APES Island Biogeography Lab
Name________________________________ Per. __
I.
Introduction: MacArthur and Wilson developed the theory of island biogeography
by counting species on different size mangrove islands on the Florida Coast. We can
recreate their data on species colonization by creating islands and colonizing them
with bird seed.
II.
Materials:
 Chalk
 Bird Seed
 Parking Lot (blacktop)
 Meter sticks
III.
Procedure:
1. Identify the starting spot in the parking lot/blacktop, this is your MAINLAND.
2. Draw an assortment of different size islands on the asphalt, vary their distance
from the Mainland.
3. Stand on the Mainland and toss handfuls of bird seed toward the islands.
4. After all seed is tossed return to all the islands you drew. Record the following
attributes of the island.
A. Size of island
a. Small island (less than 30 cm in diameter)
b. Medium island (30 cm – 1 meter in diameter)
c. Large island (greater than 1 meter in diameter)
B. Distance of island from mainland, to the nearest ¼ of a meter.
C. Total colonization (each seed that lands on an island means a
species colonized the island).
5. Combine all of the class data. Generate two graphs in the data section
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IV. Data
A. Graph the number of species on each island on the Y Axis, graph the size of the island on
the X Axis. Make your graph a histogram. Label each Axis.
Title: ___________________________________________
What is the dependent variable for this graph? ____________________________
What is the independent variable for this graph? ___________________________
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B. Graph the number of species on each island on the Y Axis, the distance from the
mainland on the X Axis. Draw a best-fit curve.
Title: ________________________________________
What is the dependent variable on this graph? ___________________________
What is the independent variable on this graph? __________________________
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V.
Conclusion
1. Each island has an equilibrium point for an ideal number of species. What would
happen to an island’s community if a new species colonizes an island already at
equilibrium?
2. What other ecosystems resemble islands? List at least two and explain why they are
similar to islands.
3. Based on your data would you recommend your community generate a few small green
spaces for wildlife habitat, or one single large green space for wildlife? Why do you
suggest this?
Modified from AP Summer Workshop
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