Name Date Class CHAPTER 13 DIRECTED READING The Theory of Evolution Section 13-1: The Theory of Evolution by Natural Selection Darwin Proposed a Mechanism for Evolution Mark each statement below T if it is true or F if it is false. 1. There is clear evidence that species now on Earth evolved from organisms that are extinct. 2. Some individuals of a population or species are better suited to survive and to have more offspring. 3. Darwin proposed a mechanism explaining how evolution occurs. 4. The change in species over time is referred to as evolution. 5. Darwin learned that the plants and animals of Galápagos Islands and nearby South America resembled each other. Darwin Developed His Idea Read each question, and write your answer 6. What was the mechanism for evolution proposed by Jean Baptiste Lamarck? 7. What evidence did Darwin have that evolution took place? Darwin Sought a Reasonable Explanation for Evolution In the space provided, explain how the terms in each pair differ in meaning. 8. population, species 9. adaptation, natural selection Biology: Principles and Explorations Directed Reading Chapter 13 49
Darwin s Ideas Have Been Updated Complete each statement by underlining the correct term or phrase in the brackets. 10. Traits of individuals best suited to survive will become [more / less] common in each new generation. 11. [Genes / Natural selection] is (are) responsible for inherited traits. 12. [Natural selection / Genes] cause(s) the frequency of certain alleles in a population to vary over time. 13. [Isolation / Extinction] is the condition in which two populations of the same species cannot breed with one another. 14. Generally, when the individuals of two related populations can no longer breed with one another, the two populations are considered to be different [organisms / species]. Section 13-2: Evidence of Evolution Fossils Provide an Objective Record of Evolution Mark each statement below T if it is true or F if it is false. 1. Modern whales evolved from four-legged land animals. 2. Fossil links between the major classes of vertebrates have been found. 3. The age of Earth cannot be determined. 4. Scientists have discovered fossils for all species that have ever lived. 5. Paleontologists use radiometric dating to arrange fossils in sequence from oldest to youngest. 6. Fossils form when organisms are rapidly buried in fine sediment. Biological Molecules Contain a Record of Evolution 7. Species that diverged recently have genetic differences than those species that are not closely related. 8. There is (are) difference(s) between the amino acid sequences of the hemoglobin in humans and the hemoglobin in gorillas. 9. There is (are) difference(s) between the amino acid sequences of the hemoglobin in humans and the hemoglobin in frogs. 10. There is (are) difference(s) between the amino acid sequences of the hemoglobin in humans and the hemoglobin in rhesus monkeys. 11. Scientists are able to determine the exact nucleotide sequence of a(n). 50 Biology: Principles and Explorations Directed Reading Chapter 13
Read each question, and write your answer 12. How do scientists estimate the number of nucleotide changes that have taken place in a gene since two species diverged from a common ancestor? 13. Why do phylogenetic trees provide strong evidence of evolution? Anatomy and Development Suggest Common Ancestry In the space provided, write the letter of the description that best matches the term or phrase. 14. vestigial structures 15. homologous structures 16. vertebrate embryos 17. gradualism 18. punctuated equilibrium Section 13-3: Examples of Evolution Natural Selection Changes the Makeup of Populations 1. The presents many different challenges to an individual s ability to reproduce. 2. Organisms tend to produce more than their environment can support. 3. The traits of the individuals best suited to a particular environment tend to in a population over time. a. the model of evolution in which gradual change over a long period of time leads to species formation b. structures that have no use or little use and are evidence of an organism s evolutionary past c. the model of evolution in which periods of rapid change in species are separated by long periods of little or no change d. structures that share a common ancestry e. pharyngeal pouches and tails are evidence of evolution 4. Individuals of a species often with one another to survive. 5. Individuals within a population that are better able to cope with the challenges of their environment tend to leave the environment. offspring than those less suited to Biology: Principles and Explorations Directed Reading Chapter 13 51
Read each question, and write your answer 6. What is industrial melanism? 7. Describe the study conducted by Peter and Rosemary Grant. 8. What was the environmental challenge in Grant s study? 9. What was the effect of natural selection on beak size in Grant s study? The Formation of New Species Begins with Small Changes In the space provided, explain how the terms in each pair differ in meaning. 10. divergence, speciation 11. ecological races, species 12. In frogs, different mating seasons are a(n) to reproduction. 13. Reproductive is the inability of formerly interbreeding groups to mate or produce fertile offspring. 14. The way that natural selection leads to the formation of new has been thoroughly documented. 52 Biology: Principles and Explorations Directed Reading Chapter 13
9. minerals 10. mycorrhizae 11. Mutualism 12. because animals need plants for food 13. Arthropods have a hard outer skeleton and jointed limbs. 14. lungs 15. amphibians 16. reptiles 17. continental drift 18. 2 19. 4 20. 1 21. 3 CHAPTER 13 The Theory of Evolution SECTION 13-1 1. T 2. T 3. T 4. T 5. T 6. Lamarck proposed that during an individual s lifetime, structures increase or decrease in size according to their use. These acquired traits are then passed on to the offspring. 7. Darwin had a reasonable explanation for changes in the Earth s surface. Also, he found similarities between organisms over space and time. 8. A species is a group of genetically similar organisms that can interbreed and produce fertile offspring. A population is a group of organisms of the same species living in a given place at the same time. A population is a subset of a species. 9. Adaptation is the changing of a species to become better suited to its environment. Natural selection is the process by which populations change in response to their environment. 10. more 11. Genes 12. Natural selection 13. Isolation 14. species SECTION 13-2 1. T 2. T 3. F 4. F 5. T 6. T 7. fewer 8. one 9. 67 10. eight 11. gene 12. Scientists compare the nucleotide sequence of genes. 13. Phylogenetic trees show the same relationship indicated by the fossil record. 14. b 15. d 16. e 17. a 18. c SECTION 13-3 1. environment 2. offspring 3. increase 4. compete 5. more 6. the darkening of populations of organisms over time in response to industrial pollution 7. The Grants measured the beaks of many Galápagos finches year after year. 8. The environmental challenge was the decrease in the number of small, tender seeds during dry years. This decrease required the birds to eat larger, tougher seeds. 9. Natural selection increased the average beak size during dry years and decreased the beak size during wet years. 10. The accumulation of differences between groups is called divergence. Speciation is the process by which new species form. 11. Ecological races are populations of the same species that differ genetically because of adaptations to different living conditions. When ecological races become so different that they cannot interbreed, they are considered separate species. 12. barrier 13. isolation 14. species CHAPTER 14 Human Evolution SECTION 14-1 1. primates 2. dinosaurs 3. grasping 4. front 5. distances 6. prosimians 7. 38 8. lemurs 9. anthropoids Biology: Principles and Explorations Directed Reading Answer Key 191