Fossils Document Changes To Ecosystems
Lesson 7 of 12
Objective: SWBAT use fossil evidence as support to describe changes to the ecosystem of a particular region of the US.
Not long ago I was having a conversation with a colleague about some rock core samples that contained fossil evidence of how Illinois used to be underwater. This conversation reminded me that we get so caught up in "what is" that we forget to ever consider "what was". This unit on common ancestry and fossils is the perfect time to have students explore the geological history of their region and practice SP7, argumentation based on evidence, as students use fossil evidence to support claims about the changes to ecosystems of different states, as well as SP8 as students gather and communicate information.
The purpose of this warm-up activity is twofold: first to introduce students to the idea that the ecosystem that students are surrounded by every day was not always as it is now. Second, it models for the students how to use fossils as evidence to support claims regarding prehistoric ecosystems which is what the students will be tasked with in the activity.
In researching to prepare this lesson I found two great resources for my area. The Illinois State Museum has an exhibit based on the fossil finds that clearly shows how this region used to be covered by a shallow, tropical sea. Additionally, Virtual Silurian Reef has a lot of information about this time period and may be especially relevant for Illinois and Wisconsin teachers. With the help of your area's universities, educational organizations such as museums, zoos and aquariums, the National Park Service, and the U.S. Geological Survey there are many resources that would allow you to adapt this lesson to your region.
Using the PowerPoint Illinois Ecosystem, I have students brainstorm together descriptions of the current ecosystem of Illinois to activate their prior knowledge. The PowerPoint goes on to describe some of the ancient animals found in the under water ecosystem that was present 400 billion years ago in Illinois. As I go over those animal fossils, I model how a fossil can be used as evidence (proof) that IL was an aquatic ecosystem. This requires some research on the specific organisms depicted in the fossils and I explain how I gathered this information to the students since they will be doing the same type of activity. Here is a quick video that explains how I use this resource during class.
Students may have trouble imagining how these fossil finds are beneficial. This short video describes another ancient ecosystem of IL and this find might benefit current research on global warming.
This activity involves students researching a fossil rich area of the United States to determine if the current ecosystem existed during prehistoric times. Students will use relevant fossil finds as evidence as they document their conclusions and compare the current ecosystem with the ancient ecosystem.
As I was researching materials for this lesson, I came across this interactive map that allows one to view dinosaurs and other prehistoric animals by state, it is pretty awesome! This map really allows for students to determine which state they would like to research; however, to ensure students are able to find enough information on fossil finds I am choosing to limit the options to the states named in the CNN article 8 Places For Fantastic Fossil Finds. I have students working at 8 lab tables so each table will focus on one of the states mentioned in the article:
- New Mexico
By focusing on these locations that are noted for their "fantastic fossil finds", students can compare the sites and determine why these areas have a rich collection of fossils as opposed to other locations within the US should you choose to incorporate that idea.
Students have two to three days to complete this activity. I envision students using one day to find out about the current ecosystem, one day to find out about the ancient ecosystem, and one day to build the presentation. However, I always allow students to determine how to "tackle" a project like this and it is quite likely that many groups will choose a "divide and conquer" strategy in which part of the group will focus on present day, one part will focus on prehistoric, and they use Google Presentation to create the visual aid/organize information simultaneously. I do not micromanage how students choose to complete the task as long as they complete the requirements by the due date.
Students present their completed project to the class.
Prior to allowing students to begin their research, I show them the following video that discusses 15 fantastic fossil finds.
Following the video I point out that it takes a lot of research for scientists to determine all of this information. As the students conduct research and find plant and animal fossils found in the state they are researching, they can gain more information about that ecosystem by researching what we know about those animals (similar to what I did with the warm-up PowerPoint).
Students are not always used to conducting this type of "multilevel" research and it helps to point out that to get enough information on a prehistoric ecosystem this might be necessary. I recommend giving students time to get started and then conducting a mini-lesson that describes what specifically you hope to see with their presentations. The following video explains in a bit more detail how I accomplished this and the Fossils Document Changes To Ecosystems Rubric is what I used to assess the project. The Student Example - Montana is one of my favorite examples as it shows how students used the notes portion of the slide to keep track of the important information they wanted to discuss during the presentation.
At the conclusion of the presentations students participate in a "whip around". This is a quick way to have students share one thing they learned from the presentations.
I have all of the students stand. I toss a ball to a student and they share one thing they learned during the presentations. This student tosses the ball to another students then sits. The person with the ball shares what they learned but they cannot repeat what the prior student shared. This process continues until all students have shared something.
Note: I usually toss the ball to one of the students who may struggle to come up with an answer further into the activity to ensure success. Also, you may choose to adapt the whip around to include questions as well as things learned.