Resource Image

Processes that Regulate Patterns of Species and Genetic Diversity

Author(s): Jillian K. Decker

State University of New York - Rockland Community College

820 total view(s), 1186 download(s)

0 comment(s) (Post a comment)

This activity was developed for an undergraduate upper level ecology course for Environmental or Biological Science majors. Classes of ~20 students work best for the activity.

Licensed under CC Attribution 4.0 International according to these terms

Version 1.0 - published on 29 May 2019 doi:10.25334/Q47M94 - cite this

Adapted from: Processes that Regulate Patterns of Species and Genetic Diversity v 1.0



Over the course of multiple lecture periods, students: (1) learn basic concepts regarding island biogeography; (2) learn how to navigate Excel; (3) practice hypothesis development; and (4) simulate colonization and drift in artificial island communities to understand how these processes affect distributions of biodiversity in small versus large islands with varying degrees of isolation. Plastic baskets of varying size (large and small) represent islands, and are situated to represent different degrees of isolation. Ziploc bags of candy represent individuals in the communities and different candies inside the bags represent the genetic composition of the individuals. Students simulate colonization and drift in communities by tossing (to simulate emigration attempts), replicating (to simulate reproduction), and adding (if immigration attempt was successful) individuals from their communities. Students record baseline data by collecting quantitative data on the initial species and allelic richness on the islands and then record which individuals and candies are removed from and added to their island communities over time, analyze graphical representation of their data, and discuss whether or not their original hypotheses were supported by the data and how to best represent their data graphically.


This version of the exercise involves the same general exercise and concepts but differs in the following:

(1) it is set up to run in a lecture over the course of a week or so. The timeline of events (in numerical order) included:  

1. Homework assignment to view two Island Biogeography Videos (Youtube). 

2. A follow-up quiz that is intended to assess student understanding of the basic concepts associated with Island Biogeography learned from watching the videos. The quiz includes two questions: (1) matching: the four curves of the Graphical representation of the theory (Mac Arthur and Wilson 1967) matched with the words "large", "small", "near", "far; (2) short answer: Describe what the graph is telling us.

3. After the quiz, students spend time in small groups of 2 or 3 developing a hypothesis (use the hypothesis development pages from the original Module). 

4. Students spend a class period gathering baseline data (Islands prior to manipulations).

5. Students conduct their manipulations (tosses, replication events, etc.) during a second class period.

6. Students evaluate a graphical representation of their data as homework. 

7. There is a final class discussion on whether the data support their original hypotheses and how the data could be best graphically presented.

8. Final assessment questions as part of an exam assess student growth over the exercise and allow students to evaluate the exercise. 

(2) incorporates supplemental information (i.e. HHMI Biointeractive Excel Tutorials, videos, continuous assessment). 

Cite this work

Researchers should cite this work as follows:


There are no comments on this resource.