Combination Joke

A joke that combines typical joke genres.

A combination joke can merge any number of joke generes.

E.g.

Doctor doctor + why did the chicken cross the road.
Intelectual + childish.
Knock knock + yo mama.
A man walks into a bar + how many does it take.

This combination joke incorporates the Knock Knock, Yo Mama, and Intelectual genres.

A: "Knock knock"
B: "Who's there?"
A: "The Origin Of Species"
B "The Origin Of Species Who?"
A: "...Who is also yo mama!"