Module Overview

The module is divided into three units that encourage students to build the necessary framework to understand and answer the essential question - why do why find alligator fossils at the Gray Fossil Site, but we don't have alligators living here today. The first unit is aimed at laying the foundation for understanding what an alligator needs to survive, in terms of its preferred habitat. This unit also lays the groundwork for defining a habitat and identifying specific key parameters that can be used to define the preferred habitat for other species. Students explore an alligator's habitat needs by researching modern alligators through resources from the National Park Service, National Geographic Society, the North Carolina Zoo and other state and non-profit agencies. 

The second unit introduces students to paleontology and the fossil assemblage from the Gray Fossil Site, including alligators and five other key species. The goal of this unit is to guide students through a habitat reconstruction for the Gray Fossil Site during the early Pliocene by researching the habitat needs of the six key species recovered from the site. Students will use the same techniques employed in the first unit to identify an alligator's habitat needs, and they will use resources developed for each of the key species. The unit culminates with a habitat reconstruction for the site based on the shared needs of the six species the students have researched. The class reconstruction can then be checked against the reconstruction created by staff scientists working at the site. 

The final unit allows students to combine their knowledge from units 1 and 2 to address the module's essential questions. This is accomplished by comparing their habitat reconstructions for the modern alligator and the Pliocene-aged Gray Fossil site with a description of the modern habitat at Gray, TN. Students will use a Venn diagram to map the similarities and differences between the three habitats in order to understand why alligators no longer live in Gray TN. This understanding is expanded by then addressing the question of how animals respond to changes in their habitat through adaptation, migration or extinction. Students should have identified the key parameters of temperature, precipitation/water availability and vegetative coverage through their habitat reconstructions, and they will use these parameters to explore how the six key species from Gray would have responded to significant changes in their habitat. Students will use a Scratch simulation to set these parameters for Gray and explore how the different species would have responded. Because Scratch is an open-source coding platform aimed at children, the simulation has the added feature of allowing students to explore the code behind the simulation. After exploring the habitat changes in Gray, students should reach the conclusion that most of the species would have gone extinct because no other suitable habitat existed within migration distance; in fact, Pliocene-aged Gray had a non-analogue habitat that does not exist in today's world. To substantiate this conclusion, students will learn about the current understand of longer-term environmental changes at Gray during the early and middle Pliocene that would have impacted the species they have studied. Finally, students will demonstrate their understanding of the topics covered in this module and the overall driving question by writing a fictional letter from the Gray alligator to the surviving Slider Turtle explaining why and where they moved and what they like about their new home. 

Module Outline & Standards

Module Essential QuestionWhy have scientists found alligator bones in a fossil site in NE Tennessee when they don’t live there today?

Unit 1. Essential Question: Where do alligators live today and what makes them happy?

  • Lesson 1: Where do alligators live in the wild today?

    1. Introduction. Introduce students to the driving question. Ask students to share any prior knowledge they have about alligators and where they live. Class prior knowledge should be recorded on the class jamboard, and students should take a few minutes to draw a picture in their science journal of what they think an alligator's habitat looks like.

    2. Direct Observations. Students should watch the embedded youtube videos to observe alligators in their preferred habitat. Each student should share one observation they made about the alligator's habitat and one question they had about the alligator and its habitat.

    3. Classroom definition. Students should read the brief definition of a habitat and then brainstorm as a class to come up with their own definition, including at least three things an animal needs to survive (e.g., food, water, shelter). This defintion and the parameters should be recorded on the class jamboard.

    Resources: Project jamboard (virtual whiteboard available through google); student science journals; Youtube videos (NC zoo, National Park Animals for Kids)

    Performance Expectations: Building towards 

      3-LS4-1. Analyze and interpret data from fossils to provide evidence of the organisms and the environments in which they lived long ago.

      3-LS4-3.Construct an argument with evidence that in a particular habitat some organisms can survive well, some survive less well, and some cannot survive at all.

  • Lesson 2: What makes alligators happy?

    1. Review. Review what students learned/observed from their habitat research. Propose the question: What is an alligator's habitat? Have students brainstorm the types of information they need know about alligators in order to reconstruct their habitat. For instance, what do alligators eat, how do they interact with each other, where do they build nests, do they have predators or competitors, where are alligators found and are there temperature or precipitation limits to the modern alligator range?

    2. Research. Students should visit various websites to find information about the modern alligator's habitat. Students can work alone or in small groups to fill out the alligator habitat worksheet provided on the lesson page. For younger students, small groups could be assigned one or two requirements to research, such as food or water. Older students can work alone or in groups to fill out the entire worksheet. .

    3. Classroom definition. Students should share their findings for each of the requirements on the worksheet, and the class should synthesize this information into a working definition of an alligator's preferred habitat. Students should then revisit their original ideas from Lesson 1 about an alligator's habitat needs. They should also revisit their science journal drawings of an alligator's habitat and think about whether their research has changed their ideas about that habitat.

    Resources: Project jamboard (virtual whiteboard available through google); external websites (NC zoo, National Geographic for Kids, LA Department of Wildlife and Fisheries) and Youtube videos (WGCU Curious Kids)

    Performance Expectations: Building towards 

      3-LS4-1. Analyze and interpret data from fossils to provide evidence of the organisms and the environments in which they lived long ago.

      3-LS4-3.Construct an argument with evidence that in a particular habitat some organisms can survive well, some survive less well, and some cannot survive at all.

Unit 2. Essential Question: What animals are found in the fossil assemblage at Gray, and what made them happy?

  • Lesson 1: What types of fossil animals are found at the Gray Fossil Site?

    1. Intro to Paleontology. Students are introduced to the science of paleontology. 

    2. Intro to the Gray Fossil Site. Students learn about the Gray Fossil Site in Gray, TN, including how old it is, how it formed, how it was discovered and what types of animals have been recovered from the fossil record.

    3. Classroom definition. Students should share their findings for each of the requirements on the worksheet, and the class should synthesize this information into a working definition of an alligator's preferred habitat. Students should then revisit their original ideas from Lesson 1 about an alligator's habitat needs. They should also revisit their science journal drawings of an alligator's habitat and think about whether their research has changed their ideas about that habitat.

    Resources: This is a text-heavy introduction to both Paleontology and the Gray Fossil Site; no outside resources are needed. 

    Performance Expectations: Building towards 

      3-LS4-1. Analyze and interpret data from fossils to provide evidence of the organisms and the environments in which they lived long ago.

      3-LS4-3.Construct an argument with evidence that in a particular habitat some organisms can survive well, some survive less well, and some cannot survive at all.

  • Lesson 2: What do scientists think made those animals happy?

    1. Review. Students will begin by reviewing their class definition of an alligator's habitat, before reading the included text outlining the habitat needs of the Pliocene-aged alligators from the Gray Fossil Site. They should compare the information recorded on their habitat worksheet from Unit 1 with the information provided in this lesson. There will be no substantial differences in the information. 

    2. Research. Students should once again split into small groups, or work independently (depending on age), and research the habitat needs of five key species recovered from the fossil record at Gray, TN. Depending on class size, groups can be assigned a single species to research, or they can be tasked with researching all five species. Information should be recorded on the habitat requirement worksheet available on each species information page. 

    Resources: Information pages and videos for each species, habitat requirement worksheets

    Performance Expectations: 3-LS4-

  • Lesson 3: What does the fossil assemblage tell us about the paleoenvironment at the Gray Fossil Site?

    1. Data Sharing. Students should share the information from their species' habitat requirement worksheets with the class and record the information on the provided worksheet or the project jamboard.

    2. Data Synthesis. Once all of the information is tabulated to show the requirements for each species, students should  try to identify similarities in habitat needs. These needs should be synthesized to create a paleo environmental reconstruction of the fossil site during the early Pliocene. 

    3. Evaluation. Once the class is happy with their reconstruction, they should check it against the official reconstruction developed by staff scientists. Students should click the tab at the bottom of the page to reveal an illustration and a text explanation of this reconstruction. Students should then discuss how similar their class reconstruction was to the official reconstruction, and evaluate any major differences. Students should have a good understanding of this reconstruction before moving on to the final unit.

    Resources: Jamboard or Paleohabitat Reconstruction worksheet

    Performance Expectations:Building towards 

      3-LS4-1. Analyze and interpret data from fossils to provide evidence of the organisms and the environments in which they lived long ago.

      3-LS4-3.Construct an argument with evidence that in a particular habitat some organisms can survive well, some survive less well, and some cannot survive at all.

Unit 3. Essential Question: Why did alligators live at the Gray Fossil Site in the Pliocene, but they don’t live there today??

  • Lesson 1: How does our research on past and modern habitats help us understand why alligators no longer live in Gray TN? 

    1. Research. Students should read the information provided in the lesson about the modern habitat in Gray, TN. While reading though this information, they should keep in mind their class reconstruction of the paleo environment for this area during the early Pliocene.  

    2. Habitat Comparison. Students should create a Venn Diagram to compare the modern Gray habitat, the ancient Gray habitat and the modern alligator habitat. They should look for similarities and differences between these three environments, with the goal of understanding how this comparison can help them answer the module's driving research question.   

    3. Discussion. Students should discuss their findings from the Venn Diagram comparison and how they think it helps them to answer the driving reserach question.

    Resources: Venn Diagram worksheet (provided), Jamboard, or science journals

    Performance Expectations

      3-LS4-4. Make a claim about the merit of a solution to a problem caused when the environment changes and the types of plants and animals that live there may change

  • Lesson 2: How would the six animals we studied have responded to changes in their habitat at Gray?

    1. Review. Students should review the information provided about the different response methods that species employ to navigate habitat changes.  

    2.  Modeling. Students should refer to the class jamboard or tabulation worksheet from the end of Unit 2 to review the habitat requirements for the six species they studied from the Gray Fossil site. Working individually or in small groups, they should think predict how they think the species would respond to a specific change in their habitat, such as temperature, precipitation or coverage, and then they should check this prediction by running the simulation in the Scratch program. Students should keep track of how their predictions compared to the modeled simulations. 

    3. Discussion. Students should share their findings and discuss how well their predictions matched the outcomes of the simulations. They should also discuss whether they noticed any patterns in the way the different species responded to changes in their habitat. 

    Resources: Jamboard or tabulated worksheet from Unit 2 Lesson 3; Scratch program

    Performance Expectations

      3-LS4-3.Construct an argument with evidence that in a particular habitat some organisms can survive well, some survive less well, and some cannot survive at all.

      3-LS4-4. Make a claim about the merit of a solution to a problem caused when the environment changes and the types of plants and animals that live there may change

  • Lesson 3: How did the habitat at the Gray Fossil Site change over the course of the Pliocene?

    1. Review. Students should review the information provided on the lesson page that outlines the current reconstruction of habitat changes at the Gray Fossil Site over the course of the early and middle Pliocene, and how scientists believe the six researched species responded to those changes. 

    2. Classroom Discussion. Students should review their class hypotheses from Lesson 1 about how the changes in habitat between the Pliocene and today can explain why we no longer find alligators in Gray, TN. 

    Resources: Venn diagram, Jamboard or science journals from Unit 3 Lesson 1.

    Performance Expectations

      3-LS4-1. Analyze and interpret data from fossils to provide evidence of the organisms and the environments in which they lived long ago.

      3-LS4-3.Construct an argument with evidence that in a particular habitat some organisms can survive well, some survive less well, and some cannot survive at all.

      3-LS4-4. Make a claim about the merit of a solution to a problem caused when the environment changes and the types of plants and animals that live there may change

  • Lesson 4: Wrap Up and evaluation - pulling it all together

    1. Evaluation. Students should read the example "slider turtle" letter provided on the lesson page and then write their own response letter from the alligator's point of view. This letter should explain why the alligator left Gray and describe what the new habitat looks like.

    Resources: Science journal, Google doc, or similar writing program. 

    Performance Expectations

      3-LS4-1. Analyze and interpret data from fossils to provide evidence of the organisms and the environments in which they lived long ago.

      3-LS4-3.Construct an argument with evidence that in a particular habitat some organisms can survive well, some survive less well, and some cannot survive at all.

      3-LS4-4. Make a claim about the merit of a solution to a problem caused when the environment changes and the types of plants and animals that live there may change

Project Team

Project Team info/bios go here

Funding Acknowledgement

Funding Acknowledgement goes here - Nat Geo verbage