Megan Hendrickson | Science Educator | Academy of the Holy Names, Tampa FL
Victor Perez | Geology PhD student | University of Florida
- How could scientists determine the length of Megalodon using fossil teeth?
- How do scientists use modern sharks to help them gain understanding of fossil sharks?
6th Grade Earth History
7th Grade Populations and Ecosystems
Note: we made a nice lesson variation between 6th and 7th grade. In 7th we focused on megalodon’s position as an apex predator and in 6th we focused on how scientists learn from fossils.
85 Minute Block
2- 45 minute class periods
NGSS Performance Standards
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.
MS-LS2-1 Analyze and interpret data to provide evidence for the effects of resource availability on organisms and populations of organisms in an ecosystem.
MS-LS2-4 Construct an argument supported by empirical evidence that changes to physical or biological components of an ecosystem affect populations.
MS-LS1-5 Construct a scientific explanation based on evidence for how environmental and genetic factors influence the growth of organisms.
NGSS Disciplinary Core Ideas
LS2.A: Interdependent Relationships in Ecosystems
- In any ecosystem, organisms and populations with similar requirements for food, water, oxygen, or other resources may compete with each other for limited resources, access to which consequently constrains their growth and reproduction. (MS-LS2- 1)
- Growth of organisms and population increases are limited by access to resources. (MS-LS2-1)
LS2.C: Ecosystem Dynamics, Functioning, and Resilience
- Ecosystems are dynamic in nature; their characteristics can vary over time. Disruptions to any physical or biological component of an ecosystem can lead to shifts in all its populations. (MS-LS2-4)
Common Core State Standards Connections
6.EE.C.9 Use variables to represent two quantities in a real-world problem that change in relationship to one another; write an equation to express one quantity, thought of as the dependent variable, in terms of the other quantity, thought of as the independent variable. Analyze the relationship between the dependent and independent variables using graphs and tables, and relate these to the equation. (MS-LS1-6),(MS-LS2-3)
MP.4 Model with mathematics. (MS-LS2-5)
Cross Cutting Concepts
Patterns can be used to identify cause and affect relationships. (MS-LS2-2)
Stability and Change
Small changes in one part of a system might cause large changes in another part. (MS-LS2-5)
Cause and Effect
Cause and effect relationships may be used to predict phenomena in natural systems. (MS- LS3-2)
Science and Engineering Practices
Developing and Using Models
Modeling in 6–8 builds on K–5 experiences and progresses to developing, using, and revising models to describe, test, and predict more abstract phenomena and design systems.
- Develop and use a model to describe phenomena. (MS- LS3-1),(MS-LS3-2)
Connections to Engineering, Technology, and Applications of Science
Interdependence of Science, Engineering, and Technology
Engineering advances have led to important discoveries in virtually every field of science, and scientific discoveries have led to the development of entire industries and engineered systems. (MS-LS4-5)
Resources and Materials
- Megalodon Student Handout and data collection sheet
- Megalodon PowerPoint
- Student Interactive Notebooks
- 2D (upper | lower) — or — 3D Megalodon teeth
- For size accuracy, do not resize images. The images provided are life-size and high resolution (300dpi).
- iPads or Laptops (optional)
- Calculators (optional)
Key Academic and/or Scientific Language
Fossil, paleontology, algorithm, crown height, lateral, anterior, posterior, root, neonate, juvenile, adult, lingual, labial, serrations, bourlette
What knowledge and skills will students acquire?
Student will be able to:
- Use an interactive notebook
- Collaborate with peers during discussions
- Take measurements in millimeters
- Convert between units
- Ask questions about the scientific process when determining Megalodon total length
- Understand relationships between modern and fossil sharks
- Identify basic parts of a Megalodon tooth
- Solve a linear equation
- Identify and discuss variables that cause discrepancies in total length calculations
- Student handouts will be assessed for completeness and math computation
- Student reflections on data analysis will show understanding of variables that cause differences in total length calculations
- Questions about the activity and outcomes will be included on unit assessment
How big was Megalodon?
Driving Question: How do scientists determine total length of Megalodon sharks using only fossil shark teeth?
- Science Starter (to be completed in students’ interactive notebook): What is a fossil? What does a fossil tell scientists about the past?
- Distribute student activity worksheets
- Share Power Point presentation “How Big Was Megalodon?” Refer to the notes on each slide of the power point to guide you through the process of determining Megalodon Total Length.
- Once a basic introduction of Megalodon and the activity have taken place distribute the 2D or 3D teeth (If working in groups you may choose to give both a 2D and 3D tooth for the students to work with. This will facilitate a discussion about experiences with 3D vs. 2D model.) Give students a couple of minutes to look at their tooth.
- Copy the student data chart onto a white board or smart board. Have one student from each group share their data on the class chart.
- Analyze the class data and determine what could have caused different total length calculations. Students should be able to determine that crown height and tooth location in the jaw produced the differences in the total length.
Megalodon is a perfect specimen to introduce concepts of geometry in a science class. Download the following materials:
- Nyberg KG, Ciampaglio CN, Wray GA (2006) Tracing the ancestry of the Great White Shark, Carcharodon carcharias, using morphometric analyses of fossil teeth. J Vertebrate Paleontology 26: 806-814.
- Pimiento C, Ehret DJ, MacFadden BJ, Hubbell G (2010) Ancient nursery area for the extinct giant shark Megalodon from the Miocene of Panama. Plos One, 5(5):e10552.
- Shimada K (2003) The relationship between the tooth size and total body length in the white shark, Carcharodon carcharias (Lamniformes: Lamnidae). J Fossil Res 35: 28-33.
- Gottfried MD, Compagno IJV, Bowman SC (1996) Size and skeletal anatomy of the giant megatooth shark Carcharodon megalodon. In Klimley Ap, Ainley DG, eds. Great white sharks: the biology of Carcharodon carcharias. San Diego: Academic Press. pp 55-89.