Biology Partnership (A Teacher Quality Grant) Evolution Nancy Dow Jill Hansen Tammy Stundon April 12, 2014 Gulf Coast State College Panhandle Area Educational Consortium 5230 West Highway 98 753 West Boulevard Panama City, Florida 32401 Chipley, Florida 32428 850-769-1551 877-873-7232 www.gulfcoast.edu Florida Next Generation Sunshine State Standards • SC.912.L.15.1 Explain how the theory of evolution is supported by fossil record, comparative anatomy, comparative embryology, biogeography, molecular biology, and observed evolutionary change. • SC.912.L.15.10 Identify basic trends in hominid evolution from early ancestors six million years ago to modern humans, including brain size, jaw size, language, and manufacture of tools. • SC.912.N.3.1 Explain that a scientific theory is the culmination of many scientific investigations drawing together all the current evidence concerning a substantial range of phenomena; thus, a scientific theory represents the most powerful explanation scientists have to offer. Clarifications • Students will identify evidence and/or explain how the scientific theory of evolution is supported by the fossil record, comparative anatomy, comparative embryology, biogeography, molecular biology, and observable evolutionary change. • Students will identify examples of and basic trends in hominid evolution from early ancestors to modern humans. • Students will explain the development of a theory. • Students will recognize the differences between theories and laws. Content Limits • Items assessing evolution will focus on a conceptual understanding of the supporting scientific evidence. • Items will not require memorization of the names of specific human fossils or the names of the different hominid species. • Items assessing the fossil record must focus on the fossil rather than geologic formations in isolation. • Items assessing the fossil record will not require understanding of the specific mechanisms used for relative dating and radioactive dating. • Items will not require the memorization of the geologic time scale, including era, period, and/or epoch. • Items referring to adaptive radiation, convergent evolution, coevolution, or punctuated equilibrium should focus on the concepts rather than on the definition of the terms. • Items referring to the development of language or the manufacturing of tools will relate this development to changes in the skull or brain size. • Items will not assess types of genetic mutation or how these mutations occur. • Items referring to comparative anatomy and comparative embryology will assess anatomical similarities such as homologous structures and vestigial organs but will not require specific knowledge of embryologic stages or structures • Items may assess how the overall contributions of scientists such as Darwin, Lamarck, Lyell, Malthus, Mendel, or Wallace aided in the development of the scientific theory of evolution. • Items will not assess the differences among intelligent design, creationism, and the scientific theory of evolution. • Items assessing a scientific claim, the development of a theory, or the differences between theories and laws are limited to the scientific theory of evolution. • SC.912.L.15.13 Describe the conditions required for natural selection, including: overproduction of offspring, inherited variation, and the struggle to survive, which result in differential reproductive success. (MODERATE) • SC.912.L.15.14 Discuss mechanisms of evolutionary change other than natural selection such as genetic drift and gene flow. (MODERATE) • SC.912.L.15.15 Describe how mutation and genetic recombination increase genetic variation. (Moderate) Benchmark Clarifications – Students will explain and/or describe the conditions required for natural selection that result in differential reproductive success. – Students will explain and/or describe the scientific mechanisms, such as genetic drift, gene flow, and nonrandom mating, resulting in evolutionary change. – Students will explain and/or describe how mutation and genetic recombination increase genetic variation. – Students will identify ways in which a scientific claim is evaluated (e.g., through scientific argumentation, critical and logical thinking, and consideration of alternative explanations). Content Limits – Items will not address descent with modification or common descent. – Items addressing mutation and genetic recombination in relation to increasing genetic variation must be assessed in the context of evolution. – Items will not assess the Hardy-Weinberg principle or genetic equilibrium. – Items may address how meiosis contributes to genetic variation but may not assess the steps or stages of meiosis. – Items assessing a scientific claim are limited to the topics discussed in SC.912.L.15.13, SC.912.L.15.14, and SC.912.L.15.15. Teaching Evolution • • • • • Responsibility Communicate your passion Tell good stories Engage the students Teach a complex topic like evolution that is easy for 12 year olds to understand, but not too simple. Evolution surfaces throughout a biology curriculum; refer to it. “Nothing in biology makes sense except in the light of evolution.” – Dobzhansky Richard Dawkins talks with a high school student. Teaching evolution • Key points: – – – – Evolution: Decent with modification Earth History – Use the 24 hour clock analogy Charles Darwin – start with the story! Variation/mutation, inheritance, and selection – finches to bacteria…. – Speciation – best shown as the branching ‘tree of life” model – Evidence of evolution – from radiometric dating to embryological evidence – Human evolution – Story of “Lucy”, human thumb activity, skull activity… Lee Meadow’s “The Missing Link” • An inquiry approach for teaching all students about evolution. • Don’t say evolution is ‘just a theory’ • Many students feel they have to defend their faith. Relieve that feeling. • http://leemeadows.blogspot.com/ Evolution X Evolution is NOT linear, so where did this come from? Evolution Intelligent Design is NOT in the standards. Do not approach the topic OR even state “versus.” This is truly NOT a topic, or the place, where students need to feel they need to defend their faith. Survival of the Sneakiest Survival of the Sneakiest Discussion questions • When it comes to crickets, what does fitness mean? • Is calling good or bad for a cricket's fitness? • Give some examples of selection at work in this cricket story. • How does selection favor calling? How does selection favor not calling? ? How long can a fruit fly survive without food? “SURVIVAL OF THE FITTEST”—ONLY THE ‘BEST’ FLY WILL SURVIVE AND BE ABLE TO REPRODUCE AND PASS IT’S GENES ON TO THE NEXT GENERATION.IT IS THEN SAID TO BE ‘FIT’-THIS IS NATURAL SELECTION. Number of flies AVERAGE STARVATION RESISTANCE The average fruit fly can survive about 20 hours without food. A MORE GENETICALLY ‘FIT’ FLY GENETICALLY ‘UNFIT’” FLY Hours until starvation THE EXPERIMENT = 500 fruit flies Food removed Food returned Only the most starvationresistant flies live to lay eggs. ? 1 INITIAL SETUP Start with a cage that contains a large number of fruit flies (5,000), and remove the food. 2 TESTING STARVATION RESISTANCE Wait until 80% of the starve to death, Eggs flies then return the food to the cage. Record the New generation average starvationresistance time. Can fruit flies evolve so that they can resist starvation longer? Can we see Natural Selection at work? (YES) 3 START NEW GENERATION After the surviving flies eat a bit, collect the eggs those flies lay and transfer them to a new cage. GENERATION 1 Average starvation resistance: 20 HR. Hours until starvation GENERATION 2 Average starvation resistance: 23 HR. Hours until starvation Experiment continues through 60 generations. GENERATION 60 Average starvation resistance: 160 HR.---this is evolution (change) at work Number of flies Number of flies Number of flies THE RESULTS Hours until starvation Over many generations of natural selection, the population changes! The flies now resist starvation much longer. THE EVOLUTIONS OF POPULATIONS THERE ARE FOUR MECHANISMS THAT CAN GIVE RISE TO EVOLUTION: 1.MUTATION 2.GENETIC DRIFT 3.MIGRATION (Gene Flow) 4.NATURAL SELECTION Greatly and quickly seen in isolated populations like those on islands. -Allele frequency will change over generations; situations/EVR will favor one allele over another -Those populations at equilibrium are not evolving -Species with more genetic diversity will adapt better to environmental changes Mutations five • Rare because you have self correcting enzymes • Natural Process that produces genetic diversity • Not all mutations are bad – Some won’t affect the body at all digit s wrist bone Genetic Drift • Blood types/ear lobes – Some are advantageous (thumb) Random selection….need a constant change and variety of alleles to survive Migration (Gene Flow) Natural Selection Three conditions for NS to occur: 1. Variation of the trait 2. Trait must be inheritable 3. One version is in greater abundance Each mechanism changes the allele frequency • With your ipad/smart phone go to http://science.discovery.com/games-andinteractives/charles-darwin-game.htm • Or google “Darwin evolution game” • If you survive, let me know! 1. Why is it beneficial to have diversity in a population? 2. What were some of the selective pressures in your environment that accented the survival of some of you population? 3. What were you looking for in the mutation lifeline to help your population survive? 4. Based on your experience in playing this game, do you think there have been more extinctions of species than successes of various species? Explain. Evolution does not work this way Organisms with favorable genetic variations will tend to survive and breed successfully Comparative embryology: Similar embryo development in closely related species similar embryos, diverse organisms Investigating Hominoid Fossils. Homologous and Analogous Structures Homologous structures show evidence of a common ancestor Analogous structures have a similar function but not a common ancestor. Similar structures are due to a common environmental pressure/need. Human Thumb Activity With the thumb came the power and precision grips use of tools! An advantageous characteristic of most species in the genus Homo. The Most FIT!!!! Dog versus Wolf Card Game Evolution Thinket • Additional Resources: – Understanding Evolution website- Berkley – http://www.pbs.org/wgbh/evolution/edu cators/lessons/lesson5/act1.html – http://www.elucy.org/ – Evolution of Cetaceans • Next slide for more resources Or Die! The Natural History Museum presents “The evolution game” http://www.nhm.ac.uk/nature-online/evolution/what-isevolution/natural-selection-game/the-evolution-experience.html This game is all about natural selection, the player plays the role of a young bird which must survive in order to reproduce. You must eat enough bugs to survive each season, but the color of the bugs changes depending on which bugs are easiest to find. The Big Picture on Evolution http://www.wellcome.ac.uk/stellent/groups/corporatesite/@msh_publi shing_group/documents/we b_document/wtd026042.pdf This teaching resource from the Welcome Trust is a short issue all about evolution. It explains the research and applications of evolution as well as the history – great for older kids, or those interested in learning more. Follow up •Q & A •Post Test