History of Evolutionary thought - Human Evolution - Exam | ANTH 1001, Exams of Human Genetics

Download History of Evolutionary thought - Human Evolution - Exam | ANTH 1001 and more Exams Human Genetics in PDF only on Docsity! 1/21/2015 1 History of Evolutionary Thought January 21, 2015 Today’s objectives • Description of the course structure • Introduction to anthropology, science, and evolution • Evolutionary theory • Darwin…maybe 2 First off, the syllabus… Know it! 3 Course structure Learn about the present first, in order to understand the past. 4 3 sources of information • Readings: introductory background and details in narrative form • Labs: details and hands-on experience • Lecture: the big picture and new material, including documentaries 5 Textbook • Standord, CS, Allen JS, & Antón, SC (2013). Biological Anthropology, 3e. Prentice Hall/Pearson. 6 1/21/2015 2 Lab manual Anthropology 1001 Human Evolution Lab Manual for Spring 2015 7 Moodle Course Site • .pdf files of lecture slides for you to view or print out. The slides on a given topic will be posted after the lecture • Syllabus, assignments, exam keys, etc. available to view or print 8 Slide numbers to help in lecture 9 Grade assessment: Lecture • 1 midterm (20%) and 1 final (25%) • Objective questions (multiple choice, T/F, matching, etc) • No makeups 10 Grade assessment: Lecture • Active Learning Assignments (ALAs), given in lecture (10%) • 10 best scores will be compiled for this grade • Variety of in-class activities that are assigned and collected during lecture • No makeups allowed. There are guaranteed to be more than 10 ALAs 11 Grade assessment: Lab • Lab participation and pre-lab assignments • Must attend your assigned lab section each week (see syllabus and TA for makeup policy) • You cannot pass the class if you do not attend lab • There is NO lab this week!! 12 1/21/2015 5 adaptation allele Australopith biface cladistics Dmanisi fitness genotype haplorhine hominin homology ilium Jean Lamarck lemur mutation Olduvai Gorge pleiotropy polymorphism prognathic pronograde Raymond Dart sagittal crest stratigraphy taxon 25 Hard class ≠ Hard class to pass 26 Questions? 27 ALA #1: Introductions • Step 1: Take out a piece of paper • Step 2: Write the following down • Name • Major (if unknown, what are you interested in) • How can understanding human evolution relate to your major interests? • Something you already know about the subject of human evolution • Anything else you think Reed and I should know about you • Step 3: Hold on to you paper (turn it in at the end) • Step 4: Get to know the people around you 28 What is anthropology? 29 The four sub-fields of anthropology 30 1/21/2015 6 What is biological anthropology? 31 Biological anthropology • The study of humans as a biological organism • Our evolutionary history • Paleoanthropolgy • Primatology • Evolutionary theory • How our evolutionary history and biology interact with our culture, and how culture is affected by our biology • Evolutionary psychology • Human life-history • Modern human diversity • Medicine, biomechanics, and medical anthropology 32 Why is this (sub)field important? 33 The importance of biological anthropology • Biological anthropology helps inform effective economic and social policies, helps create effective medicine, helps avoid racist eugenics type movements, helps conservation efforts of primates. • What does it mean to be human? • How are humans different from other animals? Mammals? Primates? • How are we the same? • Nature vs. nurture? • Will humans survive climate change? What about other organisms? 34 How do we do this? 35 The scientific method • A systematic and consistent way to conduct scientific investigations • Hypothesis • Predictions • Test through measurement and observations • Revise hypothesis • Go to step two 36 1/21/2015 7 Scientific reasoning You must be willing to disprove your hypothesis with data collected in the observable world 37 Features of science • Testable hypothesis • Ideas can be falsified with data collected in the real world • Theoretically consistent across disciplines • E.g., physics, chemistry, biochemistry, biology, psychology • Social process carried out by fallible, biased individuals • Scientists don’t have all the answers • Not as a group or as individuals • Ongoing process • Self-improving and self-correcting process • In the long-run, good ideas win 38 Peer review process 39 40 Data and the ladder of abstraction Criticism of interpretation Interpretation of popularizations Popularization of results and criticisms Criticism of results Contextualization of results Interpretation of results Analysis Data Where does the public typically access knowledge? 41 Data and the ladder of abstraction Criticism of interpretation Interpretation of popularizations Popularization of results and criticisms Criticism of results Contextualization of results Interpretation of results Analysis Data Where does the public typically access knowledge? 42 Mostly Rarely University Courses? Grad and post-grad research 1/21/2015 10 Lord William Thompson Kelvin (1824-1907) • Defined the lower limit of the thermodynamic temperature scale (absolute zero) • Cooling body experiments • Earth is 20-40 million years old 55 Mary Anning (1799-1847) • She sells seashells??? • Fossil hunter with her father • Sold fossils on at the beach • Discovered Ichthyosaurus and Plesiosaurus 56 Georges Cuvier (1769-1832) • Needed to address the increasing number of fossil organisms that exist nowhere on Earth today • Extinction • “Catastrophism” – regional disasters 57 James Hutton (1726-1797) • Established the principle of “uniformitarianism” • “The present is the key to the past.” • The theory that the Earth’s features are the result of long- term processes that continue today as they did in the past. • Believed Earth was infinitely old • “…find no vestige of a beginning, no prospect of an end.” (1788) 58 Charles Lyell (1797-1875) • Uniformitarianism proponent • Contributed to solving the problem of a “young Earth” • Argued that geological features results from tiny changes accumulating over vast expanses of time 59 The changing tide Taxonomy 60 1/21/2015 11 John Ray (1627-1705) • Minister educated at Cambridge • Recognized that animals and plants could be placed into groups based on their ability to mate with one another (species) • Species are groups that are reproductively isolated • Also, recognized that species frequently share characteristics with others 61 Carolus Linnaeus (1707-1778) • Systema Naturae: a nested hierarchical classification of life • Unified classification system • Binomial nomenclature • E.g. Homo sapiens • Firm believer in fixity of species! • Shared physical traits • First to group humans with apes • Humans are animals! 62 It is not pleasing to me that I must place humans among the primates, but man is intimately familiar with himself. Let’s not quibble over words. It will be the same to me whatever name is applied. But I desperately seek from you and from the whole world a general difference between men and simians from the principles of Natural History. I certainly know of none. If only someone might tell me one! -Linnaeus 1747 63 The changing tide Economics 64 Adam Smith (1723-1790) • “Father of modern economics” • Individuals pursuing self-interest create wealthier communities 65 Thomas Malthus (1766-1834) • Populations have the capacity to increase exponentially • This leads to war, famine, and disease • Natural populations are kept in check by forces with kill off members of that population 66 1/21/2015 12 The changing tide Evolutionary Theory 67 Jean Baptiste (Pierre Antonie de Monet, Chevalier de) Lamarck (1744-1829) • First comprehensive scientific hypothesis of evolution • Mechanism: Acquired characteristics (Philosophie Zoologique) – use/disuse 68 Jean Baptiste (Pierre Antonie de Monet, Chevalier de) Lamarck (1744-1829) • First law: • Change in environment causes changes in behavior (NEW IDEA!) • Leads to greater or lesser use of given structures or organs • Second law: changes developed within the lifetime of an individual are heritable • Challenged the belief that species were immutable 69 Acquired characteristics: use and disuse So close, but so far away… • An organism passes on to its offspring features that are developed throughout its lifetime • Change in environment causes change in behavior of organism • This leads to greater and lesser use of particular structures and features • Use causes a thing to develop; disuse causes a thing to atrophy • All changes are heritable 70 So questions are beginning to accumulate… • Its pretty clear that Earth is older than once thought, but is it old enough? • There are serious questions about the supposed immutability of species: • How do species originate? • Why are some species so similar? • For very different species, why do they still share some similar characteristics? • Do species change? • Why do some species go extinct? 71 Questions? 72 1/21/2015 15 2. All organisms share a common ancestry • All organisms (on Earth) are related by descent from a common ancestor 85 Darwin’s first tree of life sketch – 1837 86 3. Evolution is gradual • Small changes over time • “Grades” or steps • Not slow, but step by step and persistent • If Earth is millions of years old, then there is plenty of time 87 If Earth’s history fit into one year… 88 January 1: Earth forms March 7: Oldest surviving rock on Earth from here November 10: Oldest shelled fossils November 22: First fish November 28: First land plants and animals December 13: Dinosaurs appear December 14: First mammals December 26, evening: Dinosaurs go extinct December 31, 11:35pm: Hominins appear 4. Evolution leads to speciation • Evolution leads to new species • Eventually, accumulating changes interfere with reproduction among new, descent populations 89 5. Evolution occurs through Natural Selection • The primary (active/non-random) mechanism for evolution is natural selection 90 1/21/2015 16 Natural selection • More individuals are born than survive to reproductive age • Some individuals are better at surviving and reproducing others • These individuals will leave more descendants – who will inherit these advantageous traits • Populations will therefore change over time • Differential reproductive success based on variations in heritable traits • Natural selection operates on individuals, either favorably or unfavorably, but it is the population that evolves! 91 3 necessary and sufficient conditions for natural selection • Variation in a trait • Inheritance of that trait • Differential reproductive success*** 92 ***Heads-up Textbook Change*** • SAA, page 30, Three Necessary and Sufficient Conditions of Natural Selection • Variation in a trait • Inheritance of that trait • Differential reproductive success based on that trait*** 93 Natural selection in action Peppered Moth (Biston betularia) • Before the Industrial Revolution: very few dark moths • By 1895: 98% of moths in Manchester were dark 94 95 Frequency of dark peppered moths 961956 1996 1/21/2015 17 Results of long-term selection • NS shapes adaptations • The result of long-term selection in one direction • Adaptation: a trait that increases the reproductive success (fitness) of an organism 97 98 Perfect Adaptation Adaptations always have a cost and so there is an inherent trade-off The peacock problem • Darwin: “The sight of the peacock’s tail makes me sick.” • His solution: sexual selection 99 Sexual Selection • Traits selected that are involved in mating • Male-male competition and female choice result in sexual dimorphism 100 Darwin’s 5 theories regarding the transmutation of species 1. Species change 2. All organisms share a common ancestry 3. Evolution is gradual (not slow, gradual!) 4. Evolution leads to speciation 5. Evolution occurs through natural selection This is not A THEORY of evolution but 5 THEORIES! 101 Questions? 102 1/21/2015 20 Common Misconception #3 Human evolution is over “Our species has reached its biological pinnacle, and is no longer capable of changing.” -Professor Steve Jones, University College of London 115 Actually, evolution is continuing and human evolution may be getting faster… 116 Common Misconception #4: The Naturalistic Fallacy The idea that what is natural is morally justifiable 117 Nature and Morality What are some things that are: 1. Natural and good? 2. Natural and bad? 3. Unnatural and good? 4. Unnatural and bad? 118 Nature ≠ Morality Natural Unnatural Good Babies Knowledge Love Books Modern medicine Craft specialization Bad Epidemics Famine Extinctions Parasitism Human slavery Pollution Nuclear weapons 119 Caterpillar Wasp 120 1/21/2015 21 Our intelligence and reasoning is also the result of Darwin’s “radical idea” We have the choice to apply whatever system of morality we want (just because something IS doesn’t mean that’s the way it OUGHT to be) 121 Questions? 122 Take-home messages • Darwin’s “theory of evolution” is really five theories: 1. Species change over time 2. Evolution is gradual 3. The primary mechanism is natural selection 4. Evolution causes speciation 5. All organisms (on Earth) are related by descent from a common ancestor 123