Natural Selection Model Lab
Graph (5 marks)
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Use an Excel spreadsheet to enter your data. Enter only numbers, not words (such as white,
yellow, etc). Then make a line graph from this data
You should put time (or generations) on your x-axis, and number of individuals on your y-axis.
All five colours of disc should go on the same graph, so make sure you also have a legend or key.
Give your graph a descriptive title (not just “Natural Selection Model Lab”)
Copy this graph into a Word document and answer the conclusion and discussion questions
below the graph in the document.
Save your work in your school account and name the document:
YourFirstName YourLastName BlockA NatSelLab (or Block B)
Ex: John Smith BlockB NatSelLab
You will be putting your document into the Flynn Hand In folder when you are finished.
Conclusions: use note form
Does the data from this lab support or refute your hypothesis? EXPLAIN. (3 marks)
For all of the discussion questions, think about the lab we did, read the relevant sections of the textbook
(use the index to find page numbers) and write your own sentences. Note that if the question is worth 3
marks, you need to give me at least 3 good ideas or facts in your answers.
Discussion Questions:
1. Although not the case in this lab, it is usually true that offspring are variations of their parents. What
are the sources of this variation? (2 marks)
2. What is a gene pool? What is the original frequency of each phenotype (trait) in the gene pool? (2
marks)
3. After the final generation, what is the new frequency of each phenotype (trait) in the gene pool? (1
mark)
4. Why is the frequency of each phenotype (trait) in the gene pool valuable data? (hint: why is it
sometimes more useful to know the frequency of red discs than just the actual number of red discs in
the population?) (1 mark)
5. Based on your data, can you comfortably state which animals are best adapted and which animals are
most poorly adapted to their environment? Explain. (2 marks)
6. In this lab did the overall population of prey go up or down? What does this indicate about the
predators? (2 marks)
7. As prey became more difficult to find the selective pressure on the predators increased. What
predator strategies, behaviours and traits do you think would be selected for in a natural population? (2
marks)
8. In class we have gone over the theory of natural selection. List each step of natural selection and
explain how this laboratory model attempts to explain or show each of those four steps. (4 marks)
9. Modeling natural selection in an artificial environment like the classroom with only one independent
variable (colour of the disc) does not accurately represent natural selection in ‘real’ environments.
Describe ONE aspect of our model which helps us understand natural selection and describe ONE aspect
of our model which you might consider to be unrealistic in a “real’ environment. (2 marks)
10. Define the term “carrying capacity” Do you think we reached the carrying capacity of the
environment (classroom) in this lab? Explain why or why not with an example from your data. (3 marks)