Natural Selection PHET

1) Click on LAB

2) Click on "Rabbit Teeth" on the left under the dominant column to add a mutation.

3) Click “Add a Mate”.

4) After 3 generations have passed on the graph, pause the simulation.

Question # 1: Based on the population numbers, which type of tooth is the predominant trait so far?

• Short Teeth

• Long Teeth

Question #2: Do the current environmental conditions favor one type of tooth? Use evidence to support your answer. (Hint: the “proportions” setting next to the graph can provide evidence as well)

Question #3: PREDICT: What would happen to both the populations of long teeth and short teeth rabbits if the food became tough? What would happen to the proportion of long teeth to short teeth.

1) DO NOT RESET. Click the “tough food box”.

2) Then, click "Play" to restart the simulation.

3) After 7 generations have passed, pause the simulation to check your predictions.

Question #4: Were your predictions correct? Use evidence to support your claims.

Question #5: Write the REASONING for the following claim: Long teeth in rabbits is a favorable mutation when food sources are tough.

1) Reset everything using the "Back Arrow" button. Click on the "Fur" on the RIGHT under the recessive column to add a mutation.

2) Click “Add a Mate”. 

3) After 3 generations have passed, click "Wolves" while letting the simulation run.

4) Pause the simulation after 8 generations. 

Question #6: How did the proportion of white bunnies to brown bunnies change after wolves were introduced to the environment?  What would be a reasonable explanation for this change?

Question #7: Based on the evidence, what is the difference between a dominant trait (white fur) and a predominant trait?

1) DO NOT RESET. Click "Snow".

2) Click "Play"  to restart the simulation.

3) After 12 generations have passed, pause the simulation.

Question#8: What effect did the change in environmental conditions have on the rabbit population?

Question #9: What factors determine whether or not a mutation will become a predominant trait?