Chapter 9 Essay Questions
  1. When laws making the teaching of evolution a crime were first enacted, a teacher named Scopes in a small town in Tennessee became the focus of a famous trial enforcing that law, with Clarence Darrow for the defense and William Jennings Bryant for the prosecution. What was the outcome of the trial?
  2. One of the strongest lines of evidence supporting Darwin's contention that micro evolutionary change (that is, adaptation) occurs within populations is the study of peppered moths in England. Describe a specific experiment that has provided clear evidence that natural selection is responsible for the changes insect collectors had noted in British peppered moth populations.
  3. There are two very direct lines of evidence that macroevolution has occurred. One of them is the pattern of molecular differences in the DNA of organisms -- the more distantly related they are, the more their DNA is different. What is the other direct line of evidence, and how does it provide direct evidence of macroevolution?
  4. Give one example of selection being an important evolutionary force.
  5. Imagine a large population of jaguars in the Amazon rain forest (at Hardy Weinberg equilibrium). Within this population the frequency of a recessive allele for albinism is 0.16 (that is, 16%). What would be the expected frequency of jaguars in this population that carry at least one copy of the albinism allele?
  6. Creationists have often pointed out that life could not have evolved spontaneously, whatever the results of the Miller-Urey experiment, because amino acids cannot spontaneously join together to form peptide chains in water? Are they right? Why? How might an evolutionist respond to this objection?
  7. After graduation, you and nine friends build a raft, sail to a deserted island, and start a new population, totally isolated from the world. Two of your friends carry (that is, are heterozygous for) the recessive cf allele, which in homozygotes causes cystic fibrosis. Assuming that the frequency of this allele does not change as the population grows, what will be the instance of cystic fibrosis on your island? you? (b) how is a fish gene being used to improve tomatoes?
  8. Critics of evolution often focus on the Miller-Urey experiment. Describe this experiment, and outline one serious objection raised by creationists to interpreting the results of this experiment as support for a theory that life arose on earth spontaneously.
  9. Outline what you regard as the best argument against evolution (warning: this question is not a gift -- do a good job, presenting as good a case as is practical).
  10. Imagine that you were investigating turtles on a small family of islands in the Pacific, and wished to determine how many of the turtles were heterozygous for a rare turtle hemoglobin allele, allele t. Individuals homozygous for allele t have blue blood, giving their faces a distinctive blue color. Of 1264 turtles collected by you on the islands, 67 have blue faces. What proportion of the islands' turtles would be expected to be heterozygous for the t allele (assuming, of course, that the population is large enough to avoid drift, and is not subject to inbreeding or selection for or against the t allele)?
  11. What evidence in favor of evolution by natural selection was produced by Herman Bumpus in Providence RI in 1901?
  12. Why does an individual heterozygous for the sickle cell hemoglobin allele not died of the disorder?
  13. Sickle cell anemia is one of the best-understood of human genetic disorders. (a) If the "sickle cell" mutation of the hemoglobin gene confers immunity to malaria, why is its incidence in Central Africa less than 50%, when malaria will kill over 1 million people there this year? Why not 100%? (b) Why does an individual heterozygous for the sickle cell hemoglobin allele not died of the disorder?
  14. In the film God, Darwin, and the Dinosaurs, A high school teacher and his student are seen walking in a river in Texas. What are they looking at?
  15. Imagine a large population of jaguars in the Amazon rain forest (at Hardy-Weinberg equilibrium). Within this population the frequency of a recessive allele for albinism is 0.2 (that is, 20%). What would be the expected frequency of jaguars in this population that carry at least one copy of the albinism allele?
  16. The second law of thermodynamics states that a random process cannot create order. Discuss whether the origin of life by random events violates the second law of thermodynamics.
  17. Creationists often argue that evolution cannot be a valid theory because it violates the second law of thermodynamics. What is wrong with their contention?
  18. Creationists are fond of pointing out inconsistencies in the data and methodologies employed by evolutionists. Thus with great glee they point out that if you go buy a living oyster at the market, grind it all up, and radio-date it, you will obtain a date indicating that the oyster was over 3000 years old! Explain this apparent inconsistency.
  19. Most biologists tentatively accept the hypothesis that life first arose spontaneously in some sort of "primordial soup", as Oparin suggested in 1920. Some have protested, however, that proteins cannot have formed spontaneously from amino acids in the primitive seas. What is the basis of their objection, is it valid, and where does that leave the idea of spontaneous origin?
  20. 800 miles to the north of the Galapagos Islands is a single island, Cocos Island, about the same distance from the South American mainland (approximately 1000 km). On this island is a single species of Darwin's finch, clearly related to the 13 species of Darwin's finches that populated the Galapagos. Why do you suppose 13 different species evolved on the Galapagos Islands, and only one on Cocos Island?