1. Lynx & Hare Learning Objectives 1.Students will be able to calculate population density. 2.Students will be able to graph the size of a population over time. 3.Students will analyze the factors (biotic and abiotic) influencing population size and/or limiting population growth. 4.Students will analyze a population graph to identify areas of exponential growth and/or carrying capacity.

2. Lynx

3. Arctic Hare

4. Predator & Prey

5. Predator/Prey Relationship  What happens to a predator population when the prey population increases or decreases?  What happens to a prey population when the predator population increases or decreases?

6. Your Task 1.Your goal is to model changes in Lynx & Hare populations 2.Mark off your square with tape (2’ x 2’). This is your habitat 3.Use the Lynx and Hare cards to model how the numbers of individuals change over time

7. Important Reminders  Take care of the materials in this lab as several class periods will be using them.  Do not misplace, throw-away, crumple or otherwise destroy the one- inch snowshoe hares. Thanks for your help!

8. Analysis: Population Growth Population Growth is affected by: 1.Births 2.Deaths 3.Number who leave or enter the population

9. Real Lynx & Hare Data

10. Question: What was affecting the population of the lynx and hare in the activity?

11. Exponential Growth J-shaped growth In ideal conditions, a population will start growing slowly, then exponentially Example: in the right conditions, bacteria double their population each generation. Draw graph into your notes!

12. Limiting Factors Of course, organisms cannot grow exponentially for long Factors that limit the growth of a population are known as limiting factors Example: predation of hares by lynx limits the hare population

13. In the absence of lynx, what other factors might influence the size of the hare population? hare population?  Brainstorm in your groups

14. Factors can either be: - biotic (living factor) or - abiotic ( physical, non-living ) e population?  Classify each of the factors you brainstormed as biotic or abiotic.

15. Carrying Capacity  The maximum population that can be supported by an environment  The number is set by the availability of space, food, and other resources necessary for survival.

16. Carrying Capacity S-shaped growth As a result of limiting factors, population growth slows, or stops The result is a S- shaped curve The top of the curve is K (carrying capacity) Draw graph into your notes!

17. Example of S-shaped curve Question: what do you think might happen if a population exceeds the carrying capacity?