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i) The fossil record shows gradual changes , and also shows branching patterns of phylogeny. ii) Geology, Physics and Astronomy independently conclude that the earth is 4+ billion (=thousand million) years old.
iii) DNA base sequences (genomes) from different kinds of living animals and plants confirm the same phylogenetic trees as did the fossil records of these same groups. iv) Anatomical and embryological evidence each support the same phylogenetic trees as do the DNA base sequences.(for example: gill slits in early human embryos) v) Antibiotic resistance by germs (unfortunately!) evolves constantly by natural selection in favor of genes that produce resistance. (tuberculosis is one of many examples) vi) By means of selective breeding , you can deliberately "evolve" large changes in animals and plants. (examples include the different breeds of dogs, cabbage etc.)
vii) Evolution can be simulated inside computers , by
>> random "mutations" in duplicate programs >>> competition between these different programs
viii) Mendelian genetics eliminated the criticism that mutations would get "diluted".
ix) Within each person's body, during their lifetime, their immune system turns out to work by selection of random differences in the DNA that codes for the binding sites of antibody proteins. This is logically a form of natural selection.
This will be explained later in the course, and is extremely important medically. "Autoimmune diseases" like Lupus and MS result from failure to weed out cells with DNA for anti-self Let's vote on whether the following is an unfair analogy :
Suppose that someone were to announce: What might they mean by this?
a) That they don't believe running water will wash away soil? b) That they don't believe that the Grand Canyon was produced by water wearing away soil and rocks for millions of years? c) That millions of years of water wearing away rocks wouldn't produce canyons? (even in principle?) d) That the Grand Canyon was created recently to look as if it had been the result of millions of years of erosion , but really only the last few thousand years worth of wear was actually caused by erosion? And fossils were put in the rocks to trick us? Other analogies: Does the sun comes up in the morning because the earth rotates on an axis? Does the earth rotate because of inertia? Is the shape of the earth's orbit around the sun caused by the laws of gravity? A person might think that God causes these phenomena by means of the laws of physics . Another person might think that God causes these phenomena directly, and that the results only happen to be the same as would be predicted by the laws of gravity and inertia. Courses in physics and astronomy don't leave out the laws of gravity, to conform with this latter opinion. For a biology course to leave out evolution is equivalent to leaving gravity out of astronomy or physics courses. You don't have to believe Darwinian evolution, but you should understand what you are not believing, and also know what evidence supports it. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Historically, what have been serious arguments AGAINST Darwinian evolution?
1) Not enough time since the formation of the earth and stars. 2) Dilution of genetic differences. But Mendel's discoveries solved this problem. 3) Not enough genetic variation. Discovery of mutations also solved this problem. 4) "Piltdown man" missing link human fossils turned out to be a deliberate hoax. (this fooled people from 1913 to ~1953) But thousands of real human ancestral fossil skeletons have been found, that were not fakes.
5) Claims of evidence for Lamarckian evolution (inheritance of acquired properties)
> Kammerer's research in 1920s Vienna > Arthur Koestler's book "Case of the Midwife Toad"; 6) Difficulties of explaining separation (isolation) of species gene pools from each other. ("the Modern Synthesis" between genetics and evolution: 1930s)
7) What about "missing links" in the fossil record? ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Study Questions 1) In addition to biology, which other sciences have independent evidence that the earth is about four billion years old (four thousand million years)?
2) When they were first developed in the 1950s, antibiotics like penicillin were much more effective in curing people than they are now. Explain how this is an example of Darwinian evolution (by natural selection).
3) Suggest an explanation for the following: It has been noticed that fewer resistant bacteria evolve when patients are given heavier doses of an antibiotic, and when the patients continue to take their pills until they finish their prescribed doses (instead of stopping taking the antibiotic as soon as they feel well). **4) In Kansas medical schools, should the mechanism of development of antibiotic resistant bacteria be taught as "only a theory"? *5) Some of the mechanisms by which bacteria resist antibiotics are fairly simple, i.e. enzymes that destroy the key part of the penicillin molecule. Other mechanisms of resistance are fiendishly complex. Which would be more likely to result from "intelligent design", and (considering that people are often killed by germs that have developed antibiotic resistance), what would be the nature of the intelligence that does this designing? 6) The differences between breeds of dogs (great danes, cocker spaniels, etc.) resulted from processes that are similar to Darwinian evolution in what respects, but differ from Darwinian evolution in what other respects? 7) Could you argue either pro or con whether patterns of differences in amino acid sequences of proteins (like Rubisco) are or are not evidence in support of evolution? 8) If a biological structure or mechanism could only result from a combination of many independent mutations, many or all of which (by themselves) would produce no increase in the number of surviving offspring of an organism, then would Darwin predict that such a structure would be able to evolve? [Hint: No, but figure out why] 9) Did electric eels seem to be an example of this kind, in the sense that the ability of some fish to produce great voltages could not be explained by natural selection? [Hint: yes. But explain why?] 10) What is now believed to be the solution to this paradox? (of electric fish)
11) Suppose that some animals had wheels, structures that rotate around a fixed axis. Why would Darwinian evolution (apparently) not be able to explain the origin of wheels? (At least at the molecular level and not counting ATP synthases) 12( What is some embryological evidence in support of evolution? 13) Does this embryological evidence in itself specifically support natural selection as the cause of evolution? [Hint: not actually]
14) Antibodies are a special kind of protein by which our bodies defend us against germs. Antibody binding sites exactly fit molecules of the germs, thereby inactivating the germs. Compare this process to Darwinian evolution. *15) In what sense does vaccination against diseases work by Darwinian evolution of randomly mutating cells within the body?
*16) Why is it essential to have some mechanism that selectively kills or otherwise eliminates any antibody-producing cells in which mutations have resulted in antibodies that bind to any of the thousands of kinds of animal molecules? *17) Are these systems better or worse than evolving antibodies to different germs by some ancestors not dying of a disease, and other people of their generation dying of that disease? (Query: Is that how you previously thought that evolution of disease resistance occurred?) 18) What happens to a person who stops being able to produce new antibody producing cells?
19) Notice that this system of immunity depends on the combination of
b) selective growth and division of those cells in which these random genetic changes have produced antibodies that bind to germs c) selective elimination of cells that produce antibodies that fit normal body molecules
By themselves, each of these processes is either harmful or useless.
20) Assuming the existence of an "intelligent designer" (who manipulates evolution to produce combinations of genes that are impossible for Darwinian evolution to produce), then what two alternatives could be used? 21) People worry about eating organisms whose genes have been deliberately changed by molecular biology. If such a person also believes in "intelligent design", then what else should they worry about eating?
22) If humans evolved from less intelligent animals, could this have occurred by natural selection of differences in intelligence betwen individual ancestors that was not at least partly caused by differences in certain genes? 23) If you wanted to produce a more intelligent breed of dog, then how would you do it? 24) How is this similar to a "genetic screen" (that you learned about earlier in thie course)? 25) About what year did Darwin publish his theory of evolution? [Hint: 1859]
26) Until about when did biological researchers continue to debate whether the evidence proves that natural selection really is the cause of the existing variation in plants and animals?
27) Should creationists, or believers in intelligent design, submit their evidence to refereed journals?
28) Some of the discoveries that I have published in refereed journals have been included in only some textbooks, whereas most textbooks only mention other theories about the same subjects. Should each state legistlature vote to require textbooks to include theories published by professors at their state universities? 29) Would it have been logically possible for Darwinian evolution to have been disproven (or at least contradicted by) DNA base sequence data (from the various genome projects)? A good way to answer this question is to invent some pattern of base sequence similarities or differences that would not be expected to be possible, according to natural selection. 30) If variations in a given property of an organism do not result (even in part) from genetic differences, then can this property be improved by Darwinian evolution? Why not? 31) Which of the following abilities would be needed for molecules to begin life?
b) occasional random mutations in these molecular arrangements c) inheritance of these random mutations (in the sense that the copies may include the mutation (change)
32) What are some reasons to suppose that the first life on earth consisted of ribose phosphates?
33) If we were going to seed life onto other planets so that it would evolve into higher forms over the next few billion years, what would be the best seeds?
b) procaryotes c) consultants and lobbyists
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