Chapter Content Mastery Natural Selection LESSON 1 Directions: Circle the term in parentheses that correctly completes the sentence. 1. Darwin hypothesized that species in the wild evolve through a process called (natural selection/selective breeding). 2. Darwin observed that tortoises living on islands within 50 miles of one another were (different from/similar to) each other. 3. Darwin was fascinated by the diversity of (beak/wing) size and shape in Galápagos finches. 4. The variation between a cocker spaniel and a Great Dane is the result of (natural selection/selective breeding). 5. Beneficial traits that are (developed by/inherited by) parents can be passed on to offspring. 6. One of the reasons species evolve is that animals often produce (more/fewer) offspring than an environment can support. 7. Geographic isolation (does/does not) contribute to evolution. 8. Traits that increase an organism s chance of survival are called (adaptations/generations). Directions: Summarize each of the four requirements below that explain Darwin s theory of evolution by natural selection. 9. overproduction 10. variation 11. inherited variation 12. natural selection The Process of Evolution 11
Chapter Content Mastery Adaptation and Extinction LESSON 2 Directions: Match the examples of adaptations below with the type of adaptation it represents from the following list. A. behavioral B. camouflage C. mimicry 1. The Clapper Rail builds its nest in tall, grassy marsh plants. 2. The lava lizard has blackish-colored skin. 3. Young Sally Lightfoot crabs are dull grey like volcanic rocks on the Galápagos Islands. 4. The Snake Eel looks like the Banded Sea Snake. 5. The frogfish has a body part that looks like another animal s food source. 6. The Satin Bower bird uses berries, saliva, and blue scraps to decorate its nest and attract a female. Directions: Describe how each of the following contributes to the extinction of a species. 7. loss of habitat 8. loss of genetic diversity 9. competition with exotic species 10. inability to adapt Directions: Respond to the following statement in the space provided. 11. Explain how species of organisms adapt over time to their environments. 12 The Process of Evolution
Reinforcement Natural Selection LESSON 1 Directions: Write the letter of the corresponding term on the line next to its definition. 1. the process of intentionally breeding a plant or animal for specific characteristics 2. an inherited trait that increases an organism s chance of surviving and reproducing in a particular environment 3. a person who studies the natural world, including plants, rock formations, and animals 4. a group of organisms that represent one step in a line from an ancestor 5. the number of organisms of one species that occupy an area A. adaptation B. evolution C. genetic variation D. naturalist E. natural selection F. population G. selective breeding H. generation 6. genetic change in a population over time 7. the process by which individuals with traits better suited to an environment are more likely to survive and pass on those traits to future generations 8. the diversity of traits that are passed on to a generation of organisms Directions: Answer each question below in the space provided. 9. What did Darwin discover about finches on the Galápagos Islands, and how were these discoveries important to his theory of natural selection? 10. Why do you think Darwin considered the phrase the struggle to survive an appropriate description of natural selection? The Process of Evolution 15
Reinforcement Adaptation and Extinction LESSON 2 Directions: Respond to each question or statement in the space provided. 1. Is it possible for a negative trait (one that does not contribute to species survival) to stay in a population for a period of time? Explain. 2. Give an example from your own environment of one species with a structural adaptation and one species with a behavioral adaptation. Describe how each example contributes to the species survival. A. structural adaptation B. behavioral adaptation 3. Give at least two examples where humans have observed species adaptations, such as camouflage and mimicry, and copied them for their own purposes. 4. What does it mean for a species to be threatened? Directions: Name three causes of extinction, and discuss the role of humans in each. 5. Cause: Human Role: 6. Cause: Human Role: 7. Cause: Human Role: 16 The Process of Evolution
Content Vocabulary Directions: Fill in each blank in the following sentences with the correct term from the list below. adaptation camouflage evolution extinct generation mimicry naturalist natural selection population selective breeding 1. is a process by which individuals with traits better suited to an environment are more likely to survive and reproduce than individuals without those traits. 2. One organism resembling another in appearance or behavior is known as. 3. Charles Darwin was a, or a person who studies the natural world. 4. The passenger pigeon and the dodo are among many animal species that have become. The Process of Evolution 5. People often practice in order to produce plants or animals with desirable traits. 6. Animals that blend in with their surroundings are using. 7. Inherited traits are passed from one to another. 8. Darwin s theory describes how natural selection can lead to the of new species. 9. A refers to the number of organisms of one species that live in an area. 10. An inherited trait that increases an organism s chance of surviving and reproducing in a particular environment is an. Directions: Decide whether each of the adaptations described below is behavioral (B) or structural (S). Then write a B or an S in the blank. 11. a jack rabbit s long back legs 12. a jaguar s patterned coat 13. a bear hibernating 14. the singing of a tree frog 15. a wood duck building a nest in a tree hole 16. a spider spinning a web The Process of Evolution 19
Content Vocabulary CONTINUED Directions: Use each of the following terms in a sentence that demonstrates its meaning. 17. threatened 18. extinct 19. genetic variation 20. competition 21. misinterpret 22. habitat 20 The Process of Evolution
Chapter Review Part A. Vocabulary Review The Process of Evolution Directions: Unscramble the letters to form the correct word for each definition. 1. tenivuloo change in inherited traits over time 2. noitaviar a difference in an inherited trait that may eventually lead to a new species 3. centxti the elimination of all individuals in a species 4. padnotiata inherited trait that increases a species chance of surviving and reproducing in a particular environment 5. crimyim when one species looks or behaves like another 6. railastunt someone who studies the natural world 7. flumegacao blending in with the surrounding environment 8. louptionap the number of organisms of one species that occupies an area 9. otenergain a group of organisms that represent one step in a line from an ancestor 10. deathrente when the numbers of a species decline so much that there is little genetic variation Directions: Compare and contrast each of the following pairs of terms. 11. natural selection, selective breeding 12. behavioral adaptation, structural adaptation The Process of Evolution 21
Chapter Review CONTINUED Part B. Content Review Directions: Order the four steps of Darwin s process of natural selection below and then describe the importance of each step. inherited variation natural selection overproduction variation 1. 2. 3. 4. Directions: Respond to each statement using complete sentences. 5. Infer how Darwin s observation of Galápagos tortoises and finches helped him develop the theory of evolution by natural selection. 6. Speculate about how people might misinterpret the term adaptation. 7. Present one example of behavioral adaptation and one example of structural adaptation in organisms native to your area. 8. Develop a plan to reduce the extinction of species, using what you have learned about the causes of extinction. 22 The Process of Evolution
Chapter Outline The Process of Evolution Lesson 1: Natural Selection A. Charles was the first to compile persuasive evidence supporting evolution. 1. is genetic change in a population over time. 2. Darwin s transformed the natural sciences and serves as the basis of all biological research today. 3. Darwin served as a on the British naval ship the H.M S. Beagle. a. The sailed for five years from England to South America to make naval maps. b. Darwin observed, collected samples of new plants and animals, and wrote about places and organisms few people had seen. 4. Darwin s most unique findings were the diversity and uniqueness of organisms on the Islands, 1,000 km off the coast of South America. a. After comparing animals and animal fossils from different, he observed that they were different from organisms on the mainland. b. Darwin reasoned that some species might have originated in South America but had to be different. c. Darwin found enormous on all of the Galápagos Islands. d. Tortoises had shells and short necks where they ate lowgrowing plants. e. They had saddle-shaped shells and necks where they ate highgrowing cactus. f. Darwin concluded that the different tortoises descended from a common ancestral environment. in South America, but each evolved to fit its unique g. Darwin observed that finches on different islands had distinct sizes and shapes. 32 The Process of Evolution
Chapter Outline CONTINUED h. He concluded that the, like the tortoises, had a common South American ancestor, but that they became different to suit the different island. i. occurs when people breed plants and animals, such as vegetables or cows, to produce desired traits. j. Selective breeding does not produce new ; all dogs can still have offspring with their common ancestor, the wolf. B. Darwin s theory of states that organisms with traits that allow them to survive in particular environments pass traits on that could lead to new species. 1. is the creation of a diversity of traits through gamete formation. a. A harmful may cause an organism to die; a beneficial trait will be passed on to the next. b. Genetic variation is necessary for by natural selection to occur. 2. Animals often produce offspring than available resources can support. a. Thomas Malthus described this struggle to survive among the human. b. Darwin applied Malthus ideas to the for survival among individuals in a species. c. Organisms best prepared for living in specific habitats will survive and, and their will be best able to survive and reproduce as well. 3. New can develop if organisms with common ancestors become different environments. and natural selection causes them to differentiate in response to a. Inherited traits that increase an organism s chance of surviving and reproducing in a particular environment are called. b. Darwin s theory of evolution by natural selection includes four steps:, variation, inherited variation, and natural selection. The Process of Evolution 33
Chapter Outline CONTINUED c. Populations evolve as favorable in particular environments spread through generations. 4. After 20 years, Darwin published The of Species by Natural Selection. a. Darwin developed the idea that all organisms have descended with from common ancestors. b. Darwin believed that evolution by natural selection explains the Lesson 2: Adaptation and Extinction of modern organisms. A. Organisms evolve for specific environments through natural selection. 1. Adaptations are the result of a long process by which are passed from one generation to another. a. People may the word adaptation, believing adaptations occur within a generation and/or are rather than naturally selected. b. Not all inherited traits are adaptations; traits may stay in a population if they are to beneficial ones. c. Positive traits may help an organism to ; negative traits may cause it to die off. B. Two of adaptations are structural adaptations and behavioral adaptations. 1. are aspects of the physical body that help organisms survive and reproduce. a., or blending in with one s surroundings, is a type of structural adaptation. b. Lizards change to blend in with their surroundings; animals sometimes have camouflage coloration when they are more vulnerable to predators. 34 The Process of Evolution
Chapter Outline CONTINUED c. is when one species looks or behaves like another. d. Some organisms look like other dangerous or poisonous organisms to discourage predators. e. In another type of mimicry, a species fools its by looking inviting or familiar. 2., also called instincts, depend on the actions of an organism. a. Clapper rails build their so that they will rise and fall with wetland tides. b. The male satin bower bird its nest to attract a female mate. C. A species becomes when all of the individuals of that species are wiped out. 1. Several major events in the of Earth have led to extinctions. 2. Major of extinction are habitat destruction, loss of genetic diversity, and introduction of exotic species. a. Habitats for plants and animals as humans develop and occupy more space. b. The fewer the individuals left of a species, the less in the population. c. A species is if there are so few individuals that the lack of genetic diversity could lead to species extinction. d. The introduction of species can lead to competition with native species. e. If the exotic species has few, it can out-compete native species and push them toward extinction. 3. If environmental change occurs where only small populations of a species exist, lack of could lead to extinction relatively quickly. The Process of Evolution 35