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What kind of Medicine did Doctor Zoidberg study?
In S1E2 ("The Series Has Landed"), Zoidberg tells Fry "Young lady, I am expert on humans." Then we learn he has no medical degree. Then we recently learned he has a doctorate in Alien Biology.
What are Dr. Zoidberg's actual credentials?*
He has a doctorate in art history and is very well-versed in alien anatomy and physiology. In Anthology of Interest, he also has mail-order degrees in murderology and murderonomy.
He has a doctorate in Art History, that's why he knew what a pentimento was in the Duh-Vinci code. But his first job was to dissect the Tritonian Yeti, after which he became the personal doctor to Professor Farnsworth.
It was in the second episode where he says he was an expert on humans. In "A Clone of My Own," he states that he has a medical degree, which he lost, in a volcano, suggesting he may not have one at all. In "The Tip of the Zoidberg," it is shown that he is only hired to fulfill his deal with the Prfessor someday, so it doesn't seem like he has any.
In the Episode "The Duh-Vinci Code" he says that he has a degree in art history. But in another Episode it is also mentioned (by the professor, I think) that he is an excellent physician concerning aliens, and is just an incompetent doctor when it comes to humans.
Clearly he states it in the first episode - he says to Fry "young lady I'm an expert on humans. Now sit down and say bgralerga." So he is clearly an expert on humans.
