Download Breeding Bunnies

Breeding Bunnies
Pre-lab Questions
In this activity, you will examine natural selection and evolution in a small population of wild rabbits. On a genetic level,
evolution is a change in the frequency of alleles in a population over a period of time.
1. On a genetic level, what is changing during evolution? ___________________________________________
____________________________________________________________________________________________________.
2. In rabbits, there is a trait for being furless (called a “naked rabbit) that is represented with a lowercase a. Is nakedness a
dominant or recessive trait? ___________________________________________.
3. The trait for having fur is represented with a capital A. Is having fur a dominant or recessive trait?
______________________________________________________________________________________________.
4. Is a rabbit with the genotype AA naked or furred? ____________________________________________.
5. Is a rabbit with the genotype Aa naked or furred? ____________________________________________.
6. Is a rabbit with the genotype aa naked or furred? ____________________________________________.
7. Create Your Hypothesis: Naked rabbits have a difficult time in the wild, because fur protects rabbits from cold winters.
The cold winters are a selective force against naked rabbits. This means that naked rabbits often die before they can
reproduce. Given this information, which allele do you think is more common in rabbits, the A or the a? _____________.
Why? _______________________________________________________________________________________________
____________________________________________________________________________________________________.
Procedure
1. You will be given an A allele card and an a allele card from the gene pool. This is the genotype of your rabbit in the
first generation.
2. As a class, record the genotypes for the entire rabbit population of the first generation on the data sheet.
3. As a class, figure out the number of A alleles and a alleles and record on the data sheet.
4. Randomly, find another “rabbit” in the countryside. Stand next to them so Mr. Franks knows you have found a
mating partner.
5. When Mr. Franks tells you to, face each other while holding your allele cards behind your backs. Together, count to
three, and then each reveal one allele. The two alleles (one from each rabbit) represent the genotype of your
offspring.
6. Go to the card swap area. You are going to turn in the cards you currently have, and take the cards that represent
your offspring (both parents will take on the new genotype.) Take your assigned seats.
7. As a class, record results for the entire rabbit population of the second generation.
8. Repeat steps 4 to 6.
9. Record results for the entire 3rd generation.
10. Keep repeating this process until you have the data recorded for 10 generations.
Data Table On BACK!
Generation
# of AA
Individuals
# of Aa
Individuals
# of aa
Individials
# of A
Alleles
# of a
alleles
Total #
of
Alleles
Gene
frequency
of A
Gene
frequency
of a
1
2
3
4
5
6
7
8
9
10
Analysis and Conclusion
1. In the first generation, what was the frequency of the A allele? ______________________________.
2. In the first generation, what was the frequency of the a allele? _______________________________.
3. In the 10th generation, what was the frequency of the A allele? _______________________________.
4. In the 10th generation, what was the frequency of the a allele? _______________________________.
5. What type of weather change happened after the fourth generation? _________________________
______________________________________________________________________________________________.
6. How did this weather change affect the naked rabbits? _______________________________________
______________________________________________________________________________________________.
7.
How did the number of a alleles change over the generations? _______________________________
______________________________________________________________________________________________.
8. How did the frequencies of each of the alleles change over the generations? __________________
_____________________________________________________________________________________________.
9. What was your hypothesis? Based on the lab data, do you need to change your hypothesis? Explain.
______________________________________________________________________________________
______________________________________________________________________________________________.
10. How are the results of this simulation an example of evolution? ______________________________
______________________________________________________________________________________________.
11. In a real rabbit habitat, new animals often come into a habitat through immigration. Others leave the area through
emigration. How might emigration and immigration affect the gene frequency of A and a in this population of
rabbits? ___________________________________________________________________________________________
__________________________________________________________________________________________________