To introduce students to how the scientific enterprise, science, and technology were used in discovering and understanding dinosaur eggs found during a famous paleontological expedition in Argentina.
This lesson makes use of a book by the same name, Dinosaur Eggs Discovered! Unscrambling the Clues, written by Lowell Dingus, Luis M. Chaippe, and Rodolfo Coria. This book is one of the winners of the 2008 SB&F Prize for Excellence in Science Books (you can read about this prize at: Book Award). SB&F, Science Books & Films, is a project of the American Association for the Advancement of Science.
The book summarizes 1997 and 1999 expeditions to a spectacular fossil-collecting site in Patagonia where the authors discovered hundreds of eggs laid by 40-foot-long titanosaur dinosaurs on a floodplain of the Late Cretaceous age.
The book traces the steps of the scientists through one of the richest dinosaur discoveries in recent history. Rather than depicting the discovery as a result of formalized steps of the scientific method, the authors describe the creative and challenging ways in which they investigated questions. Student conception of science is often that of a laboratory setting in which scientists begin with observations and end with conclusions. While the scientific method might be familiar to students as a model for finding answers about the natural world, scientists rarely carry out experiments in such a recipe-like manner. Missing in descriptions of the scientific method are the critical thinking, imagination, and creative problem-solving techniques that scientists depend upon. The three authors of this book describe how they found dinosaur eggs unexpectedly and the challenges they faced in trying to answer questions about their find. Each chapter begins with a question they asked and recounts the scientific thinking, tools, and imagination that were utilized to best answer the question.
It is helpful for students to have some background in geology and the structure of the earth. Specifically, it is helpful to review the rock cycle, the geologic time line, and how the earth has changed over time. Alternatively, this lesson can serve as an excellent multidisciplinary introduction to geology, paleontology, and biology. This lesson is aimed towards the middle-school age group. Thus, while the reading may be technical at times, it is best to focus on the main ideas—discovery, the scientific enterprise, evidence collection, and the tentative nature of scientific answers.
Before beginning this lesson, it is also recommended to review the definition of a fossil and to describe how fossils are formed over time. It is also helpful to address misconceptions about dinosaurs and to clarify the definition of a dinosaur. Students may think dinosaurs include any extinct animal discovered by paleontologists or animals whose scientific name includes “saurus.” Clarify the difference between dinosaurs and other ancient animals, such as swimming reptiles or ancient birds. Also clarify that dinosaurs lived during the Mesozoic Era only; ancient animals from the current Cenozoic Era are not classified as dinosaurs. On pages 32 – 33 of the book, the authors provide a description and classification of dinosaur groups. It may be helpful to review these two pages with students to clarify their understanding of dinosaurs and, specifically, sauropods.
Please read the book before teaching this lesson for background information about the expeditions, the discovered dinosaur eggs, titanosaurs, and dinosaur evolution, in general.
Before the lesson, cut out the individual dinosaur bones from each Fossil Sheet and place them in an envelope. The bones do not have to be cut out around the lines. It is helpful to number each envelope and all the bones with a single digit so that bones of different envelopes do not eventually get mixed up. Another helpful way to organize the bones is to copy the fossil sheet on different colors so that the bones can be easily sorted apart in the event of mix-up.
To begin, engage students in the lesson by having them do the Great Fossil Find activity, which is an engaging introduction to the book and reinforces the general idea that science is based on evidence, uncertainty, and creativity. In the Great Fossil Find, students conduct a mock paleontological expedition. Students “discover” fossilized bones of a dinosaur and work in teams to construct a partial skeleton. The bones are discovered a few at a time, challenging students to think creatively and to consider multiple ways of putting the pieces together. Students also utilize a reference material containing complete drawings of known skeletons to help them fill in parts to their partial dinosaur skeleton.
Before beginning the activity, ask students:
- How is it possible for scientists to study things that happened millions of years ago?
- (Science is based on the collection of evidence. Scientists collect this evidence and use reasoning to determine what this evidence tells us about the world. Students will likely mention fossilized bones, but encourage students to think of other evidence from the past such as volcanic ash, age of rocks, and fossilized plant material.)
- What does a paleontologist do?
- (A paleontologist is a scientist who studies fossils of ancient living organisms.)
- What types of animals do paleontologists study?
- (Students will likely mention dinosaurs, but emphasize that they also study other ancient life-forms such as fish and birds.)
Emphasize that paleontologists use a collection of evidence, such as those mentioned in the first question, to understand how living organisms lived millions of years ago and what they looked like.
For the activity, students should work in small groups (maximum of four) that represent paleontological teams. The teams are digging in the same area but at different sites. Read the Great Fossil Find narrative to students to guide them through the discovery process of finding bones. Although the narrative asks students to withdraw four bones from the envelope, previous teacher experience with this activity suggests that three, two, or even one bone can be removed at a time. To make it more realistic, different teams can be told to withdraw different numbers of bones. At step D of the narrative, student groups should walk around and examine the bones discovered by other teams. Each group should then use this information to make any adjustments to the skeleton they have constructed with their discovered bones. At step E, provide each group with a Skeletal Resource Manual and have them determine what their fossil discovery most closely resembles. Step F asks students to fill out a worksheet; it is to the teacher’s discretion to use with students.
After the activity, ask students these questions. Answers will vary.
- What was challenging about this activity for you and your group?
- What assumptions did you and your team members have about the animal when you started?
- How did the discovery of new bones challenge your group?
- What information did your team get from other groups? How did new information change your interpretation?
- How did the information in the skeletal resource guide help your team?
- Why is this activity a good example of actually doing science?
- What can you say about where and how this animal lived?
In this section of the lesson, students will work in teams to answer some of the questions posed in the book. Before they engage in their research, have students listen to a podcast interview with Dinosaur Eggs Discovered: Unscrambling the Clues author Lowell Dingus. Once they've listened to this podcast, you could lead them in a class discussion using questions like these:
- What happened on the second day of the expedition? (The scientists came upon an unexpected discovery of dinosaur eggs.)
- How did the scientists work together as a team to get a complete picture of the discovery? (The fossils usually raise a lot of interesting questions about the animals, environment, age of rocks, etc. Paleontology can be approached from different perspectives, either biological or geological. It takes a whole host of specialists to paint a picture of the animals and the environment.)
- What role do museums play in paleontological research? (Museums have behind the scenes a vast library of specimens. This library is very important because it is the body of data from which the scientists' research is devised.)
- What questions are still unanswered? (Some questions that are still unanswered include the color of the living animals, what kinds of calls they might have made, etc. There are lots of questions that remain mysteries.)
- What was it like for the authors to write the book? (Lowell Dingus had written a lot of museum labels that went along with the specimens in the museum. This experience gave him a better understanding of what people might be looking for when reading the book. He and the other authors set up the book with questions that represented mysteries that once they had found the dinosaur eggs they had to try to solve. This approach relfects the way that they conduct research.)
Before students go on to read the book, you can suggest that they first look at the SB&F Book Club Guide: Dinosaur Eggs Discovered!. This guide provides information on what the book is about, the author, reasons why they should read it, and questions to think about as they read it. You can either direct students to go to the guide online or you can provide them with print-outs of the two-page guide.
Now have students read Chapter One: An Unexpected Discovery of Dinosaur Eggs Discovered! Unscrambling the Clues. Students can use the An Unexpected Discovery student sheet to record their answers. You can find answers to the questions on the An Unexpected Discovery teacher sheet. Discuss the questions in class. During discussion, show students a map of Argentina, pointing out the area of Patagonia, and pass around samples of sandstone and mudstone.
Tell students that they will work in teams to answer some of the questions posed by both students and the scientists. Each team will read a chapter of the book and use online resources to answer their particular question. The teams will then present their findings to one another. Tell students that the goal is to develop a deeper understanding of how science is actually carried out and done in the field. There are many questions that arise and scientists have to rely on their creativity, observations, technology, and each other to find the answers. Remind students of their experiences with the Great Fossil Find activity; although scientists may not always be 100% sure of their answer, the scientific process allows them to determine the closest, most plausible answer.
Have students work in eight teams and assign each team one chapter from Chapters 2 – 9. To organize the teams, you may want to write the eight questions on a board and have students pick which one they would like to investigate. Provide each team with the Dinosaur Eggs Discovered student sheet to help guide their reading and presentation. The Dinosaur Eggs Discovered teacher sheet provides answers.
Have students read the final chapter of the book: Auca Mahuevo’s Unique View of the Past (Chapter 10). After the reading, ask students to refer back to their table of observations and notes from the student sheet. Ask them these questions:
- With such little information that was initially known about the dinosaur eggs, how is it possible for scientists to construct the past of Auca Mahuevo?
- (Students should refer to what the evidence tells scientists about the past. For example, the mudstone and sandstone indicated flowing water, analysis of the rocks indicated the age, embryo bones and skins indicated the type of dinosaur that laid the eggs, the presence of fossils of other dinosaurs indicated the type of predators that were present.)
- How has this fossil find added to what we know about dinosaurs?
- (Scientists now know what sauropods looked like when they first hatched, that they laid eggs, and had well-developed nests. Because of the presence of multiple nests, scientists also know that the nests were part of a massive nesting colony frequented by at least hundreds of sauropod mothers at one time.)
- Do you think that luck has a role to play in discoveries?
- (Answers will vary but students should bring up that the scientists did not expect to find dinosaur eggs. Also, the site was previously undiscovered and they happened to come across it while looking for other types of fossils.)
- How were the scientists creative in answering their questions?
- (The team had to think of different possible answers to their questions and then seek evidence for those proposed answers.)
- Why was teamwork important in this expedition?
- (The scientists did not rely completely on themselves. They were dependent upon the locals and dozens of geologists and paleontologists to understand what they had found and to determine the answers to their questions.)
- What other questions do you have about the dinosaurs at Auca Mahuevo?
- (Answers will vary.)
Students can continue a study of dinosaurs with Hollywood Dinosaurs. This lesson asks students to use evidence and reasoning to construct theories of dinosaur behavior.
In a number of places in the book, the authors highlight special subjects that can be further researched by students in groups and presented as follow-up. In addition, these subject areas tie different areas of science and the role that science plays in society. These special subjects include: Dating Rocks (p. 25), Summer Sledding in the Desert (p. 30), Lab Gear (p. 41), Photographers in the Field (p. 65), and Fossil Poaching (p. 101).