Fossil Journal. Nature in the Classroom. Slater Museum of Natural History University of Puget Sound Tacoma, Washington

Transcription

1 Fossil Journal Nature in the Classroom Slater Museum of Natural History University of Puget Sound Tacoma, Washington Name: School: Grade: Start date: End date:

2 Table of Contents Page 4 Fossilization Diagram Page 7 Leaf Anatomy Page 10 Plant Communities Data Table Page 14 Extant and Extinct Leaves Data Tables Page 17 Glossary This curriculum and journal were authored by Robert Niese, Sal Greenberger, Mary Krauszer, Brenda Miller, and Slater Museum of Natural History staff. The Slater Museum of Natural History s goals are to preserve and provide a collection of specimens to be used for research, education and inspiration. The museum houses one of the largest collections of Pacific Northwest bird, mammal, reptile, amphibian and plant specimens. We appreciate the support of the Institute of Museum and Library Services, Mortensen Family Foundation, and Wells Fargo Foundation in the development of these materials. 2

3 Lesson 4: Reading the Fossil Record Goal Students will learn how paleontologists can use observations about present-day Earth to better understand the past. As a class, answer the following questions: How old is the Earth? What three things make a fossil?

4 Lesson 4: Leaves of Change Reading the Fossil Record Fossilization Diagram Fossilization Process What is one of the most common ways that fossils are formed? Image by and courtesy of Becky Barnes, paleontologist North Dakota Geological Survey Step 1. A living organism dies (such as this dinosaur) and the soft parts start to decay. Hard parts like bones and teeth are left behind. Step 2. The remains of the dinosaur are quickly but gently buried by mud (sediment) and water. Step 3. More layers of sediment cover the remains, hardening and pressing down on the forming fossil. Over time, minerals seep into the remains and slowly turn them into rock. Step 4. After at least 10,000 years, erosion wears away the top rock layers and exposes the fossil for people to find! Types of Fossils 4

5 Lesson 4: Leaves of Change Reading the Fossil Record Fossil Identification Fossil Identification Activity Working with your group, study each of the six fossils below. For each fossil, circle the type of fossil you think it is, and write a prediction for what organism you think that fossil is. Fossil A a. Body Fossil b. Trace Fossil c. Cast/Mold Fossil What organism do you think this fossil is? Fossil D a. Body Fossil b. Trace Fossil c. Cast/Mold Fossil What organism do you think this fossil is? Fossil B a. Body Fossil b. Trace Fossil c. Cast/Mold Fossil What organism do you think this fossil is? Fossil E a. Body Fossil b. Trace Fossil c. Cast/Mold Fossil What organism do you think this fossil is? Fossil C a. Body Fossil b. Trace Fossil c. Cast/Mold Fossil What organism do you think this fossil is? Fossil F a. Body Fossil b. Trace Fossil c. Cast/Mold Fossil What organism do you think this fossil is? 5

6 Place your leaf here to create a leaf rubbing on page 8. 6

7 Lesson 4: Leaves of Change Reading the Fossil Record Leaf Margins Diagram Leaf Anatomy margin vein simple leaf compound leaf leaflet Leaf Margins Entire (Untoothed) Serrate (Toothed) 7

8 Where I found my leaf: When I found my leaf: Leaf Rubbing: Place your leaf on page 6 to create a rubbing here. 8

9 Lesson 4: Leaves of Change Reading the Fossil Record Leaf Scientific Sketch Sketch the leaf you brought in to class in the space provided, and write the type of margintoothed or untoothed- you think your leaf has. Make sure to draw accurate margins, vein patterns, and shape, and fill the whole box with your sketch. What is always included in a scientific sketch? Margin Type: 9

10 Lesson 4: Leaves of Change Reading the Fossil Record Plant Communities: Data Collection Plant Communities around the World Write the location of your Plant Community. Using what you have learned about leaf morphology, determine if each plant has a toothed or untoothed margin, then record the number of toothed and untoothed plants below. Collecting data from your Plant Community My Plant Community: # Plants with Untoothed Margins: # Plants with Toothed Margins: # Total Plants: Calculating the Fraction of Untoothed Leaves # Plants with Untoothed Margins # Total Plants Fraction of Untoothed Leaves Finding the Mean Annual Temperature of your Plant Community Look at the map on the other side of your laminate to find the M.A.T. of your Plant Community. The Mean Annual Temperature in my Plant Community is. Compiling our Data As each group shares the data they ve collected for their Plant Community, fill out the table below. Pay close attention for any patterns or trends in the data! # Untoothed Plants # Toothed Plants Alaska Vermont Kentucky Argentina Tanzania Sudan # Total Plants Fraction of Untoothed Plants M.A.T. ( C) 10

11 Lesson 4: Leaves of Change Reading the fossil record Graphing the Fraction of Untoothed Leaves and M.A.T. Find the point where your Mean Annual Temperature (x-axis) and Fraction of Untoothed Leaves (y-axis) line up on the graph, and make a dot. Do this for all Plant Communities, and draw a line connecting the points. 1 Fraction of Untoothed Leaves 8/9 4/5 5/7 3/5 1/2 2/5 2/7 1/ Mean Annual Temperature ( C) What is the trend you see on the graph? What does this show about the relationship between MAT and the Fraction of Untoothed Leaves? For example, in a place with a high MAT would you see many or few Untoothed leaves? 11

12 Lesson 4: Leaves of Change Reading the fossil record Extant Leaves: Data Collection Making a Hypothesis about the Past I think Washington was (circle one): warmer or colder 110 million years ago. According to your hypothesis, what would leaf margins in Washington be like 110 million years ago? Be sure to explain your reasoning! Extant Washington Leaf Community Note what color box your group has. Using what you have learned about leaf morphology, place each leaf into the correct category based on its margins (Toothed or Untoothed). Check the box that describes the margin of each leaf. My Group Color: Leaf ID # Toothed Margin Untoothed Margin 12

13 Lesson 4: Leaves of Change Reading the fossil record Extinct Leaves: Data Collection Pick one extinct leaf fossil and sketch it in the space below. Make sure to include all the parts of a scientific sketch, and to fill the entire box with your sketch. Leaf # Margin Type: Note what color box your group has. Using what you have learned about leaf morphology, place each leaf fossil into the correct category based on its margins (Toothed or Untoothed). Check the box that describes the margin of each leaf fossil. My Group Color: Leaf # Toothed Margins Untoothed Margins 13

14 Lesson 4: Leaves of Change Reading the fossil record Compiling Extant and Extinct Leaf Data As each group shares their data, fill out the tables below and calculate the Fraction of Untoothed Leaves for both extant and extinct leaves. 14

15 Lesson 4: Leaves of Change Reading the fossil record Calculating the M.A.T. Graph your Fraction of Untoothed Leaves(on the y-axis) to find the Mean Annual Temperature (x-axis). Do this twice once for your fossil leaves and once for your extant leaves. 1 Fraction of Untoothed Leaves 8/9 12/15 4/5 5/7 9/15 3/5 1/2 6/15 2/5 2/7 5/15 3/15 1/ Mean Annual Temperature ( C) Fraction of Untoothed Leaves for extant plant communities: MAT of Washington today: C Fraction of Untoothed Leaves for extinct plant communities: MAT of Washington 110 million years ago: C 15

16 Lesson 4: Leaves of Change Reading the fossil record Conclusion Now that you have found the MAT for present-day Washington (extant leaves) and Cretaceous Washington (extinct leaves), was our state warmer or colder 110 million years ago? Explain how you figured this out- make sure to include a summary of the trend you found between the Fraction of Untoothed Leaves and the MAT. 16

17 Glossary - adaptation a trait, or characteristic of a trait, which improves an organism s ability to survive and reproduce in its environment - climate the typical weather conditions of a region; includes temperature, air pressure, humidity, rainfall, sunshine, cloudiness, and winds, throughout the year, averaged over many years - community (in biology) a group of many species of organisms that interact in an area - ecosystem a community of organisms and their physical habitats - entire (in reference to margins) smooth edged, without teeth - extant still in existence - extinct no longer in existence - fossil the remains or impression of a prehistoric organism preserved in rock - leaf margin the edges of a leaf - MAT acronym for mean annual temperature ; the average of all temperatures for a given region in a year - mean (in math) the average; the sum of all quantities divided by the number of quantities - paleontology the study of ancient existence - serrate (in reference to margins) toothed, jagged 17