A famous anthropologist decides to visit a Native American tribe full of men disguised as a doctor so he can study them.
At one point he feels he is accepted enough to ask: "How do you guys relieve your se*ual tension without many women around?”
"Simple, just come down to the river tomorrow and we'll show you."
The next day the anthropologist shows up and sees a group of men near a donkey. One man says "Since you're our guest, you get to go first."
The doctor not knowing what to do stands without a clue until a tribesman explains to him: "Use the donkey".
The anthropologist: "What!??"
"Yes use it, mount it."
The doctor not wanting to go against custom starts to kiss, then proceeds to make love to the donkey.
A few minutes later, a man in the group hesitantly asks "Are you almost done Doc? We need the donkey to cross the river in order to get to the brothel."
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