John A. Zoidberg (voiced by Billy West), "M." D., commonly known by his surname Zoidberg, is the staff doctor for Planet Express, despite his poor understanding of human physiology and allusions to his questionable credentials. He is a Decapodian, an anthropomorphic crustacean -like species of alien. His character parodies the supposed wealth and automatic respect of modern doctors—for example, his incompetence at human medicine makes him extremely poor despite his profession, and he is implied to be frequently homeless when not at work. The Decapod (named after the actual Decapoda order of ten-footed crustaceans) are an extended parody on Yiddish culture—the bigger joke being that shellfish are not kosher. The writing riffs on the marine theme in a playfully absurd way, with just about any marine Arthropoda or Mollusca being implied to be akin to Zoidberg.