amanda-phet
commented
3 years ago Hi @schuyler1d . The short answer is that genetic drift was not a learning goal in this particular simulation, so the model does not allow for that to happen. You can see more about the model here: https://github.com/phetsims/natural-selection/blob/master/doc/model.md.
Limited food reduces the overall population and does not select for any particular traits, so the ratios of bunnies that die are consistent with the ratios of bunnies in the sim at that time.
One suggestion to set up a scenario that might simulate genetic drift is by loading the simulation with the following query parameters, so that the mutation is present and you have a homozygous bunny: https://phet.colorado.edu/sims/html/natural-selection/latest/natural-selection_en.html?labMutations=E&labPopulation=1EE
If you run the sim with limited food, that will prevent bunnies from taking over the world. Then you can randomly introduce wolves or tough food to simulate a bottleneck, and you might see the floppy ears take over in the population. It helps to hold the fast-forward button to run through many generations.
I hope this helps. Please let me know if you have any further questions, and I can consult the developer for more insights into the model.
I am using this wonderful PHET natural selection simulation.
I am trying to simulate genetic drift by using the neutral floppy ear phenotype, setting the interactive to limited food, and setting up a bottleneck to significantly reduce the bunny population.
So far, I've been unable to get a floppy eared bunny takeover. Is such an event possible within this simulation for some reasonable number of trials?