Caucasian Eagle Picture

For stealing fire from the gods and giving it the mortals, the Titan Prometheus was punished by having his ever-regenerating liver eaten daily by the Caucasian Eagle ("caucasian" here meaning "of the Caucasus", specifically the Caucasus Mountains, where the punishment took place).

The Eagle itself has been alternatively depicted as a bronze automaton created by the smith-god Hephaestus.

The human liver can actually regenerate, which may mean the ancient Greeks had a fairly advanced understanding of the internal organs.
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