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Fossils. Presented by Linder O. Winter E-S Rules Committee Modified by Neil Michels (MSO). SESSION OBJECTIVES. Introduce the 2010 Fossils Event rules ( short-cut ) Suggest options and strategies to guide participants in preparing for the event ( short-cut )

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  1. Fossils Presented by Linder O. Winter E-S Rules Committee Modified by Neil Michels (MSO)

  2. SESSION OBJECTIVES • Introduce the 2010 Fossils Event rules (short-cut) • Suggest options and strategies to guide participants in preparing for the event (short-cut) • Address major topics and themes included in the event (short-cut) • Review a recent exam (take quiz)

  3. 2010 EVENT RULES • DESCRIPTION: Teams will demonstrate their knowledge of ancient life by completing several tasks at a series of stations.

  4. DESCRIPTION: Continued • Emphasis will be on fossil identification and ability to answer questions about: • Classification • Habitat • Ecologic relationships • Behaviors • Use of fossils to date and correlate rock units

  5. A TEAM OF UP TO: 2 • Roles of each team member should be defined long before the competition. • Lead participant: most knowledgeable and/or most experienced • Avoid limiting participation to only two members due to potential drop-outs, illness, conflicting times, etc. • Don’t discount younger students, i.e. sixth graders • Avoid identifying team members too quickly

  6. EVENT PARAMETERS • Each team may bring only one magnifying glass. • Emphasis is on the word team • Controls the number of objects to transport from station to station

  7. EVENT PARAMETERS:Field Guides • One published field guide that they may tab, write in or attach Post-It or other notes • Recommend that participants consult one or more field guides and numerous books and websites while developing their binder • Suggest that participants not bring field guides to the competition

  8. EVENT PARAMETERS:Field Guides • Why not bring a field guide? • Participants are given only a very brief time at each station • Contains far too much information to sort through in a very short time • Often serves as a crutch rather than an effective resource

  9. EVENTPARAMETERS:3-Ring Binders • And one 3-ring binder (any size) containing information in any form from any source. The materials must be 3-hole punched and inserted into the rings (sheet protectors are allowed). • Teammates work together to create the binder. This encourages discussions on items to include and provides an opportunity to actually work together as a team.

  10. EVENTPARAMETERSRationale for Permitting Resources • Most professionals take field guides with them into the field. • For Science Olympiad participants, resources … • Provide a means for coaches to monitor participant progress • Include only those items identified in the event rules • Are uniquely developed by the competitors • Encourage preparation

  11. 3 – RING BINDERCreating the Ideal Resource • Each team of individuals should create their own binder. • Binders “grow” as team members’ knowledge and experience grow. • It’s the creation and continual upgrading of one’s own binder that make them such an effective tool. • Avoid the temptation to pass binders on to future teams!

  12. 3 - RING BINDER:Table of Contents • Suggest participants obtain a notebook with clear plastic sleeves on both front and rear covers. • Create “cover sheets” with names and thumbnail images of each specimen along with page numbers where specimens are found to insert into the plastic covers. • Front – invertebrates. Rear – vertebrates and plants • “Speed is the key!” Design for rapid specimen identification to permit maximum time for locating requested information. • Devote one page to each specimen. Standardize format for quick and easy access.

  13. 3-Ring Binder: Items to include on pages devoted to each specimen • Repeat thumbnail image, if desired • Mode of life, i.e. predator, scavenger … • Environment • Special adaptations for survival – food gathering, defense, etc. • Position on the Geologic Time Scale • Taxonomic classification • Labeled sketches identifying various body features • Significance of the creature to paleontology, i.e. index fossil, etc. • Names, and possibly images, of related specimens

  14. 3 - RING BINDERAdditional Materials – Appendix • Glossary of key terms • Geologic Time Scale • Listing of major events that occurred during each era or period, i.e. mass extinctions, introduction of new species, etc. • Descriptions of common fossil-bearing sedimentary rocks … high or low energy environments; highlands or adjacent plains, etc. • Types of fossilization … descriptions and examples

  15. 3 - RING BINDERContinual Maintenance • Team briefings following each level of competition • Identify difficulties or surprises participants may have encountered during the competition • Modify binder to include facts and concepts that would have been helpful had they been included • Additional information obtained through continued study and research

  16. 3-Ring Binder: Previously Administered Exams • Sources: National and State Science Olympiad sites, Coaches Clinics, etc. • Science Olympiad Student Center located at http://scioly.org/wiki/Fossils#Sample_Questions (now includes the former Wright Center materials listen under “Outside Resources.”) • Have participants review previously administered exams for information that may prove beneficial during future events.

  17. INTERNET RESOURCES Limit visits to professional sites only! • USGS • College Sites – Geology and Paleontology Departments • National Parks and Monuments • Science Olympiad Student Center • Many commercial sites often include good information about the fossils they sell.

  18. INTERNET RESOURCES Avoid websites posted by individuals or organizations with an agenda • Creation Science websites. • It’s inevitable that participants will stumble onto these sites which advocate two major worldwide events, the Creation and the Great flood as the sole events that influenced early life on Earth.

  19. Suggested Resource for C-Division • This is a remarkable book for students interested in the history of paleontology. • Author: Sean B. Carroll

  20. THE COMPETITION • Emphasis will be placed upon task-oriented activities. • Participants will move from station to station, with the length of time at each station predetermined and announced by the event supervisor. • Participants are not permitted to return to stations, but may alter or add information to their original responses while at other stations. • Identification will be limited to species on the list, but other species may be used to illustrate key concepts.

  21. Supervisor Philosophies Prepare participants for different types of exams: • “Old-school” individuals tend to design knowledge-based exams. • Others prefer a mixture of conceptionally-based activities with knowledge content.

  22. SPECIMEN COLLECTIONS • Don’t be disappointed when you discover that kits including all the specimens on the SO list simply are not available • Before purchasing specimens, inventory those your school may already have or consult with the previous coach from your school. • Start small and add to your collection as budget and availability permit • Think twice before purchasing inexpensive kits offering a large number of specimens at a very low cost. Most include small and/or broken specimens having little value other than simple identification.

  23. SPECIMEN COLLECTIONS • Larger specimens showing greater detail are ideal • Images of specimens, although less than ideal, are fair substitutes. • Many commercial websites provide quality images of specimens.

  24. SPECIMEN COLLECTIONS Try to include replicas of ancient creatures in your collections. Supervisors may include questions about special adaptations, such as a mammoth’s tusks used to shove aside snow, carnivores vs. herbivores, etc.

  25. SPECIMEN COLLECTIONS • The Fossils Event is on a three-year rotational scheme, with Rocks and Minerals as its counterpart. • Plan purchases to span over a period of several years to spread cost. • Emphasize the importance of treating specimens with care, returning them to designated storage areas, etc. • Visit www.otherworlds-edu.comfor quality speci-mens at a very “reasonable” cost.

  26. VOLUNTEERS • As with all events of the Science Olympiad, practicality often dictates identifying a volunteer to coach this event. • If you are unable to obtain a professional or amateur volunteer, attempt to seek out an interested parent or community member. Many parents are willing to devote numerous hours to help their own children, as well as those of their friends and classmates, achieve their greatest potential. • A background in paleontology is not an absolute essential, but strong interest is. • Professionals often enjoy sharing their passion for fossils with others – especially with children.

  27. VOLUNTEERS • Provide a copy of this PowerPoint presentation to your volunteer(s) as very few are familiar with the coaching regimen. Provide an opportunity to follow-up on any questions your volunteer may have. • Touch base with your volunteer(s) frequently to assure that they are following through on their commitment and are comfortable with their role. • A few of these volunteers become so involved that they volunteer to assist with other events, provide assistance at competitions, or even continue their role after their own children have moved on.

  28. COACHING STRATEGIES • Monitor development of participant binders. This is especially beneficial if a large number of individuals have shown an interest in this event. • Competitive rivalry increases the chances of constructing the best overall team possible.

  29. COACHING STRATEGIES • Set up weekly practice sessions with three to five stations each. Stations included in previously administered exams makes this task a bit easier. • The initial sessions can be untimed. After several weeks, set time limits of three to five minutes per station to simulate actual competitive conditions. • It’s much better for participants to experience “pressure” under simulated conditions than during actual competitions. • Practice drills are also valuable. Compile a list of questions; dictate them orally; clock the time required for participants to locate the answers in their notebooks; and note their accuracy.


  31. Suggested Reference • The following reference was invaluable as a resource for developing many of the following slides. It is a HIGHLY recommended resource for both B- and C-Division Science Olympiad participants. Its explanations are concise and thorough. It addresses many crucial concepts often ignored by other books. Its illustrations are both beautiful and functional. • Coenraads, Robert R., Rocks and Fossils – A Visual Guide. Firefly Books, Ltd., 2005 • ISBN-13: 978-1-55407-068-8 • ISBN-10: 1-55407-068-6

  32. TOPIC A: CONDITIONS FOR FOSSILIZATION TO OCCUR • Rapid burial to (a) avoid scavenging and (b) eliminatating oxygen to prevent decay • Possession of hard parts - bones, teeth, nails, shell or woody tissue

  33. TOPIC B: MODES OF PRESERVATION - PERMINERALIZATION • Skeletal material can be quite porous. If the pores are filled in by foreign minerals that precipitate out of solution, the fossil is said to be permineralized. • Petrified wood is an example of wood that has been permineralized by silica.

  34. TOPIC B: MODES OF PRESERVATION: PETRIFACTION/PETRIFICATION/SILICIFICATION • In geology, petrifaction, petrification or silicification is the process by which organic material is converted into stone by impregnation with silica.

  35. TOPIC B: MODES OF PRESERVATION – MINERAL REPLACEMENT • This occurs when skeletal material is replaced, molecule by molecule, with some alien material. • This process occurs gradually over a long period of time as the original mineralogy dissolves away and a new mineral precipitates in its place. Examples include: • (1) Silicification - when calcium carbonate is replaced by silica, and • (2) Pyritization - a permineralization process involving sulfur and iron.

  36. TOPIC B: MODES OF PRESERVATION: CASTS & MOLDS • Sometimes the original material is dissolved away, leaving a cavity in the rock which may later become filled with another material, such as a mineral. • The cavity is known as a mold • The internal filling is known as a cast

  37. TOPIC B: MODES OF PRESERVATION: IMPRINT • Carbonization occurs when all organic volatiles are distilled away due to the effects of heat and/or pressure, leaving a carbon film remnant of the organism. • This usually occurs with organisms rich in carbon that possess thin or no skeletal material.

  38. TOPIC B: MODES OF PRESERVATION: ACTUAL REMAINS • Unaltered: Occasionally an organism's skeleton is preserved intact without any chemical alteration of the original mineralogy. • This mode of preservation becomes increasingly rare for fossils of older ages. • Note: Copal has been added to the Official NSO List as it is cheaper and fills the same role as amber which is much more expensive.

  39. TOPIC B : UNCOMMON MODES OF PRESERVATION • Uncommon modes of preservation: • Encasement in amber or copal – smaller animals, mainly insects, but sometimes lizards, frogs and birds • Mummification – rare process peculiar to desert areas • Freezing – animals, including humans and mammoths • Entrapment – in tar/asphalt

  40. TOPIC C: RELATIVE DATING • The most basic concept used in relative dating is the law of superposition. • Simply stated, each bed in a sequence of sedimentary rocks (or layered volcanic rocks) is younger than the bed below it and older than the bed above it. • This law follows two basic assumptions: (1) the beds were originally deposited horizontally and (2) the beds were not overturned after their deposition.

  41. TOPIC C: RELATIVE DATING • The principle of cross-cutting relationships states that the geologic feature which cuts another is the younger of the two features, i.e. the thing being cut is older than the thing doing the cutting.

  42. TOPIC C: RELATIVE DATING • Unconformities: buried erosion surfaces

  43. TOPIC C: RELATIVE DATING • The law of faunal succession states that groups of fossil animals and plants occur throughout the geologic record in a distinct and identifiable order. • Following this law, sedimentary rocks can be "dated" by their characteristic fossil content. • Particularly useful are index (zonal) fossils, geographically widespread fossils that evolved rapidly through time. • Reference for this and preceding slide: Utah Geological Survey

  44. TOPIC D: ABSOLUTE DATING • Carbon dating uses the half-life of Carbon-14 to find the approximate age of certain objects that are 40,000 years old or younger. • The ratio of normal carbon (carbon-12) to carbon-14 in the air and in all living things at any given time is nearly constant. • One in possibly a trillion carbon atoms is carbon-14. Both Carbon-12 and Carbon-13 are stable, but Carbon-14 decays by very weak beta decay to nitrogen-14 with a half-life of approximately 5,730 years. After the organism dies it stops taking in new carbon. http://www.ndt-ed.org/EducationResources/HighSchool/Radiography/carbon14dating.htm

  45. TOPIC D: ABSOLUTE DATING • Radioactive decay is the process by which a "parent" isotope changes into a "daughter" isotope. • Rates of radioactive decay are constant and measured in terms of half-life, the time it takes half of a parent isotope to decay into a stable daughter isotope.

  46. TOPIC D: ABSOLUTE DATING • Some rock-forming minerals contain naturally occurring radioactive isotopes with very long half-lives unaffected by chemical or physical conditions that exist after the rock is formed. • Half-lives of these isotopes and the parent-to-daughter ratio in a given rock sample can be measured • Then a relatively simple calculation yields the absolute (radiometric) date at which the parent began to decay, i.e., the age of the rock.

  47. TOPIC D: ABSOLUTE DATING Volcanic Ash • Volcanic ash is one of the best materials for absolute dating because it can be used for both radiometric dating and absolute dating. • Geologically, volcanic events are relatively instantaneous events. • Any fossils found above, below, or between can be dated “relative” to the volcanic ash layers.


  49. TOPIC F: INDEX FOSSILS –CRITERIA • An index or zonal fossil is any fossil that may be used for correlating and dating geologic strata found in different parts of the world. • A perfect index fossil will satisfy all the following criteria:

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