Fossilization By: Lee Falkena Adapted By: Braden Conrad-Hiebner & Cherie Haury-Artz

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1 Topic/Unit - Fossil formation Grade Level Iowa Science Standards - Fossilization By: Lee Falkena Adapted By: Braden Conrad-Hiebner & Cherie Haury-Artz 3-LS4-1. Analyze and interpret data from fossils to provide evidence of the organisms and the environments in which they lived long ago. MS-LS4-1. Analyze and interpret data for patterns in the fossil record that document the existence, diversity, extinction, and change of life forms throughout the history of life on Earth under the assumption that natural laws operate today as in the past. Introduction This unit is a pre-activity for students to complete before visiting the Delving Deep: Scientific Discoveries from Iowa s Ancient Sea! exhibit in the University of Iowa Mobile Museum. The purpose of this activity is for students to experience the creation of trace and permineralized fossils that were found in the Winneshiek Lagerstätte near Decorah, Iowa. Students will take a journey on the road to becoming a fossil. However, not all students will become fossils, showing that 1) not every animal will be represented in the fossil record and 2) that certain animals are more suited to becoming fossils because of their abundant hard parts or particular living environment. About the exhibit: Researchers from the Iowa Geological Survey at the University of Iowa discovered evidence that a meteorite struck the earth near what is now the town of Decorah in Winneshiek County, Iowa. This event took place during the Ordovician Period, 465 million years ago. The meteorite created a crater in the earth s crust estimated to have been 3.5 miles in diameter and several hundred meters deep. The crater was flooded by a tropical seaway, creating the unusual environment that allowed for the spectacular preservation of marine fossils. In some cases, even soft bodies or tissues were preserved. These fossils provide important new information about the creatures which inhabited this ancient tropical sea and their living environment.

2 Instructional Objectives 1. Begin the pre-activities three to five days before the main activity allowing time for both the trace and permineralized fossils to harden. 2. Students travel to various locations on the fossil timeline and experience different processes in the fossilization process, creating an understanding of fossilization and its relationship to specific environments 3. Students present information about the potential for fossilization of their group's species, recreating the scientific process of communication and cooperation. 4. Students observe that fossils are not always preserved in every environment and that the fossil record is not an accurate representation of the flora and fauna of a particular environment as many species may not be preserved in the rock record Major Concepts Trace fossils and permineralized fossils are two kinds of fossils that provide scientists with information about prehistoric plant and animal life on earth. Specific environments lend themselves to excellent fossil records. Hard parts are the primary part of an animal or plant that will be fossilized; however, soft parts may be preserved in certain areas in what are known as "Lagerstatten" deposits. Not every animal is fossilized due to the environment or bodily composition, making an incomplete fossil record of prehistoric flora and fauna Materials & Equipment Pre-Activity #1 - sponge, scissors, salt, water, sand Pre-Activity #2 - salt, flour, coffee, wax paper, mixing bowl, mixing spoon, measuring cup Primary Activity - 14 dice, poster paper, crayons/colored pencils/markers Instructional Activities Pre-Activity #1* (5-10 minutes) *Begin the activity 3-5 days before the lesson plan. This will allow the sponge to undergo fossilization. Lesson Objective: This activity illustrates how permineralized fossils form. Permineralized fossils are formed by mineral rich water from the ground, lakes, or ocean that fill the pore spaces of a bone, shell, or plant. Internal crystals are formed that eventually turn the whole object into rock. If available, provide students with broken chicken or turkey bones to examine with a hand lens and identify the pore openings. Gather the items you ll need for the activity: o Sponge scissors, salt, water, sand Cut your fossil out from the sponge

3 o It can be whatever shape you want Add 100 g of salt to 250 ml of warm water and stir the mixture Add enough sand to fill a bowl at least half full Place your sponge fossil into the sand and cover it Make sure the sponge is not visible Add the salt water mix on top of the sand Place the bowl near a windowsill or warm place and let dry for 3-5 days Check on your fossils until they are hard and dry Pre-Activity #2* * Begin the activity 3-5 days before the lesson plan. This will allow the mixture to harden. Lesson Objective: This activity illustrates how trace fossils form. Trace fossils are not the same as bone fossils, because the actual object does not remain as the fossil. Something like a foot, skin, feather, leaf, bug, or shell gets pushed into a soft substance, like mud, and creates an impression before it hardens. If the material becomes buried and undergoes enough pressure, it can be turned into rock and impressions are preserved as trace fossils. Gather the materials you ll need for this activity Salt, flour, coffee, coffee grounds, mixing spoons, mixing bowls, wax paper Mix together 1 cup salt. 3 cups flour, 1 cup cold brewed coffee, and 2 cups used coffee grounds in mixing bowl. Stir well until the mixture is smooth. Add additional flour if consistency is too drippy. Spread dough out on wax paper, flatten with hands, and break off enough pieces for each student. Make sure students have their own piece of wax paper to work on. Have students flatten their dough onto their wax paper to about the thickness of a chocolate chip cookie. Have students take the object of their choosing and push it into the dough. Remove object carefully and slowly. Allow the impression to dry (2-5 days). Oven baking is discouraged, as it often results in cracking. Day#1 Opener (10-15 minutes): Have students collect their trace and permineralized fossils and: o State that they will have one to two minutes to write their observations individually (collect them at the end of this discussion). o After they have had a moment to look and touch the specimens and write down their observations, have the students pair up to explain their observations. o Come back together and have each table share their observations to the class. If their sharing has not revealed some of the following information, try some of these questions in order to get the students to think about fossilization: o What happened?

4 Permineralized Fossils: When the salt water was added to the sand, it filled the pores of the sponge. When the water evaporated, the salt remained in those pores. This simulates how dissolved mineral replaced the cells in bones, wood, etc. to create a fossil. Trace Fossils: The object created an impression in the soft material. When the material hardened, it left behind a permanent impression in the rock. This simulates how impressions left by plants, animals, and shells in mud can turn into fossils over time with the right amount of heat and pressure. Once the students have an idea of what a fossil might be and what might be preserved, then move on to the primary activity. Primary Activity (-30 minutes): Preparation - The day before this lab, it is suggested that a strip of tape is placed extending from each table (this may also be done in the gym or outside if more room is needed). Each strip of tape is divided into 5 portions as follows: o Life - Starting point o Death o Burial o Uplift o Discovery - End Point Designing the creatures (-10 minutes) o Divide the class into 6-8 groups. Each group will represent a different group of animals. Pass out the environment information card to each group (either continental environment or oceanic environment), having them fill out their thinking guide with the appropriate information from the cards. This provides students with an understanding of what environments their creatures will be living in. o Within their groups, have the students complete the thinking guide connected to the creation of their animals. It may help if the instructor completes this ahead of time to provide students with an example of answers to the questions. It may also help to provide a living example of an animal and describe the characteristics of its body to its environment. Example: Dolphin Flippers and tail-fin for swimming and navigation Sharp teeth for capturing fast-moving fish Slender body for fast movement in water (hydrodynamic) Do not have the students engage in coloring just yet as this will be utilized in the Natural Selection lesson Remind them to consider their environment and how the animal moves, eats, etc.

5 o Will it have feathers? Scales? Skin? Leather? Have the students fill out their thinking guides and begin creating their creatures on the flip side This creature will be traveling through the fossilization game to see if it will be fossilized! The Game In this game students are given chances to leave the "Life" section by landing on the "roll again" feature. As they travel on the line to fossilization and discovery, they are they are to record their journey from start to whatever point they finish in. Each group receives 2 dice and informational sheets on each section of fossilization that details what event occurs to them when they roll the dice. Starting at the beginning, Life, students roll a single dice and see what happens. Some may die and move on, some may be eaten and stay in the death section forever, some may live and have to roll again. It is all up to chance. Make sure that each student records their journey in their thinking guide This activity may prove to be a handful with regard to classroom management. If students need to be doing something because they did not move along in the fossil process, then they may begin working on the questions in their thinking guide or even sharing their experience with their peers. It would be helpful to have them stay in the place where they stopped for the final discussion. Let the students go through the activity and finish the closing questions while the students remain where they land. Closer (-5 minutes): How many people were turned into fossils? How many people were discovered by paleontologists? Can everyone become a fossil? Why didn't some animals become fossils? Remind students to finish the thinking guide as homework. Most of the questions are regarding their own journey in the life of fossils. If the questions require other information, then allow approximately 5 minutes at the beginning of Day #2 for them to finish up their activity Day #2 Opening ( minutes): Instruct students to first review their own journey to refresh their memory of the activity from the day before. After a minute of review and reflection, have the students discuss and share their journey with their tables. Next ask the students the questions from the day before: o How many people were turned into fossils? o How many people were discovered by paleontologists? o Can everyone become a fossil?

6 o Why didn't some animals become fossils? Be sure to point out that many people did not make it to the fossilization process, and even fewer people were actually extracted by scientists. So why was this? That is the motivation for the following activity. Primary Activity ( minutes): In their small groups, students are asked to construct a poster that discusses their environment, the species involved, and the outcome of the activity. Students should include the following sections: o Poster Title - This can be clever and colorful and whatever the students would like to say about their environment and species o Description of living environment - This is just a general description of the environment that was written in the species cards Description of the species involved and who played each species o The end-points - This should be a description of where each player ended their "journey." Describe HOW and WHY your species ended at the position (should be revealed on the journey's thinking guide) o Did the environment contribute to or hinder the process of fossilization? Describe. - This is a question in the thinking guide that each student may bring up and discuss with their peers. They should have already thought about this question before. What are the specific factors that helped or hindered the process of fossilization? o What parts of your body were preserved? Were there parts that were not preserved at all? Describe these parts. " What do they have in common? Think about the fossils that are on the tables for display. Are these fossils a good representation of the animal record of the past? Why or why not? Use information from your poster to give evidence for your explanation. When finished with the posters, let the students practice their presentation. Once students are finished practicing, have them place each poster around the room. As a large group, visit each poster. While at the poster, that group should explain the contents of their poster. Encourage students to ask questions about the information. o This is the chance for each group to: " Explain their environments - good or bad for fossil preservation Explain their species - hard parts versus soft parts Fossil record - terrible record of prehistoric animals as very little is actually preserved

7 Closer (-5 minutes): Come back as a class and bring all of the information back together. Remind the students of the environments more conducive to fossilization: o Marine settings - rapid burial o River settings - rapid burial o Ash falls Remind students that these processes require QUICK action for preservations, otherwise predators can pick off the remains or they will dissolve, etc. Also remind students that hard parts of an animal are the primary objects of preservations as they resist decay more readily than soft parts Finally, make sure that students remember that many animals do not get preserved in the fossil record for a number of reasons: o Environment o Soft parts (aka jelly fish and bugs) o Predation o Scavenging o Etc. Safety Guidelines Safety guidelines are relatively negligible. Care must be taken with the fossil specimens and the fossil replicas, as these are invaluable pieces donated by the Museum of Natural History and the Paleontology Repository. Consideration of Students with Special Needs Students with special needs may benefit greatly from this activity as it places learning in the context of a physical activity. It is important to discuss the statistical portion of fossil preservation while students are still standing on the fossil lines so that students with special needs may visually see what the instructor is discussing. If students require physical assistance, their peers or an aide may assist in moving across the fossil line, rolling the dice, or constructing the poster. Assessment Plan Instructional Assessments should be made during initial class discussions and the homework turned in. This should be compared to the final poster presentation. Be sure to understand if the students have developed from their initial understanding of the topic to the final understanding of the topic.