Axolotl Punnett
Squares
Name:____________________
Class #:___________________
Determining Salamander Genetics
With this worksheet, we will try to determine the genotypes of our axolotls based on expected observed
phenotypes of young from each possible cross. Please fill out the observed phenotypes of the parents
below and then the following Punnett Squares.
Observations
Cross A
Cross B
Cross C
Parent #1 Phenotype
Parent #2 Phenotype
Offspring Phenotypes
and percents
Possible Cross 1:
aa x AA
Possible Cross 2: Aa x AA
Parent #1
a
a
A
Aa
Aa
A
Aa
Aa
Parent #2
Parent #2
Parent #1
Possible Genotypes
Aa
Possible Genotypes
Percent likelihood of
each Genotype
100% Aa
Percent likelihood of
each Genotype
Possible Phenotypes
Wild Type
Possible Phenotypes
Percent of each
Phenotype
100% Wild Type
Possible Cross 3: AA x AA
Percent of each
Phenotype
Possible Cross 4: aa x Aa
Parent #1
Parent #2
Parent #2
Parent #1
Possible Genotypes
Possible Genotypes
Percent likelihood of
each Genotype
Percent likelihood of
each Genotype
Possible Phenotypes
Possible Phenotypes
Percent of each
Phenotype
Percent of each
Phenotype
Possible Cross 5: aa x aa
Possible Cross 6: Aa x Aa
Parent #1
Parent #2
Parent #2
Parent #1
Possible Genotypes
Possible Genotypes
Percent likelihood of
each Genotype
Percent likelihood of
each Genotype
Possible Phenotypes
Possible Phenotypes
Percent of each
Phenotype
Percent of each
Phenotype
Follow-Up
Based on the expected results from each of these Punnett Squares, infer what crosses we actually made
based on the phenotypes of the parents and expected percents of the young.
1. Which possible crosses are you confident were not any of the crosses we made? Explain in several
sentences why you think this is the case.
2. What Possible Cross was Cross A? Explain in several sentences why you think this is the case and
how you eliminated the others.
3. What Possible Cross was Cross B? Explain in several sentences why you think this is the case and
how you eliminated the others. (There are two that make sense.)
4. What Possible Cross was Cross C? Explain in several sentences why you think this is the case and
how you eliminated the others.
5. For Cross B, there are two possible crosses that fit. What follow-up crosses could you make to figure
out the genotypes of the parents?