'''The Novel (1851)'''

* ScienceMarchesOn: While the author was very knowledgeable about cetology, some "facts" he used have since been proven to be inaccurate.
-->"Be it known that, waiving all argument, I take the good old fashioned ground that the whale is a fish."
** More of a case of ''definitions'' march on. "Fish" originally just meant "animal that lives exclusively in water". Melville recognises that whales are warm-blooded, breathe air, and bear live young, but just doesn't think that a sufficient reason to redefine what "fish" means.
** He also mentions phrenology and physiognomy, both now considered pseudosciences.
** Chapter 105 poo-poohs the notion that whaling might endanger the whale population.

'''Film Version (1956)'''

* Orson Welles was actually battling depression at the time of filming, and had to be coached through his lines by director John Huston
* PlayingAgainstType: The primary reason that the 1956 version wasn't well-receieved initially was that audiences weren't comfortable seeing Gregory Peck as a villainous character (albeit an AntiVillain). Patrick Stewart and William Hurt faced no such problems.
* WhatCouldHaveBeen: William Holden and Robert Mitchum were both pitched as possible alternatives to play Ahab, as they didn't think Gregory Peck was capable of playing a villainous character. Interestingly enough, Peck himself thought that director John Huston would have made the perfect Ahab.

'''TV Version (1998)'''

* HeyItsThatGuy: Ahab is [[Series/StarTrekTheNextGeneration Captain Jean-Luc Picard]] and Ishmael is played by [[Film/ETTheExtraTerrestrial Elliot]]!

'''TV Version (2011)'''

* BillingDisplacement: Ethan Hawke was billed over William Hurt for playing Starbuck.