Natural Selection
The Natural Selection simulation allows students to engage in scientific thinking about genes, traits. mutations, and selection agents. Students can compare the distribution of bunnies over time and hypothesize about which traits may be favored in different conditions.
Intro Screen
In the Intro screen, students can be introduced to natural selection by focusing on just one mutation
SELECT equator or arctic
Add Mutation ADD a dominant Dominant Recessive I or recessive Fur mutation Environmental Factors Wolves Limited Food 1ADD wolves and/ or limited food to the environment
environment
ADD A MATE tO watch the population grow
Add a Mate
Totel
-White Fur Brown Fu Data Probe
ViEW population OPropartions graph over time, O Pedigree DuON relative proportions of traits,or pedigree PHET: chart
PROBE the population chart to get exact numbers of bunnies Natural Selection
Generation
Lab Screen
In the Lab screen, students can explore the relationship between additional mutations and environmental factors.
WATCH the bunnies in their environment
RECALL if a mutation is dominant or recessive
Tooth
Environmental Factors Wolves Tough Food Limited Food
ADD wolveS, tough food, and/ or limited food to the environment
COMPARE the presence of different traits
White Fur Brown Fur Straight Ears FOppy
FR
Teeth
190%
Start of Generation 318 bunnies
O Population Proportions O Pedigree O None
Short Teeth Long Teeth
SPEED up time I by pressing and holding PHET:
VIEW past or current data
Generation 11
Natural Selection
McGarry, September 2020
Model Notes
: Floppy ears have no selective advantage and are representative of mutations that can occur but are not advantageous. - Limited food does not select for any particular phenotype, but rather functions as a carrying capacity. : The pedigree displays the alleles for each bunny. The left allele IFTt FFTT X X
FIT
on the left. The right allele represents the "mother" and the allele that was inherited from the parent on the right. - For a full model description and simplifications, see the model description.
Customization Options
The following query parameters allow for customization of the simulation, and can added by appending a '?' to the sim URL, and separating each query parameter with a " & '.
Query Parameter and Description
Examples
allelesVisible - when set to false, allows you allelesVisible=false to hide alleles from appearing in the Pedigree.
introPopulation - specifies the initial population of bunnies for the Intro screen (up to 750 bunnies).
introPopulation-2
introMutations - specifies the mutations that appear in the initial population of bunnies for the Intro screen. Must be used with introPopulation.
introMutations F&introPopulation-lff
introMutations-f&introPopulation=5Ff
TabPopulation - specifies the initial population of bunnies for the Lab screen (up to 750 bunnies).
labPopulation=l0
labMutations - specifies the mutations that labMutations Ft&labPopulation=lffTt appear in the initial population of bunnies for the Lab screen. Must be used with labPopulation. labMutations=fEt&labPopulation=5FfEe TT,l0ffeeTt
screens - launches the screens listed after the ='. Each screen should be separated by a comma. For more information, visit the Help Center.
screens=2
Suggestions for Use - Explore differen