Solution Manual for Exploring Biological Anthropology: The Essentials, 4th Edition

CHAPTER TWO ORIGINS OF EVOLUTIONARY THOUGHT LEARNING OBJECTIVES After reading and carefully considering Chapter Two, students should be able to: • • • • • 2.1: Explain how science differs from other ways of understanding the world. 2.2: Explain the contributions of earliest scholars before Darwin to the development of evolutionary theory. 2.3: Identify the contributions of the thinkers just before Darwin’s time and how they helped him formulate his ideas. 2.4: Summarize the ideas of Charles Darwin and how he developed them. 2.5: Explain the difference between science and faith-based explanations of life. LEARNING OBJECTIVES SUMMARY WHAT IS SCIENCE? 2.1 Explain how science differs from other ways of understanding the world. • Science is a progressive, self-correcting, evidence-based way of understanding the world. • Faith’s evidence is the Bible, and it is impervious to evidence and hypothesis testing. THE EARLY THINKERS 2.2 Explain the contributions of earliest scholars before Darwin to the development of evolutionary theory. • Carol von Linnaeus revolutionized the study of living things by classifying them according to similarities in form. THE ROAD TO THE DARWINIAN REVOLUTION 2.3 Identify the contributions of the thinkers just before Darwin’s time and how they helped him formulate his ideas. • Many pre-Darwinian thinkers accepted evolution and put forward theories for the mechanism. • Darwin was influenced by three eminent French natural historians: Comte de Buffon, Georges Cuvier, and Geoffroy Saint-Hilaire. • Lamarck proposed that the use of a trait could influence an offspring’s phenotype in the next generation. Darwin showed that change could occur across generations based only on the selective retention of some traits and the filtering out of others. THE DARWINIAN REVOLUTION 2.4 Summarize the ideas of Charles Darwin and how he developed them. • Charles Darwin spent his life thinking and writing about evolutionary change, and he developed the theory of evolution by natural selection to account for it. • Alfred Russel Wallace was a contemporary of Darwin and codiscoverer of the theory of evolution by natural selection. • Natural selection can occur only if a trait can be inherited, if there is variation within a population, and if there is pressure from the environment. SCIENCE AND CREATIONISM 2.5 Explain the difference between science and faith-based explanations for life. 5 Copyright © 2017, 2013, 2009 Pearson Education, Inc. All rights reserved. • Intelligent design creationism is a recent attempt to repackage old creationist ideas in a way that argues for a divine force without calling it God. LECTURE OUTLINE I. Introduction A. Battles between teaching evolution and creationism 1. The Dover Case & the Scopes Trial B. Life on Earth as unchanging 1. The scale of evolution 2. Uses of the term theory II. What is Science? A. The scientific method 1. Developing a hypothesis: a preliminary explanation of a phenomenon 2. Moving from observation to data to experiment 3. Experiments: the testing of a hypothesis, before the researcher can truly stake his or her claim B. Science is an empirical process 1. Theories are self-correcting a. Contradicting claims can be examined and resolved by examining data b. Earlier mistakes can always be corrected 2. Theories are falsifiable a. Science uses paradigms, conceptual frameworks for understanding a body of evidence b. Changing paradigms is a long, slow process III. The Early Thinkers A. The Roots of Modern Science 1. The concept of immutability of species a. For centuries, life was thought of as an orderly, hierarchical ladder 2. The church set the doctrine during the Middles Ages a. Fixity of species was the spiritual, legal, and political norm b. Aristotle’s hierarchical Great Chain of Being 3. Changes came about during the Renaissance a. Scholar’s rediscovered ancient Greek and Roman knowledge and their approach to science became more “modern” b. Advances in human anatomy changed the way scholars looked at the human body 4. The Church’s power a. Abiding belief in single creation: James Ussher’s biblical calculations of the age of the Earth B. Linnaeus and the Natural Scheme of Life 1. John Ray first used the terms genus and species 2. Carolus Linnaeus built on Ray’s writings to develop his taxonomy a. Sorting organisms into categories helped to establish their relationships b. Taxa based on organisms’ similarities c. Linnaean system of taxonomy uses binomial nomenclature, or a two-level genusspecies label IV. The Road to the Darwinian Revolution A. In the eighteenth and early nineteenth centuries, European natural historians focused on explaining the diversity of life B. Three prominent French philosophers 1. Comte de Buffon a. Accepted general notion of biological change b. Observed that animals in new climates often change in response to environments c. Claimed that New World animals were weaker and smaller than Old World counterparts 2. Georges Cuvier a. Steadfast opponent of theory of evolution 6 Copyright © 2017, 2013, 2009 Pearson Education, Inc. All rights reserved. b. V. Advocated catastrophism to explain presence of dinosaur bones and changing organisms c. Catastrophism: the theory that there have been multiple creations interspersed by great natural disasters i. Noah’s flood 3. Geoffroy Saint-Hilaire a. An anatomist and a strong advocate of evolutionary change b. Debated creationist Cuvier c. Supported Lamarck’s explanation for the mechanism of evolution C. Jean-Baptiste Lamarck 1. His 1809 theory of inheritance of acquired characteristics (Lamarckianism) a. That organisms make adjustments to their environment during their lifetime b. Relies on the concept of need and use c. Animals who swim frequently would theoretically have offspring who could swim well d. In his theory, adjusted traits would be passed down to offspring 2. His major breakthrough was the relationship between organism and environment a. Theory’s central error is that evolution would take place in lifetime of individual organism b. Had no knowledge of genes c. Natural antecedent to Darwin’s theory D. The Uniformitarians: Hutton and Lyell 1. James Hutton a. Father of modern geology b. Saw clear evidence of past worlds in rock formations c. Uniformitarianism: same gradual geological process we observe today was operating in the past 2. Charles Lyell a. Proponent of uniformitarianism b. Friendship with Darwin influenced evolutionary theory c. Earth’s history understood in context of its ancient changes The Darwinian Revolution A. Darwin’s early years 1. Born into life of affluence 2. Left medical studies at University of Edinburgh 3. Studied for the ministry at Cambridge University a. Deeply influenced by his professor, botanist John Henslow B. The Galapagos 1. Five year voyage as the “gentleman” amateur naturalist aboard the HMS Beagle (1831–1836) 2. Explored South America, Australia, and Africa 3. Significant observations in the Galapagos Islands a. Each island had own species of finch with different physical traits b. Darwin did not immediately formulate theory c. These thirteen species of finch studied by John Gould in London 4. Gould’s study gave Darwin first insight into: a. Biogeography: the distribution of animals and plants on Earth b. Adaptive radiation: the diversification of one founding species into multiple species and niches c. Darwin referred to these biological changes as natural selection: differential reproductive success over multiple generations C. Refining the Theory of Evolution by Natural Selection 1. Spent years in study at home in England 2. Drew parallels to local breeders’ artificial selection in breeding livestock a. Same essential process, the selection of genes, as in natural selection b. Key difference is that natural selection does not have conscious goals 3. Galvanized to publish after receiving Alfred Wallace’s manuscript 7 Copyright © 2017, 2013, 2009 Pearson Education, Inc. All rights reserved. a. Lower-class Wallace was a field biologist b. Had developed own theory of evolution by natural selection 4. Darwin’s publication, On the Origin of Species, enjoyed widespread success and sales 5. Observations and Deductions in On the Origin of Species a. Observation 1: Malthus’s concept that all organisms have the potential for explosive growth b. Observation 2: In nature, populations are roughly stable c. Deduction 1: There must be a struggle for existence i. Bullfrog’s offspring survival rate d. Observation 3: Nature is full of variation, every individual unique e. Deduction 2: Some variations must be favored, and some disfavored, in natural selection 6. Natural selection centers on reproductive success a. Social theorist Herbert Spencer’s phrase “survival of the fittest” misleading b. Darwinian fitness: reproductive success 7. In order for natural selection to be at work: a. Trait in question must be inherited b. Trait in question must show variation between individuals c. The environment must exert some pressure on organisms 8. Evolution occurs in populations, not individuals a. Natural selection acts on mutations in a population VI. Science and Creationism A. Basis of Creationism 1. Book of Genesis as an alternative to science 2. Argument that Earth is very young 3. Sedimentary evidence of extinct animals as the product of Noah’s flood B. Reliance on faith 1. Old Testament not testable evidence 2. Must be accepted without scientific method C. Political aspects of creationism 1. Legal battles to teach creationism in schools a. Louisiana’s unconstitutional disclaimer on evolution b. Atlanta’s “alternatives to evolution” D. Creation science 1. Arguments against evolution a. Emphasize gaps in the fossil record b. Denial of science rather than science itself c. Includes Intelligent Design: proposes that natural selection cannot account for the diversity and complexity of form and function in nature E. Mandated division between church and state in U.S. Constitution 1. Rights of religious faiths or lack of faith equally respected 2. Science classrooms intended to train scientific thinking LECTURE AND DISCUSSION TOPICS Each of these topics is intended to generate ideas either for lectures or for discussion in the classroom. For most topics, students should be able to respond and participate in discussions based solely on reading the text. For others, students may need further reading or other forms of information to develop some personal perspective and become equipped to make independent decisions about the topics. 1. Lecture on evolution—Consider a lecture using some of the fossil evidence that Darwin had available when he was forming his theory. Discuss how fossils can show change through time. This would also be a way of introducing recent finds such as Homo naledi fossils from South Africa. 8 Copyright © 2017, 2013, 2009 Pearson Education, Inc. All rights reserved. 2. Perhaps incorporate a discussion of some of the recent findings about cloning and what this contributes to our understanding of evolutionary processes. Students will likely be interested in the ethical issues involved in manipulating evolutionary processes. 3. Consider also a discussion of the scientific method in this chapter, including its procedures and limitations. It can only deal with questions that are potentially or actually repeatable. Its steps are: (1) observation; (2) question or problem; (3) hypothesis/null hypothesis; (4) data collection/experimentation; and (5) formation of a conclusion. Stress the equal importance of honest, effective methodology and conclusion formation. Also explain that the scientific method is a continuous process, and these five steps repeat with major/minor modifications to the hypothesis. Describe the process of theory formation, a hypothesis supported by a large body of observations confirmed by many independent investigators. 4. As part of this lecture, describe how good theory formation (1) explains or shows relationships among facts; (2) simplifies; (3) clarifies; (4) grows to relate additional facts, which means it is always tentative in scope; (5) predicts new facts and relationships; and (6) does not explain too much. Theory becomes a scientific law if it possesses a high degree of certainty and is widely accepted within the scientific community. Stress to students that a scientific “fact” is an accurate description of an object or event based on what we know and what we know how to do. It is not an absolute finality. 5. Perhaps take the opportunity to discuss patterns of deductive and inductive logic. Talk about proof and rigor of proof in science. Be sure to emphasize that when we extrapolate from a scientific theory, it is only supposition, not scientific fact. 6. A lecture about the history of biology as a field of study might be useful, especially as it relates to the path that Darwin took to introduce his idea to the larger community of scientists. One way to examine this path is to look at the historical influences that helped shape biological theory immediately before Darwin and Wallace published their works. 7. Natural selection provides direction to evolutionary change, yet students often have trouble grasping the concept. Discuss examples of natural selection in detail and explore what “fitness” means in evolutionary terms. 8. Examine the influence of the Church on all science in Darwin’s time. Discuss examples of how the Church at that time regarded change in species and how that position has changed over time. CLASSROOM ACTIVITIES 1. Have students share their cosmologies and origin myths. Talk about similarities and differences in the ones expressed. As always with such discussions, it is necessary to establish a neutral atmosphere, with acceptance and patience for hearing others’ ideas. 2. Have your students read the 1858 paper titled, “On the Tendency of Varieties to Depart Indefinitely from the Original Type” by Alfred Wallace. Students should then compare Wallace’s conclusions to Darwin’s ideas about natural selection. Have them report their findings. 3. Discuss the students’ various religious and nonreligious beliefs about the origins of life. Emphasize again the importance for tolerance in listening to other students’ points of view. Further discuss the concept of Intelligent Design and how it is an intellectual, but not scientific, approach to explain evolutionary change. 4. Darwin used geology to help him make the case for descent with modification. Have students discuss how thoughts on the age of the Earth in Darwin’s time period kept many from believing that such changes to species could even occur. 9 Copyright © 2017, 2013, 2009 Pearson Education, Inc. All rights reserved. 5. Ask students to describe what kinds of species they see around them, at school or around their homes. Can they use any to talk about evolution? Have them list characteristics that might have been influenced by natural selection. RESEARCH AND WRITING TOPICS 1. Have students research an origin myth that is not their own using library sources and/or interviewing. Have them compare and contrast this myth with their own and explain how they reconcile competing claims of truth. This may be presented in written or oral form. 2. Have students complete written or oral biographical reports on one of the following men and how their scientific ideas contributed to Western thought: Georges Cuvier, Comte de Buffon, James Hutton, Charles Lyell, Charles Darwin, Jean-Baptiste Lamarck, or Alfred Russel Wallace. 3. Have students outline the steps Darwin used to describe how descent with modification worked. They should try to describe how he argued for the veracity of his findings and the evidence he used. 4. Have your students research scientific creation, evolutionism, theistic evolutionism, and creationism. In written or oral reports, or in a debate, have students defend a position they do not hold. Monitor, using a brief essay or opinion poll, how the students’ opinions may have changed based on what they have learned in the chapter. 5. Invite proponents of biological evolutionism, scientific creationism, and theistic evolutionism/creationism into your class. After each gives a short presentation of his or her views, they could engage in a debate in which students could participate. Discuss the Scopes trial and the controversy that marks the publication of biology textbooks in certain states. 6. Have students research the origins of Systema Natura, written by Linnaeus, and explain how it contributed to the development of modern biology. Students should understand how the nomenclature helps with information organization, which is critical to science. REVEL RESOURCES AND ACTIVITIES Activity: The Scientific Method Reading: Happy Birthday Linnaeus Activity: Lamarckian and Darwinian Views of Evolution Activity: Explore Darwin’s voyage on the HMS Beagle Reading: Testing Natural Selection 10 Copyright © 2017, 2013, 2009 Pearson Education, Inc. All rights reserved.