Exploring the Nature of Science in the Next Generation Science Standards: Understanding the Science of Nature through the Nature of Science (Part II) Dr. Paul Narguizian Professor of Biology and Science Education California State University, Los Angeles Email: pnargui@calstatela.edu Web Page: http://www.calstatela.edu/faculty/pnargui/ http://www.sci-news.com/paleontology/scienceanzu-wyliei-dinosaur-01811.html The “Chicken from Hell” http://www.sci-news.com/paleontology/scienceanzu-wyliei-dinosaur-01811.html U.S. paleontologists have discovered a new raptor dinosaur that lived in western North America during the Cretaceous period, about 66 million years ago. http://www.sci-news.com/paleontology/scienceanzu-wyliei-dinosaur-01811.html • What does the “Chicken from Hell” Anzu wyliei, the Nature of Science (NOS), and the Next Generation Science Standards (NGSS) have to do with one another??? Nature of Science Survey Answer “T” (True) or “F” (False) (Modified from the work of Steven M. Dickhaus) # Statement 1 Science can prove anything, solve any problem, or answer any question. 2 Different scientists may get different solutions to the same problem. 3 Science is primarily concerned with understanding how the natural world works. 4 Science can be done poorly. 5 Science is primarily a method for inventing new devices. 6 Scientists have solved most of the major mysteries of nature. 7 Science can study things and events that happened in the past, even if there was no one there to observe the event. 8 Most engineers and medical doctors are practicing scientists. 9 Scientists often try to disprove their own ideas. 10 Scientists can believe in God or a supernatural being and still do good science. 11 Any research based on logic and reasoning is scientific. 12 Science can be influenced by race, gender, nationality, or religion of the scientist. 13 Science involves dealing with many uncertainties. 14 Scientific concepts and discoveries can cause new problems for people. 15 Something that is "proven scientifically" is considered by scientists as being a fact, and therefore no longer subject to change. 16 Science requires a great deal of creative activity. 17 Disagreement between scientists is one of the weaknesses of science. Your Answer Correct Answer What is Science? • Science is… • Science involves… • Etc. http://mhrussel.files.wordpress.com/2013/01/untitled1.png What is NOS about? • What is science? • How do scientists do their work? • What is the nature of scientific knowledge? • How does scientific knowledge develop? • Is science objective? (What is objectivity?) • How does science differ from other ways of knowing? Study of NOS • The study of NOS is informed by: – Philosophy of Science – History of Science – Sociology of Science – Science Education What Should a Scientific Explanation Include? (Examples) What is a Scientific Explanation? http://www.referenceforbusiness.com/photos/hypothesis-testing-618.jpg What is a Scientific Explanation? • In common usage, an explanation is a statement made to clarify something and make it understandable. • In science, “explanation” means something more concrete. • Scientific explanations consist of three specific parts: 1. claims, 2. evidence, 3. and reasoning. CER What is a Scientific Explanation? • Define claim & evidence. • A claim is an assertion or conclusion that answers the original question. • Evidence is scientific data that supports the student’s/scientist’s claim. It must be appropriate and sufficient. It can come from an investigation or other source, such as observations, reading material, or archived data. What is a Scientific Explanation? • Define reasoning. • Reasoning is the justification that links the claim and evidence. It shows why the data counts as evidence to support the claim, using appropriate scientific principles. http://www.sci-news.com/paleontology/science-anzu-wylieidinosaur-01811.html 3.3 m (11 feet) tall 1.5 m (5 feet) tall at the hip BACK TO: The “Chicken from Hell” • Resembled a cross between a modern emu and a reptile. • Described from 3 specimens that collectively preserve almost the entire skeleton. • Paleontologists can study the anatomy and evolutionary relationships of a mysterious group of theropod dinosaurs known as caenagnathids (pronounced SEE-nuh-NAY-thids). • Researchers reported that two of the specimens display evidence of pathology. • One appears to have a broken and healed rib. • The other has evidence of some sort of trauma to a toe. http://scitechdaily.com/paleontologists-announcediscovery-bird-like-dinosaur-anzu-wyliei/ Lamanna MC, Sues H-D, Schachner ER, Lyson TR (2014) A New Large-Bodied Oviraptorosaurian Theropod Dinosaur from the Latest Cretaceous of Western North America. PLoS ONE 9(3): e92022. doi:10.1371/journal.pone.0092022 http://www.plosone.org/article/info:doi/10.1371/journal.pone .0092022 Figure 1. Exposures of the Upper Cretaceous Hell Creek and Lance formations in western North America. The specimens were excavated from the uppermost level of the Hell Creek rock formation in North and South Dakota – a formation known for abundant fossils of Tyrannosaurus rex and Triceratops. Figure 2. Craniomandibular skeleton of Anzu wyliei gen. et sp. nov. • The dinosaur would have resembled a gigantic flightless bird, more than a typical theropod dinosaur such as Tyrannosaurus rex. • It weighed an estimated 200 to 300 kg (440 to 660 pounds). Lamanna MC, Sues H-D, Schachner ER, Lyson TR (2014) A New Large-Bodied Oviraptorosaurian Theropod Dinosaur from the Latest Cretaceous of Western North America. PLoS ONE 9(3): e92022. doi:10.1371/journal.pone.0092022 http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092022 Anzu wyliei • Its jaws were tipped with a toothless beak, and its head sported a tall, rounded crest similar to that of a cassowary. Casuarius casuarius Figure 3. Photographs of craniomandibular elements of Anzu wyliei gen. et sp. nov. • With large sharp claws, Anzu wyliei was an omnivore, eating vegetation, small animals and perhaps eggs while living on a wet floodplain. The dinosaur apparently got into some scrapes. • Anzu wyliei is the largest oviraptorosaur found in North America • Oviraptorosaurs are a group of dinosaurs that are closely related to birds and often have strange, cassowary-like crests on their heads. Lamanna MC, Sues H-D, Schachner ER, Lyson TR (2014) A New Large-Bodied Oviraptorosaurian Theropod Dinosaur from the Latest Cretaceous of Western North America. PLoS ONE 9(3): e92022. doi:10.1371/journal.pone.0092022 http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092022 Figure 4. Postcranial skeleton of Anzu wyliei gen. et sp. nov. as preserved in the CM specimens. • More than a dozen oviraptorid species have been discovered, all in Mongolia and China, and many are known from beautifullypreserved, complete or nearly complete skeletons. • Additionally, beginning in the 1990s, several small, primitive relatives of oviraptorids were unearthed in much older, about 125 million-year-old rocks in northeastern China. Lamanna MC, Sues H-D, Schachner ER, Lyson TR (2014) A New Large-Bodied Oviraptorosaurian Theropod Dinosaur from the Latest Cretaceous of Western North America. PLoS ONE 9(3): e92022. doi:10.1371/journal.pone.0092022 http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092022 Figure 6. Strict consensus trees resulting from successive trials of phylogenetic analysis. • Paleontologists have established that caenagnathids, oviraptorids, and these more archaic Chinese species are closely related to one another, and have united them as the theropod group Oviraptorosauria. • Location of oviraptorosaurs in both Asia and North America is due to the fact that these continents were frequently connected during the Mesozoic Era, allowing dinosaurs and other land animals to roam between them. Lamanna MC, Sues H-D, Schachner ER, Lyson TR (2014) A New LargeBodied Oviraptorosaurian Theropod Dinosaur from the Latest Cretaceous of Western North America. PLoS ONE 9(3): e92022. doi:10.1371/journal.pone.0092022 http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092022 Figure 7. Calibrated phylogeny of oviraptorosaurian theropods showing hypothesized position of Anzu wyliei gen. et sp. nov. • Paleontologists have established that caenagnathids and oviraptorids, are closely related to one another, and have united them as the theropod group Oviraptorosauria. Lamanna MC, Sues H-D, Schachner ER, Lyson TR (2014) A New Large-Bodied Oviraptorosaurian Theropod Dinosaur from the Latest Cretaceous of Western North America. PLoS ONE 9(3): e92022. doi:10.1371/journal.pone.0092022 http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092022 Why new science standards? Why now? Standards Development Our last science standards were adopted in 1998 We know more about how people learn Emphasis has shifted, new advances http://www.nextgenscience.org/ Standards Development Organized by Achieve, Inc. but led by the states. California was one of 26 Lead States Multiple rounds of input on public and private drafts over an 18 month period State Review Team and Science Expert Panels convened to provide input and recommendations to State Superintendent of Public Instruction Tom Torlakson Shifts From Old to New Standards A marriage between the doing of science and the knowing of science Architecture is different Written in terms of how students will be assessed (Performance Expectations) Three Dimensions • Scientific and Engineering Practices • Crosscutting Concepts • Disciplinary Core Ideas Dimension 1 Science & Engineering Practices 1. Asking questions (science) and defining problems (engineering) 5. Using mathematics and computational thinking 6. Constructing explanations (science) and designing solutions (engineering) 2. Developing and using models 3. Planning and carrying out 7. Engaging in argument from evidence investigations 4. Analyzing and interpreting 8. Obtaining, evaluating, and communicating data information For each, the Framework includes a description of the practice, the culminating 12th grade learning goals, and what we know about progression over time. 15 Dimension 2 Crosscutting Concepts 1. Patterns 2. Cause and effect 3. Scale, proportion, and quantity 4. Systems and system models 5. Energy and matter 6. Structure and function 7. Stability and change 32 Dimension 3 Disciplinary Core Ideas Life Science Physical Science LS1: From Molecules to Organisms: Structures and Processes PS1: Matter and Its Interactions LS2: Ecosystems: Interactions, Energy, and Dynamics LS3: Heredity: Inheritance and Variation of Traits PS2: Motion and Stability: Forces and Interactions PS3: Energy PS4: Waves and Their Applications in Technologies for Information Transfer LS4: Biological Evolution: Unity and Diversity Earth & Space Science Engineering & Technology ESS1: Earth’s Place in the Universe ETS1: Engineering Design ESS2: Earth’s Systems ETS2: Links Among Engineering, Technology, Science, and Society ESS3: Earth and Human Activity Less emphasis on: Discrete Facts Isolated investigation and experimentation process skills Student acquisition of information Numerous Standards Uneven articulation throughout grade levels More emphasis on: Conceptual understanding with a focus on depth over breadth Integration of science and engineering practices with content Student understanding and use of scientific knowledge within and across science disciplines, and science and engineering practices Limited number of disciplinary Core Ideas and Cross Cutting Concepts that unify the study of science and engineering Learning progressions that develop K-12 *Presentation to the State Board of Education, July 10, 2013 Less emphasis on: No Engineering More emphasis on: Engineering standards and practices that all students should encounter Assessing science Assessing scientific understanding and knowledge reasoning specified by the performance expectations Limited correlation Correlation with CCSS ELA and with other subjects Mathematics Limited integration of Integration of science disciplines in science disciplines in middle school middle school *Presentation to the State Board of Education, July 10, 2013 Architecture of a Standard Performance Expectations Foundation Boxes Connection Boxes 1998 CA Kindergarten Life Science & Earth Science Students know how to observe and describe similarities and differences in the appearance and behavior of plants and animals NGSS Kindergarten Earth & Space Science Use a model to represent the relationship between the needs of different plants or animals (including humans) and the places they Students know characteristics live. (K-ESS3-1.) of mountains, rivers, oceans, valleys, deserts, and local landforms. 1998 CA 7th Grade Life Science Students know the function of the Umbilicus and placenta during pregnancy NGSS Middle School Life Science Use argument supported by evidence for how the body is a system of interacting Students know how bones subsystems composed of and muscles work together groups of cells. (MS-LS1to provide a structural 3.) framework for movement. 1998 CA High School Chemistry Students know how reaction rates depend on such factors as concentration, temperature, and pressure. NGSS High School Physical Science Apply scientific principles and evidence to provide an explanation about the effects of changing the temperature or concentration of the reacting particles on the rate at which a reaction occurs.(HS-PS1-5.) Appendices A B C D E F G H I J K L M Conceptual Shifts Responses to May Public Feedback College and Career Readiness All Standards, All Students Disciplinary Core Idea Progressions in the NGSS Science and Engineering Practices in the NGSS Crosscutting Concepts in the NGSS Nature of Science in the NGSS Engineering Design in the NGSS Science, Technology, Society, and the Environment Model Course Mapping in Middle and High School Connections to Common Core State Standards in Mathematics Connections to Common Core State Standards in English Language Arts The Nature of Science and NGSS The nature of science is included in the Next Generation Science Standards. Here we present the NOS Matrix. The basic understandings about the nature of science are: 1. Scientific Investigations Use a Variety of Methods 2. Scientific Knowledge is Based on Empirical Evidence 3. Scientific Knowledge is Open to Revision in Light of New Evidence 4. Scientific Models, Laws, Mechanisms, and Theories Explain Natural Phenomena 5. Science is a Way of Knowing 6. Scientific Knowledge Assumes an Order and Consistency in Natural Systems 7. Science is a Human Endeavor 8. Science Addresses Questions About the Natural and Material World Overview One goal of science education is to help students understand the nature of scientific knowledge. This matrix presents eight major themes and grade level understandings about the nature of science. Four themes extend the scientific and engineering practices and four themes extend the crosscutting concepts. These eight themes are presented in the left column. The matrix describes learning outcomes for the themes at grade bands for K-2, 3-5, middle school, and high school. Appropriate learning outcomes are expressed in selected performance expectations and presented in the foundation boxes throughout the standards. Understandings about the Nature of Science Categories Scientific Investigations Use a Variety of Methods K-2 3-5 Middle School High School Science investigations Science methods are determined Science investigations use a variety of methods and Science investigations use diverse methods and do not always use the Scientist use different Science investigations use a Science investigations are guided by a set of values New technologies advance scientific knowledge. Scientific inquiry is characterized by a common set of values that begin with a question. ways to study the world. by questions. variety of methods, tools, and techniques. tools to make measurements and observations. to ensure accuracy of measurements, observations, and objectivity of findings. Science depends on evaluating proposed explanations. Scientific values function as criteria in distinguishing between science and non-science. same set of procedures to obtain data. Scientific Knowledge is Based on Empirical Evidence Scientific Knowledge is Open to Revision in Light of New Evidence Science Models, Laws, Mechanisms, and Theories Explain Natural Phenomena Scientists look for patterns and order when making observations about the world. Science knowledge can change when new information is found. Scientists use drawings, sketches, and models as a way to communicate ideas. Scientists search for cause and effect relationships to explain natural events. Science findings are based on recognizing patterns. Scientists use tools and technologies to make accurate measurements and observations. Science explanations can change based on new evidence. Science theories are based on a body of evidence and many tests. Science explanations describe the mechanisms for natural events. Science knowledge is based upon logical and conceptual connections between evidence and explanations. Science disciplines share common rules of obtaining and evaluating empirical evidence. Scientific explanations are subject to revision and improvement in light of new evidence. The certainty and durability of science findings varies. Science findings are frequently revised and/or reinterpreted based on new evidence. Theories are explanations for observable phenomena. Science theories are based on a body of evidence developed over time. Laws are regularities or mathematical descriptions of natural phenomena. A hypothesis is used by scientists as an idea that may contribute important new knowledge for the evaluation of a scientific theory. The term "theory" as used in science is very different from the common use outside of science. include: logical thinking, precision, open-mindedness, objectivity, skepticism, replicability of results, and honest and ethical reporting of findings. The discourse practices of science are organized around disciplinary domains that share exemplars for making decisions regarding the values, instruments, methods, models, and evidence to adopt and use. Scientific investigations use a variety of methods, tools, and techniques to revise and produce new knowledge. Science knowledge is based on empirical evidence. Science disciplines share common rules of evidence used to evaluate explanations about natural systems. Science includes the process of coordinating patterns of evidence with current theory. Science arguments are strengthened by multiple lines of evidence supporting a single explanation. Scientific explanations can be probabilistic. Most scientific knowledge is quite durable but is, in principle, subject to change based on new evidence and/or reinterpretation of existing evidence. Scientific argumentation is a mode of logical discourse used to clarify the strength of relationships between ideas and evidence that may result in revision of an explanation. Theories and laws provide explanations in science, but theories do not with time become laws or facts. A scientific theory is a substantiated explanation of some aspect of the natural world, based on a body of facts that has been repeatedly confirmed through observation and experiment, and the science community validates each theory before it is accepted. If new evidence is discovered that the theory does not accommodate, the theory is generally modified in light of this new evidence. Models, mechanisms, and explanations collectively serve as tools in the development of a scientific theory. Laws are statements or descriptions of the relationships among observable phenomena. Scientists often use hypotheses to develop and test theories and explanations. Understandings about the Nature of Science Categories Science is a Way of Knowing K-2 Science knowledge helps us know about the world. 3-5 Science is both a body of knowledge and processes that add new knowledge. Science is a way of knowing that is used by many people. Middle School Science is both a body of knowledge and the processes and practices used to add to that body of knowledge. Science knowledge is cumulative and many people, from many generations and nations, have contributed to science knowledge. Science is a way of knowing used by many people, not just scientists. High School Science is both a body of knowledge that represents a current Scientific Knowledge Science assumes natural Assumes an Order and events happen today as Consistency in Natural they happened in the Systems past. Many events are repeated. Science is a Human People have practiced Endeavor science for a long time. Men and women of diverse backgrounds are scientists and engineers. Science Addresses Questions About the Natural and Material World. Scientists study the natural and material world. Science assumes consistent patterns in natural systems. Basic laws of nature are the same everywhere in the universe. Men and women from all cultures and backgrounds choose careers as scientists and engineers. Most scientists and engineers work in teams. Science affects everyday life. Creativity and imagination are important to science. Science assumes that objects and events in natural systems occur in consistent patterns that are understandable through measurement and observation. Science carefully considers and evaluates anomalies in data and evidence. Men and women from different social, cultural, and Scientific knowledge is a result of human endeavor, imagination, and Individuals and teams from many nations and cultures have Science findings are limited to what can be answered with empirical evidence. understanding of natural systems and the processes used to refine, elaborate, revise, and extend this knowledge. Science is a unique way of knowing and there are other ways of knowing. Science distinguishes itself from other ways of knowing through use of empirical standards, logical arguments, and skeptical review. Science knowledge has a history that includes the refinement of, and changes to, theories, ideas, and beliefs over time. Scientific knowledge is based on the assumption that natural laws operate today as they did in the past and they will continue to do so in the future. Science assumes the universe is a vast single system in which basic laws are consistent. ethnic backgrounds work as scientists and engineers. Scientists and engineers rely on human qualities such as persistence, precision, reasoning, logic, imagination and creativity. Scientists and engineers are guided by habits of mind such as intellectual honesty, tolerance of ambiguity, skepticism and openness to new ideas. Advances in technology influence the progress of science and science has influenced advances in technology. Scientific knowledge is constrained by human capacity, technology, and materials. Science limits its explanations to systems that lend themselves to observation and empirical evidence. Science knowledge can describe consequences of actions but is not responsible for society’s decisions. Nature of Science understandings most closely associated with Practices Nature of Science understandings most closely associated with Crosscutting Concepts creativity. contributed to science and to advances in engineering. Scientists’ backgrounds, theoretical commitments, and fields of endeavor influence the nature of their findings. Technological advances have influenced the progress of science and science has influenced advances in technology. Science and engineering are influenced by society and society is influenced by science and engineering. Not all questions can be answered by science. Science and technology may raise ethical issues for which science, by itself, does not provide answers and solutions. Science knowledge indicates what can happen in natural systems—not what should happen. The latter involves ethics, values, and human decisions about the use of knowledge. Many decisions are not made using science alone, but rely on social and cultural contexts to resolve issues. California’s Timeline September 4, 2013 State Board of Education adopted NGSS November 6, 2013 SBE adopted an integrated model as the preferred approach for middle school (a discipline focus model approved as an alternative) Jan-Feb 2014 Science Framework Focus Groups and Public Comment April 2014 – deadline to apply to serve on Framework Committee July 2014 Science Framework Development Begins 2014 Science Assessment Stakeholder meetings 2016 anticipated adoptions of California Science Framework 2015-16 (more likely 2016-17) implementation of NGSS in schools 2016-17 Instructional Materials Adoption Process Where to get more information NGSS website: www.nextgenscience.org/ CSTA website: www.cascience.org/csta/ngss.asp Consider joining the NGSS listserv hosted by CED or the NGSS Blog on the CSTA website Check out the CSTA calendar of events to find NGSS review workshops NSTA’s NGSS website www.nsta.org/about/standardsupdate/default.aspx Framework – available as PDF or for purchase www.nap.edu/catalog.php?record_id=13165 CEDWorkshops at the CSTA Conference: http://www.cascience.org/csta/pdf/ConferenceHandouts/2013/Boyd_Fram ework.pdf (Framework Timeline) http://www.cascience.org/csta/pdf/ConferenceHandouts/2013/Lafontaine _NGSSTheBasics.pdf (NGSS Basics) 45 The Link Between Dinosaurs and Birds • When scientists encounter a new specimen, part of their research is to observe, describe, and identify it. In part, the identification process happens by following an extremely detailed checklist marking the presence or absence of particular characters. • Examining the patterns of the appearance and disappearance of characters is the key to figuring out the relatedness of organisms. The Link Between Dinosaurs and Birds • Compare at least three specimens each from Dinosaur Hall and from the Hall of Birds. Begin to think about the relative relatedness of these specimens by examining the various features you observe. • In addition to these characters, hints about the identity of each specimen can be found by observing: • the body plan and posture (e.g. bipedal, more of a horizontal or vertical stance) • the relative length of arms to body size • the bones in the hands and fingers (separate or fused together) • the length and structure of the tail • the presence or absence and orientation of toes 1 and 5 on the foot • the presence or absence of teeth • the shape of the breastbone and extent to which sternum is keeled Analysis and Hypothesis • The following questions may help you begin to analyze and hypothesize about the relatedness of the specimens: 1. Which characters do they all share? 2. Which characters do some specimens share but not others? 3. Are some of these specimens more closely related to each other? Scientific Claims • Overwhelming evidence indicates that birds are a group of dinosaurs (avian theropod dinosaurs) that escaped the massive extinction 65 million years ago. • Birds share many anatomical characteristics with their extinct relatives. • Many characteristics present in their theropod ancestors were modified to enable birds to fly. Scientific Claim: Birds Evolved from Dinosaurs Dinosaur Hall • Dinosaur Hall at the Natural History Museum of Los Angeles, is one of the most extraordinary dinosaur exhibits in the world. • Inside are more than 300 real fossils, and 20 complete dinosaurs and ancient sea creatures. http://www.nhm.org/site/explore-exhibits/permanent-exhibits/dinosaur-hall Dinosaur Hall Exploration: 1.) Claim: Birds Evolved from Dinosaurs. 2.) Visit Dinosaur Hall at the Natural History Museum of Los Angeles, which is one of the most extraordinary dinosaur exhibits in the world. Inside are more than 300 real fossils, and 20 complete dinosaurs and ancient sea creatures. 3.) Provide as much evidence as you can from Dinosaur Hall to support the aforementioned claim “Birds Evolved from Dinosaurs.” 4.) Provide the reasoning behind each piece of evidence your group collected to support the claim. Ralph W. Schreiber Hall of Birds • This hall presents an incredibly diverse selection of birds from all over the world, with examples of more than 400 species that are local to Southern California. Great Auk Pinguinus impennis Cassowary http://www.nhm.org/site/explore-exhibits/permanent-exhibits/birds Ralph W. Schreiber Hall of Birds 1.) Claim: Birds Evolved from Dinosaurs. 2.) Visit the Ralph W. Schreiber Hall of Birds at the Natural History Museum of Los Angeles. This hall presents an incredibly diverse selection of birds from all over the world, with examples of more than 400 species that are local to Southern California. 2.) Provide as much evidence as you can from Hall of Birds to support the aforementioned claim “Birds Evolved from Dinosaurs.” 3.) Provide the reasoning behind each piece of evidence your group collected to support the claim. Provide examples from the Dinosaur Hall and Hall of Birds Exhibits to support… • The Nature of Science in the NGSS • Choose a particular Grade Level (K-12) and apply as many of the NGSS/NOS categories to the exhibit as possible. • Be sure to provide at least one example from the exhibit per category. • Design/apply a lesson plan to support your findings. Resources • Next Generation Science Standards www.nextgenscience.org/ • CDE updates to the NGSS www.cde.ca.gov/pd/ca/sc/ngssintrod.asp • http://www.cde.ca.gov/pd/ca/sc/ngssstandard s.asp • NSTA Common Core Resources www.nsta.org/about/standardsupdate Scientific Hypothesis, Law, Theory, and Fact • What is a Fact? • What is a Hypothesis? • What is a Law? • What is a Scientific Theory? FACTS • Fact: Facts are the objects and events that exist around us, which we might observe and experience. • Facts or shared empirical observations are the foundation upon which all scientific knowledge is constructed, but what scientists do with those facts is key to a complete understanding and appreciation of the scientific enterprise (Fitzhugh 2009). Scientific Fact • Fact: In science, an observation that has been repeatedly confirmed (NRC, 1998). How Can FACTS be Used in Science? • In brief, facts or shared data and observations are the raw materials of science that may be used in a variety of ways. • Facts may be formed into a law or “a descriptive generalization about how some aspect of the natural world behaves under stated circumstances” (National Academy of Sciences (NAS), 1998, p. 5). Another distinct kind of scientific knowledge is a theory which is “a well substantiated explanation of some aspect of the natural world that can incorporate facts, laws, inferences, and tested hypotheses” (p. 5). How Can FACTS be Used at the NHM LA? American black bear Ursus americanus (Pallas, 1780) http://www.nhm.org/site/explore-exhibits/permanent-exhibits/northamerican-mammals/black-bear • For instance, we have the facts that mammals have hair—a set of observations we wish to explain (Fitzhugh 2009). HYPOTHESIS • How would you incorporate the aforementioned fact(s) into a hypothesis? • An evolutionary biologist might then present the following hypothesis: • As the result of random mutation, hair originated in the earliest mammals, which were diminutive and likely nocturnal creatures, living among the dinosaurs, and there was a selective advantage to the presence of hair because it ensured a constant body temperature. Scientific Hypothesis • Hypothesis: A testable statement about the natural world that can be used to build more complex inferences and explanations (NRC, 1998). • A hypothesis in the classroom or museum setting usually involves a prediction followed by an explanation. • Hypotheses suggest to us what might have happened in the past to account for what we observe in the present. http://assets.baymard.com/blog/ab-testing-problem-hypothesisfull-size.png Scientific Law vs. Theory • In the language of science, laws and theories are related but distinct kinds of scientific knowledge. Scientific Law vs. Theory • Laws and theories are both products and tools of science, but each has a distinct heritage and role. One does NOT become the other when more evidence is amassed (Horner & Rubba, 1978, 1979; McComas, 1997). • Theories and laws are equally mature, important, useful and unique kinds of scientific knowledge. Understanding the fundamental distinctions and relationships between laws and theories is essential in fully appreciating and evaluating the work of scientists while gaining fluency in the language of science. https://pbs.twimg.com/profile _images/1384598458/PolarBear-6108-crop.jpg http://cbsla.files.wordpress.com/2012/11/natural-history-museum.jpg • The Natural History Museum of Los Angeles can provide the opportunity for students to understand the roles and discrete contributions of laws and theories while providing opportunities for them to question their beliefs about these and other related issues in the nature of science. • Theories, on the other hand, are used to not only guide us in understanding the present by way of the past, but to also anticipate what we might experience in the future. • As with any human endeavor, however, hypotheses and theories might be incorrect. So a fundamental part of any field of science is the process of critically evaluating our hypotheses and theories, known as testing. http://us.123rf.com/400wm/400/400/radiantskies/radiantskies1212/radiantskie s121200432/16632227-abstract-word-cloud-for-scientific-theory-with-relatedtags-and-terms.jpg Scientific Law • Law: A descriptive generalization about how some aspect of the natural world behaves under stated circumstances (NRC, 1998). Laws include predictions made about natural phenomena. Scientific Theory • Theory: A well-substantiated explanation/mechanism of some aspect of the natural world that can incorporate facts, laws, inferences, and tested hypotheses (NRC, 1998). Theories explain how the law works (McComas, 2003). • Scientific theories are explanations that are based on lines of evidence, enable valid predictions, and have been scientifically tested in many ways. http://www.physicalgeography.net/fundamentals/images/under1.GIF http://www.projectrho.com/public_html/rocket/images/respectscience/theory.jpg Scientific Law vs. Theory • Sonleitner, (1989) makes the point that theory and law, are qualitatively different in what they are and what they do. • He states that laws are generalizations about phenomena while theories are explanations of phenomena. • Theory and law are not distinguished by their degree of verification. Core NOS Ideas to Inform K-12 Science Teaching • The following NOS ideas are emerging as the consensus elements that should define the content core when NOS is taught as content in K-12 educational programs. 1) Science demands and relies on empirical evidence. 2) Knowledge production in science shares many common factors such as shared habits of mind, norms, logical thinking and methods (including careful data recording, truthfulness, observation, etc.) • However, there is no one scientific methods by which all science is done • Experiments are not the only route to knowledge • Science uses both inductive reasoning and hypothetico-deductive testing • Scientific conclusions are peer reviewed but observations and experiments are not generally repeated 3) Scientific knowledge is tentative but durable. (This means that science cannot prove anything but scientific conclusions are still valuable and long lasting) • The problem of induction makes ultimate “proof” impossible Consensus Views on NOS (cont’d) 4) Laws and theories are related but distinct kinds of scientific knowledge. Hypotheses are special, but general, kinds of scientific knowledge (and the term probably causes more problems then it is worth). 5) Science has a creative component. 6) Science has a subjective element. (Ideas and observations in science are “theory”-laden; this bias plays both potentially positive and negative roles in scientific investigation). Consensus Views on NOS (cont’d) 7) There are historical, cultural and social influences on science. 8) Science and technology impact each other, but they are not the same. 9) Science and its methods cannot answer all questions. (In other words, there are limits on the kinds of questions that can be asked of science. There is no conflict between science and religion). This list has been developed with reference to sources including McComas, Clough and Almazroa (1998), McComas and Olson (1998), Lederman, et al (2002) and Osborn, et al (2003). References Allen, G. and J. Baker. 2001. Biology: Scientific Process and Social Issues. Bethesda, Md.: Fitzgerald Science Press, Inc. Bybee, R. W. (Ed.) 2004. Evolution in Perspective: The Science Teacher’s Compendium. Arlington, VA: NSTA Press. Campbell, N.A., Reece, J.B., and Mitchell, L.G. 1999. Biology (5th ed.). Menlo Park, CA: Benjamin Cummings. Darwin, C. 1964. On the Origin of Species (Facsimile 1st ed.). Cambridge, MA: Harvard University Press. Freeman, S. & Herron, J.C. 2004. Evolutionary analysis (3rd. Ed). Upper Saddle River, NJ: Pearson/Prentice Hall. Gould, J.A. 1992. Classical Philosophical Questions. 9th ed. Upper Saddle River, N.J.: Prentice Hall. Miller, K.R. 2006. Presentation. NSTA Conference. Anaheim, CA. Miller, K. R. 1999. Finding Darwin’s God. New York, NY: Harper Collins. Narguizian, P. 2004. Understanding the nature of science through evolution. The Science Teacher 71(9): 40-45. National Academy of Sciences. (2004). Evolution in Hawaii: A Supplement to Teaching About Evolution and the Nature of Science, by Steve Olson. Washington, DC: The National Academies Press. National Research Council. 1996. National Science Education Standards. Washington, DC: National Academy Press. Pennock, R.T. (2005). On teaching evolution and the nature of science. In J. Cracraft & R.W. Bybee (Eds.), Evolutionary science and society: Educating a new generation (pp.7-12). Washington, DC: AIBS/BSCS. Peterson, G. R. 2002. The intelligent design movement: Science or ideology? Zygon 37(1): 7-23. Price, P.W. (1996). Biological evolution. New York: Saunders College Publishing. Scott, E.C. (2005). Evolution vs. creationism. Berkeley, CA: University of California Press. University of California Museum of Paleontology at UC Berkeley and the National Center for Science Education: evolution.berkeley.edu/evosite/evohome.html Volpe, E.P. & Rosenbaum, P.A. (2000). Understanding evolution. New York: McGraw Hill. Key Concepts • A scientific theory is an explanation inferred from multiple lines of evidence for some broad aspect of the natural world and is logical, testable, and predictive. As new evidence comes to light, or new interpretations of existing data are proposed, theories may be revised and even change; however, they are not tenuous or speculative. • A scientific hypothesis is an inferred explanation of an observation or research finding; while more exploratory in nature than a theory, it is based on existing scientific knowledge. • A scientific law is an expression of a mathematical or descriptive relationship observed in nature. It also has predictive power. • VTShome.org • Visual literacy & Science Literacy (connections)… • Observation(s)/Claims/Evidence/ Reasoning • Nhm.org