Name: ____________________________________ Block: _________ Date: ___________________
Natural Selection Simulation


Log on to: http://phet.colorado.edu/simulations/sims.php?sim=Natural_Selection
Click on 'Run Now!' to launch the simulation
Exploration
Directions: Explore the simulation by testing its different functions and answer the questions below.
1. What are some things that you have control over in the simulation?
_________________________________________________________________________________
_________________________________________________________________________________
2. What happens to the bunny population if a friend is never added? Why is this?
_________________________________________________________________________________
_________________________________________________________________________________
3. What happens when you add a friend? __________________________________________________
4. What happens to the population if the food is super abundant and there are no predators?
_________________________________________________________________________________
_________________________________________________________________________________
5. What is a genetic mutation? Write the definition. ___________________________________________
_____________________________________________________________________________________
Simulation
Directions: Run the following 8 experiments. After each experiment, summarize in the chart what happens to
the bunny population after you add the natural selection factor. Note: F3 refers to the third generation...this is
represented by the third “spike” on the graph on the simulation.
Experiment A
 Add a friend and a brown fur mutation to the bunny population.
 Add the (natural) selection factor* of wolves after F3 offspring appear.
Experiment B
 Add a friend and a brown fur mutation to the bunny population.
 Add the (natural) selection factor of food after F3 offspring appear.
Experiment C
 Add a friend and a long teeth mutation to the bunny population.
 Add the (natural) selection factor of wolves after F3 offspring appear.
Experiment D
 Add a friend and a long teeth mutation to the bunny population.
 Add the (natural) selection factor of food after F3 offspring appear.
*The
(natural) selection
factors used in this
simulation are most often
referred to as “limiting
factors” by most
scientists.
Experiment E
 Repeat Experiment A in the Arctic Environment.
Experiment F
 Repeat Experiment B in the Arctic Environment.
Experiment G
 Repeat Experiment C in the Arctic Environment.
Experiment H
 Repeat Experiment D in the Arctic Environment.
Results
Experi
ment
Describe population changes after the natural selection factor was added.
A
B
C
D
E
F
G
H
Conclusions
6. Define variation. What genetic variations are presented during this simulation? ___________________
__________________________________________________________________________________
__________________________________________________________________________________
7. Define adaptation. ___________________________________________________________________
__________________________________________________________________________________
8. Give two examples when an adaptation is beneficial to the bunnies in this simulation.
__________________________________________________________________________________
__________________________________________________________________________________
__________________________________________________________________________________
9. Besides food and predators, describe three other factors which affect animal populations in the real
world. _____________________________________________________________________________
__________________________________________________________________________________
__________________________________________________________________________________
10. How does this simulation demonstrate evolution by natural selection?
__________________________________________________________________________________
__________________________________________________________________________________
__________________________________________________________________________________