Extinction Events

Author: Jeremy Krimmel

Date lesson to be taught:

Grade level:

TEKS addressed:

Concept:

Objectives:

Students will be able to…

Materials list and advanced preparations:

Safety:

Engagement

What the Teacher Will Do	Eliciting Questions	Student Responses
Write the word “clownfish” on the chalkboard.	What is a clownfish? What is its scientific classification?	[a saltwater fish], a freshwater fish [kingdom Animalia, phylum Chordata]
Ask each student to contribute 1 organism that eats or is eaten by a clownfish or a previous contribution by another student	What eats a clownfish? What does a clownfish eat?	[predators of the ocean like bigger fish, sometimes possibly sharks or whales] [anemones, algae, zooplankton], other fish, etc.
Ask students what the figure they just created is called	Why is it important?	[a food web] [shows how different organisms are related, either directly or indirectly]

Exploration

What the Teacher Will Do	Eliciting Questions	Student Responses
Explain to students that they will come up with hypotheses for what might happen to the other organisms in the food web that the class had just created if an organism were to go extinct		Students break up into groups of 3
Divide students into groups of 3 and ask the students to come up with hypotheses for 5 different organisms per group, 2 directly connected, 3 not	How could the loss of one organism affect another? What if they aren’t directly connected on the food chain?	[Predators of the extinct organism decrease in population, prey of the organism increase in population]
Ask each group to come up with 1 physical event or environmental change that could result in the extinction of the predetermined organism	Is it plausible for this event to affect only this single species?	[meteorite impact, global warming], loss of food (why did it lose it’s food), etc.
Lead the students in presentation of their possible reason for extinction to the rest of the class, and write them all on the chalkboard	How likely is this event? How many different species would this affect?	Present their hypothesis to the class
Tell students to perform the “Extinction Events” activity (attached) in their groups; wander between groups helping them along while they are performing it		Perform the activity in groups

Explanation

What the Teacher Will Do	Eliciting Questions	Student Responses
Ask the students to present their answers to particular questions, each group will answer a different question	Questions can be found on the “Extinction Events” activity sheet	Student responses will be varied and possibly complex
Explain that many mass extinction events have occurred throughout history and go into more depth about the Permian-Triassic Extinction	Over what period of time do you think these extinctions occur?	[extended periods of time], brief, instantaneous periods of time

Elaboration

What the Teacher Will Do	Eliciting Questions	Student Responses
Pass out to the students sheets that explain the competing theories for the P/T extinction	Which theory do you believe to be correct? Why?	Students will pick different responses for different reasons

Evaluation

What the Teacher Will Do

Eliciting Questions

Student Responses