Imagine that you are a doctor in a maternity ward. During your last shift, 20 babies were born. 10 had blue eyes, and 10 had brown eyes. Remember genotypes are the two alleles given for each trait, written with a letter. For this activity B =brown eyes b= blue eyes. Phenotypes are the physical appearance of the trait. What percentage of babies have Brown and Blue eyes (to find percent divide the total number of blue-eyed babies by the total number of babies born.