The Greatest Show on Earth by Richard Dawkins
1. Five Ah-Ha discoveries one finds in the books.
A wow discovery one finds in the book is that dogs are domesticated wolves, even more surprising is the fact that much of the initial domestication of the dog was self- domestication, mediated by natural, not artificial, selection (p. 35). That is to say, long before the so-called human domestication of dogs, natural selection had already transformed wolves into self-domesticated village dogs without any human intervention (p. 35). Only later did we adopt and transmogrify them, separately and comprehensively, into the kaleidoscope of breeds we see everywhere. More astounding still is the fact that tameness and phenotypical dissimilarities can still be breed in wild wolves or foxes. So some behaviors in animals are genetically determined. What does this say about our notions of sin or the assumptions behind the human justice systems Maybe some criminals are just biological freaks.
Human embryos have pharyngeal arches that are derived from ancestral gills another Ah-Ha evidence for the fact that our ancestors were once water-based. But this is not the only surprising find in the book. According to Dawkins, the fact that mammals, especially whales, dolphins, dungongs have the scaffolding to grow gills suggests that it should not be too difficult to do so. In other words, if we can establish, especially why water-based mammals have not re-evolved gills, then it is theoretically possible to correct the genetics mutations that prevent them from doing this. In effect, men can be re-reprogrammed to grow gills (p. 221). Why Because we already have the potential in our genes the only thing is that something switches off this potential at the five-week embryo stage.
Maybe we aught to research on this, because if we can only grow gills, then the next human abode can be the water it covers 80 of the world surface you know. What do you think
From the book, one realizes that if comparative evidence for evolution is combined with molecular evidence, then they not only reinforce each other something that Darwin could not have known but they provide a powerful on the theory of common ancestry. Here Dawkins had this to say,
Just as the vertebrate skeleton is invariant across all vertebrates while the individual bones differ, and just as the crustacean exoskeleton is invariant across all crustaceans while the individual tubes vary, so the DNA code is invariant across all living creatures, while the individual genes themselves vary (p 143).
A truly surprising fact, further one realizes that genetic code itself and the entire geneprotein system for running life, is universal. What varies is what is written in the code. But even here, the similarities are astounding. For instance Humans and chimpanzee share a 98 similarity. Wow Men and chimps are almost cousins in the literal sense.
The other striking discovery one finds in the book is that of the evolution of whales. In this regard, Dawkins presents a diagrammatic representation of the series of evidence of the gradual evolution of whales. From the gradual disappearance of the hind limbs, the transmogrification of the hind limps from walking legs to swimming fins and the flattening of the tail into flukes are among the changes demonstrated. See diagram below.
In this picture one is not only astounded at the fact that whales evolved from land animals but that this idea can be evidenced exhaustively.
An interesting fact presented in the book is that goose bumps are a non-functional relic of something that did a useful job in our long-dead. Indeed, the fact that we fluff non-existed hairs is a powerful indication for evolution that few notice. Thus next time you are goose pimpled, be sure to notice that that is your evidence of the fact that your ancestors were once hairy creatures (p 340).
2. How the information provided by Dr. Hawkins can enable one to respond to deniers of evolution.
The most prominent and persistent questions among evolution deniers will be treated in brief here.
On the evolution is only a theory retort.
Intellectual controversies can at times result from the conflicted use of the same word. The conflicted use of the word theory by proponents of evolution and its deniers is a case in point. Indeed, evolution deniers often stress the fact that evolution is only a theory giving the impression that a theory is merely a calculated guesswork, thus should not be taken seriously. This attempt to belittle evolution by creationist can easily be resolved if only we can understand, like Dawkins argues in the 1st chapter, that there are two meanings to the word. These include
Theory, Sense 1 a hypothesis that has been confirmed or established by observation or experiment, and is propounded or accepted as accounting for the known facts
Theory, Sense 2 A hypothesis proposed as an explanation hence, a mere hypothesis,
speculation, conjecture (p 5-16)
In there attack on evolution, creationists rely on the second definition while evolutionists rely on the first definition. Further, Dawkins argues that in actual sense, evolution is a fact it has really occurred- and the fact that organisms do change over time is accounted for by the theory of natural selection.
Thus, to the assertion that evolution is only a theory, one can assert that it is actually a fact.
On the age of the earth
Evolution deniers (especially creationists) especially creationists normally insists that the earth is young. And that the age of the earth can be inferred by a literal reading of the bible. Contrary to this opinion, scientists are now sure that the earth is very old and all the modern methods used to make this determination roughly agree. In his book, Dawkins lists the following methods Tree rings, radioactive clocks (potassiumargon dating, strontiumrubidium method, carbon dating, Thoriumlead etc) and stratigraphy etc (p. 107). Thus, to the question that the earth is young, one can assert without fear of doubt that it is billions of years old.
On the no one has observed evolution in nature question.
Contrary this assertion evolution has been observed in nature and in laboratories. According to Dawkins, evolution continues to take place before our very eyes. The following examples have demonstrated this The changing tusk weight in Ugandan elephants the case of the Lizard of Pod Mrcaru Lenski experiments with bacteria the case of Guppies and Lingula (p-112-117)
On the Missing links or the show me your intermediates question
Currently, there is massive evidence that show the existence of intermediate in humans, and since Darwins time, theres now an enormous amount of evidence about intermediates in human fossils and youve got various species of Australopithecus for example, and . . . then youve got Homo habilis (p. 185-189). The evidence for the evolution of whales from hippo-like ancestors is even more secure (See Fig 1.), while Archaeopteryx provides a bridge between amphibians and birds. One can go on ad neusum.
On the Ill Believe In Evolution When A Monkey Gives Birth To A Human Baby assertion
To this assertion the answer is simple according to Dawkins, human beings are not descended from monkeys, we only share a common ancestor. But even though human beings descended from simian-like ancestors, no animal can give birth to a new species
On the assertion that the theory of evolution contradicts the second law of thermodynamics.
The answer is this the question only reveals that the denier does not understand the meaning of the second law of thermodynamics. Infact, there is no contradiction. Why because of the sun.
3. How the Book has changed my thinking on the evolutionary process.
From the book, one can infer that controversies rarely concern what they purport to concern, instead, controversies often arise from the conflict of hidden assumption. The evolutionists creationist controversy is a case in point. One realizes that commitment to sanctions of authority (theological dogmas) and the hallowed rationalization of apriori philosophies is the biggest stumbling block to our understanding of evolution. Once these ideological commitments and other all too human perceptions are dropped, then one realizes that the role of natural selection in nature is as well evidenced as any other scientific fact. Its not a tottering nonsense built on numerous presuppositions. Thus, Ive understood the importance of evaluating the evidence for evolution critically and without any preconceptions. But this is not all reading the book has also corrected some of my previous misconceptions. For instance, I used to think that natural selection is goal-directed. Currently I find that this position is severely mistaken. Infact if one considers the fact natural selection is the differential survival of successful genes rather than alternative, less successful genes in gene pools (p 153) and that what selects is nature and that nature is itself subject to constant change, then one realizes that evolution is directionless and unpredictable. In all, the book has changed my thinking on evolution by correcting previous misconceptions and by engendering a greater appreciation of it.
4. How one can apply the information provided in the book in day to day interactions.
Generally, the information in this volume can be used to respond to everyday criticism of evolution that we always stumble on and to understand and appreciate nature in general. Further, Dawkins book can help in understanding the phenomenon of bacterial resistance to pharmacological agents, why drugs work better in combinations than as single agents and why we aught to comply with doctors prescriptions. If we think in terms of natural selection, then the all too common warning by doctors that we aught to take our doses in full make perfect sense (see section of Dr. Lenski experiment).
5. My evaluation of chapter 13.
In the last chapter, Dawkins deals with nearly all arguments presented in the earlier chapters, on chapter 12, he had this summary that, if the votaries of a benevolent, omniscient, omnipotent man-God cannot explain the pervasive occurrence of evil, with natural selection in the driving seat, all becomes clear, understandable and sensible (p. 399). Again, he presents a concise rendering as to the meaning of natural selection at the molecular level information that was scattered all over the book. Here he asserts that what distinguishes life and non-life is information not substance. Living organisms contain a vast amount of information. The information is digitally encoded in DNA.
DNA encoded information builds up over time, the special thing about DNA is that it survives not in its material self but in the form of an indefinite series of copies. Because DNA replication is not error free, new variants are generated and may have a better survival value than their predecessors, this signifies that the database of information encoding recipes for survival will improve as time goes by. Such improvements may present as better adopted physical structures and generally fitter Individuals (p 420). This fact, he asserts, like he insisted in chapter 2 and 10, can be modeled in computers. In addition, it must be pointed out that left ingrained within this genetic information is the evolutionary history of the organism. Phenotypical this is seen in the idea of near-indefinite modification of forms over eons of time, however modified an organism is, it will still retain impeccable traces of the original
However, while the chapter gives one a good inkling of what the book contains, its still my opinion that reading it cannot be a substitute to reading the entire book. Only then will we understand Dawkins claim that evolution is an incontrovertible fact appreciate its beauty, simplicity, and power and the fact that its within us, around us, and its workings are embedded both in the rock of ages and in the genetic code of organisms.
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