A dominant trait is NOT always the more common trait because

Question

A. sometimes the dominant allele is rare ~ so it rarely shows up

B. there are many of them and they show up frequently

Answer 1

A. sometimes the dominant allele is rare ~ so it rarely shows up

This statement explains that a dominant trait, while it can be expressed in individuals with just one copy of the dominant allele, does not necessarily mean that it is common in the population. If the dominant allele is rare, then the corresponding dominant trait will also be less frequently observed in the population. On the other hand, recessive traits can sometimes be more common if the recessive allele is more prevalent.