish and flawed hypotheses of his own to design new experiments which resulted in utter failure. Since he was close to Stalin and other prominent party bosses, he silenced all his opponents, sending many to the firing squad. This refusal crushed Russian biological research for a long time until Stalin was dead. Chiropractors, on the other hand, is a group of people practising alternate medicine in several parts of the world. They theorise that all diseases are primarily neurological in origin, and caused by the pinching of nerves by misaligned vertebrae. They are against germ theory and refuse to vaccinate.
There are six arguments or tactics used against evolution
1. Doubt the science: One often encounters blanket statements, such as “virtually no scientific evidence for evolution exists”. Such conclusions are often presented as logical conclusions to a variety of arguments refuting elements of evolutionary science. Paleontology has identified many examples of fossils with characteristics that are intermediate between those of different groups. Even Pope John Paul II had changed his tone when he remarked about evolution in a 1996 statement published in L’Osservatore Romano:
“fresh knowledge has led to the recognition that evolution is more than a hypothesis. It is indeed remarkable that this theory has been progressively accepted by researchers, following a series of discoveries in various fields of knowledge. The convergence, neither sought, nor fabricated, of the results of work that was conducted independently is in itself a significant argument in favour of this theory”.
2. Question the motives and integrity of scientists: At the heart of much opposition is the assertion that evolutionary science is motivated by an atheistic philosophy. Often opponents will equate them to all evil.
3. Magnify disagreements among scientists, and cite gadflies as authorities: There has been honest differences of opinion among researchers regarding some of the mechanisms of evolution. This is blown out of all proportions and is presented as disagreement. Also, there are some reputation seeking people among scientists who openly oppose scientific ideas. Getting a doctoral degree and making negative arguments are relatively easy – making new, verifiable discoveries is an altogether different matter. The deniers specialise in rhetoric and the mining of quotes, not in laboratory research.
4. Exaggerate potential harm: Opponents of evolution perceive great danger in evolutionary principles and lay much blame for society’s difficulties on the influence of ‘Darwinism’ in modern culture. He is also blamed for Soviet-style communism. By inflating evolutionary science into a political philosophy, they are discrediting the science. This hijacking is termed by Steve Jones as, “Evolution is a political sofa that molds itself to the buttocks of the last to sit upon it”.
5. Appeal to personal freedom: The teaching of evolution in public schools is frequently viewed as an assault upon the religious freedom of those who oppose it. Such arguments are rejected by US federal courts, however.
6. Acceptance repudiates key philosophy: The ultimate source of the conflict over evolutionary science is the same that was seen over genetics in the erstwhile Soviet Union and vaccination in the chiropractic community. It is viewed at odds with matters of faith that are not open to scientific evidence. As stated by the organization Answers in Genesis, “the real issue is the authority of the Bible as a trustworthy revelation from God, and hence the integrity of its Gospel message”. There are three arguments put forth by them.
1. Evolution must be rejected because it denies the Bible
2. Evolution must be rejected because it denies God
3. Evolution must be rejected because it denies salvation.
2. Evolution must be rejected because it denies God
3. Evolution must be rejected because it denies salvation.
A commendable book by all means. Genetics and study of DNA had not developed when Darwin was alive and he was ignorant of the mechanisms by which his variations were finding place among offsprings. Even then, it is astonishing to see that every further step in knowledge further advances the theory of evolution further, instead of negating it.
Overall rating: 4 Star
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