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Table of Contents,Subject Discussed Addendum,Why an addendum 1. Chapter 11,11 3 Genetic Changes p 302 1,Mutations in Reproductive Cells p 302 1. Unit 5 Change Through Time Page 374 4,What is Evolution 5. Chapter 14 The History of Life Page 376, 14 1 The Record of Life Early History of the Earth p 377. The Fossil Record 5, Diversity in the Paleozoic p 385 Cambrian Explosion 6.
Life in the Mesozoic p 385 6,14 2 The Origin of Life p 388 7. Simple Organic Molecules Formed p 390 9,The Formation of Protocells p 391 11. The Evolution of Cells p 391 12,The Unbreakable Cycle 12. Chapter 15 The Theory of Evolution 12, 15 1 Natural Selection and the Evidence for Evolution Charles Darwin. and Natural Selection p 401 13,Darwin Explains Natural Selection p 403 13.
Structural Adaptations Arise Over Time p 405 13, Physiological Adaptations Can Develop Rapidly p 407 13. Other Evidence for Evolution p 408 13,Fossils p 408 14. Anatomy p 408 14,Embryology p 410 15,Biochemistry p 410 16. 15 2 Mechanisms of Evolution p 412 17,Changes in Genetic Equilibrium p 413 17. Natural Selection Acts on Variations p 415 17,Speciation Can Occur Quickly or Slowly P 419 17.
Patterns of Evolution p 420 18,Diversity in New Environments p 420 18. Chapter 16 Primate Evolution p 428,16 1 Primate Adaptation and Evolution p 428 18. 16 2 Human Ancestry P 438 18,Hominids p 438 18,Conclusions 19. Why an Addendum, An addendum is necessary because the authors have written the text around the idea that. evolution is an essential part of biology as is evidenced by the textbook statement on page 10 The. gradual accumulation of adaptations over time is evolution Clues to the way the present diversity of life. came about may be understood through the study of evolution It should be remembered that biology is. the study of living things It is not necessary to know an organism s origin to determine how it functions. internally and externally to how it relates to other organisms and to make predictions about other. organisms Origin of and similarity to other organisms while interesting is not necessary to understand. the detail functioning of a specific organism, The term evolution has more than one meaning which leads to many misunderstandings and.
unsupported conclusions Sometimes evolution means evidence for small scale changes within a species. which we can observe in the present day At other times claims of evolution are based upon. extrapolation and speculation about the deep past Read the first section on Chapter 14 of this addendum. page 5 for an understanding of the problem, This presentation will provide additional facts concerning evolution so that the student can clearly. see problems not answered by the theory of evolution This addendum presents facts that the student. should consider when judging the soundness of the theory of evolution. Should the student learn about the theory of evolution Definitely It is the dominant thinking of. today in the fields related to biology, This paper presents information only on the sections of the text where it is felt that additional. information would be helpful The information is presented as simply and briefly as possible since time. is crucial in the classroom Reference to the textbook will be necessary to completely understand this. 11 3 Genetic Changes Page 302,Mutations in Reproductive Cells Page 302. Add this paragraph at the end of this heading, The statements in this section are misleading in that they imply the phenomena is deceptively. simple Since mutations are supposedly the source of information for evolution it is mandatory to clearly. understand exactly what they are and what they are not Recognize that the definition concerns changes. in genetic information but that meaningful coherent information must be added to the DNA in order to. build complexity in organisms The question to keep in mind is Does the mutation actually increase. the information contained in the DNA or decrease it An increase in information is necessary to. claim that microorganisms eventually evolved into higher organisms like humans It is essential that this. need for information be understood and that mutations do not increase the genetic information. The rest of section 11 3 discusses different mutation mechanisms and forces that cause changes in. genes and therefore changes in organisms at the species level It must be recognized that just because. mutational changes do occur at the species level this does not imply or prove that all organisms descended. from a common ancestor The textbook does not discuss some of the factors that give the reader an. understanding of how difficult speciation is and the fact that it cannot explain the phenomena of. molecules to man or even amoeba to man evolution macro evolution First of all it must be. remembered that the DNA in a living organism contains the complete information necessary to form an. identical organism including the instructions of how to make a reader for its own code system The. amount of information stored in the DNA is staggering Second the amount of information stored in the. DNA of man is 4166 times more than that of the H 39 Mycoplasma one of the smallest bacteria now. called a mollicute 1 To put this in perspective the mollicute H 39 mycoplasma DNA 768 000 base. pairs 2 has the amount of information contained in the first 157 pages p 131 of this text if every page. written were covered by nothing but print with no spaces pictures graphs or headings similar to this type. page The size of the pages would be the same as in the glossary The information content in the DNA of. man 3 2 billion base pairs 3 is the same as 554 books like this text with nothing but text on the pages as. just described Some might argue that the above numbers are highly exaggerated because of what some. call junk DNA but it is now known that the so called junk DNA is not junk It is made up of introns. promoters terminators and telomeres 4 which are functional parts of the DNA A major question is where. did all of this additional information come from by random chance happenings to fill the 553 7 8. additional books, To understand the problem consider the following There is no known mutational mechanism.
that will increase the information content of DNA in a meaningful manner In other words transposons. point and frameshift mutations duplication errors jumping genes extra chromosomes do not add. meaningful information to the DNA Viral or bacterial invasion may add information but it will not be. meaningful Think about this problem with respect to this textbook Does mixing sentences letters. paragraphs errors in copying mixing up chapters or adding two or more identical chapters add. information The textbook may contain more pages but does it contain more information A chapter or. sentences from another book may be added so that there is more information but is it meaningful. information Is it likely to contribute to the sense of the original book It is inconceivable that. meaningful information can be added to accomplish the bacteria to man requirement of macro evolution. by random chance happenings It should be recognized that natural selection may decrease the. information in DNA but it cannot increase it, It is hypothesized that these changes in species ultimately lead to changes at the genus level the. family level and on up to the kingdom level see Section 17 1 page 459 of the text The great. complexity and preciseness found in the DNA and the tremendous increases in DNA information content. necessary to evolve from amoeba to man make the hypothesis unlikely When duplication errors. favorable mutatiions rates and the time necessary to establish a trait are considered this becomes apparent. Think Critically It has been discovered that the largest bacteria Epulopiscium fishelsoni has 85 000. copies of one of its genes and contains approximately 25 times as much DNA as a human cell 5 Does this. confirm the need for added DNA to be meaningful, The following is not considered lecture material and may be beyond the level of the text It is included for the teacher. It is known that duplication replication errors are extremely rare as the authors state The. textbook Biology The Dynamics of Life by Biggs Kapicka and Lundgren Glencoe 1995 further. complicates the problem when it makes the following statements Sometimes there is no effect on an. organism but often mistakes in DNA can cause serious consequences for individual organisms p 324. This textbook s authors agree on page 414 Sometimes the errors caused by point mutations don t interfere. with protein function but often the effect is disastrous p 325 Proteins that are produced as a result. of frameshift mutations seldom function properly p 325 Few chromosome mutations are passed on. to the next generation because the zygote several cells beyond conception usually dies p 326. Mutations often result in sterility or the lack of normal development in an organism p 328 Other. authors comment that only about one in 1000 mutations might be beneficial 6 Generally it takes about. 5 mutations to make a significant physical change in an organism 6 Note that this does not mean a new. species has been formed Many more than five mutations at a time have been caused on fruit flies. Drosophila melanogaster with only a deformed fruit fly as a result Dodson proposes that it takes over. 300 000 generations for a slightly beneficial recessive gene to increase in frequency from 1 in 1 000 000. to 2 in 1 000 000 7 It must also be remembered that a mutation in any cell other than the. reproducing cell does not have any influence on succeeding generations When all of these. probabilities are combined the question must be asked How can macro evolution occur from processes. that produce many more negative results than positive results. The previous paragraph reads so easily that most people do not realize that these apparently. simple statements mean that amoeba to man evolution is extremely unlikely To get an appreciation of. this let us examine these probabilities in more detail First consider the two statements that Many. random mutations are harmful only one in one thousand is beneficial and that it takes five. mutations to cause a significant change in an organism For the sake of discussion assume that. information content can be increased by mutations a false assumption as previously discussed The. question is Can progress be made up the evolutionary ladder of increasing complexity with odds that. give predominately negative results To illustrate the point use two pairs of dice to perform the. following experiment If a roll of the dice produces four ones assume this represents a favorable. mutation The odds of doing this are one in 1295 This is about the same as the odds mentioned above. for a beneficial mutation All other combinations on the dice represent unfavorable or neutral mutations. The textbook indicates that a majority of mutations are fatal so assume that any time four of any number. other than one comes up on the dice the organism dies instantly This means that only five out of the. 1296 far less than a majority mutations are considered to be instantly fatal Compared to the textbook. statements this is a very generous assumption The rest of the combinations represent unfavorable or. neutral mutations which do not normally kill the organism but if enough of these mutations do occur then. the organism will be weakened and die Assume twenty unfavorable or neutral mutations will kill the. organism so that if twenty rolls of the dice do not yield four ones or four of a kind then the organism dies. and the evolutionary process must be started over To keep track of your progress use the line below. The point A represents the original organism and point B represents the organism after 5 mutations. Remember that arriving at point B does not signify a new species. A x x x x B, Do you think that you can ever get to point B Try it You will quickly convince yourself that it is. essentially impossible The odds of getting to the first x is one in 1295 and for getting between points A. and B the odds are one in 3600 trillion if done in 5 consecutive dice rolls The odds of winning the. Power Ball Lottery are much better than this Remember that even if you do feel you could get to point B. this does not prove evolution because this has to happen many times to get a new species If twenty. mutations were necessary to have a new species there is only one chance in. 100 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 of having it. happen Winning the Power Ball Lottery six consecutive times has about the same odds When only. these two facts are considered it should be apparent that amoeba to man evolution is unlikely if not. impossible, Next let us reconsider the statement that This proofreading prevents most errors in DNA. replication Indeed only one error in 1 000 000 000 nucleotides typically occurs 8 It must also be. recognized that unless the mutation occurs in a sexually reproductive cell gamete that has been. fertilized the change in information will not be passed on The mutation must occur in an egg sperm. seed pollen etc Even in one of the smallest organisms like the H 39 mycoplasma a bacterium now. called a mollicute 1 the odds of this happening are unbelievably small Consider the following H 39. EVOLUTION ADDENDUM For Chapters 11 14 15 16 In the Textbook BIOLOGY The Dynamics of Life by Biggs Gregg Hagins Kapicka Lundgren Rillero

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