9. Hare and Lynx - Lesson Plan
- Introduce today’s activity to the students. Remind them of the definition of a population and discuss how we will be looking at how populations change over time.
- Introduce the snowshoe hare and the Canada lynx to the students. Show them pictures. Discuss their appearance, life cycle, range, habitat and diet.
- Give students the handout and read the first paragraphs together. Graph the data, either together as a class using the teacher overhead, or individually.
- Ask the students to describe some of the patterns in the graphs.
- Begin a discussion with the students about why they think these patterns exist. Allow the discussion to be open ended so long as their explanations make logical sense. The purpose of the discussion is not to decide on the true reason that the cycle exists but to encourage students to come up with a logical theory based on the evidence and what they know about ecology. Some examples of questions you may wish to ask include:
- Notice how the hare population begins to increase over time until it reaches a peak. Why do you think that the numbers of hares are increasing at this time?
- Notice how the hare population begins to decrease after the peak. Why do you think that the numbers of hares is decreasing at this time?
- In general, are there more lynx or more hares? Why?
- Do the peaks in the lynx graph line up exactly with the peaks in the hares graph?
- When the hare population increases, what happens to the lynx population? Why?
- Look at the lynx population in 1903 and 1904. Think about what is happening to the hares at this time. Is the presence of more lynx helping the hares or hurting them? Why?
- Look at the lynx population in 1904 to 1906. Why is the lynx population declining?
- Do you think that this pattern is still happening today?
- Help students summarize their theory by adding arrows and labels to the graph to explain what is happening according to the theory at different times.
- Once the students have created a logical theory, you may want to consider asking them to think of experiments that could test their theory. For example, if they believe the hares are overeating the available vegetation, then a good experiment might be to monitor the population of the hares’ favorite foods over a number of years.