They both involve sell and reproduction.
All the domestic breeds of dogs that we are familiar with, from chihuahuas to pit bulls, are the same species: Canis lupus<span> familiaris. In fact, our dogs are a subspecies of </span>Canis lupus<span>, or ->*wolf*<-</span>
One factor must be dominant and one factor recessive in each individual. attached earlobes (ee). A couple both have unattached earlobes. Both notice that one of their parents on both sides has attached earlobes (ee). Therefore, they correctly assume that they are carriers for attached earlobes (Ee).