Dates	Actual Protists per Slide	Predicted Protists per Slide
10/1/2007	14	14
10/3/2007	11	25
10/8/2007	4	26
10/15/2007	20	23
10/17/2007	46	11
Answer the following questions directly on this spreadsheet:
1.  Compare the appearance of your two graphs - did they follow roughly the same pattern; were the patterns different?
How do these graphs describe the protist populations changing?
2.  Assuming your results are accurate, what biological factors might have influenced the protist populations?
3.  Explain all possible sources of error in your data - what kinds of mistakes might you have made?
What kinds of errors might have resulted because of the methods we used?
What sorts of external conditions might have given us inaccurate results?
4.  In comparing your raw data (from your datasheets) how have the populations of small, medium, and large
protists changed over time?  Have any groups become more abundant?  Have any groups become less abundant?
Explain how your data illustrates ecological succession.
Example Responses:
1.  The "predicted" graph shows a gradual increase in the protist population follow by a steep decline towards the end.
The actual graph shows a decline in population for …
2.  In the beginning, food might have been scarce for the protists.  Then, they ….
3.  One day, I accidentally dropped some soap into the slide which might have …
4.  The "small" protists became much more abundant …
E-mail (as an attachment) to dan.bregar@corvallis.k12.or.us with the subject "per x your name protist graph"