Part $1-$Stating theHypothesis: Which Phenotype Is Dominant?

In this activity you will examine the offspring of a genetic cross between a stickleback from the ocean $($marine stickleback$)$ and a freshwater stickleback from Bear Paw Lake.

Based on what you learned in the film, what are the phenotypes of these two parental stickleback fish? Indicate your choice with a checkmark.

Marine

$\_$ pelvic spines present

$\_$ pelvic spines absent

Bear Paw Lake

$\_$ pelvic spines present

$\_$ pelvic spines absent

If we start with the simplest assumption that the presence or absence of pelvic spines is controlled by a single gene with two alleles, how would you denote the genotype of the two homozygous parents?

Marine

Bear Paw Lake