I assume dissecting corpses helped in the research and discovery, but what about functions that require a living a specimen?
In: Biology
Leonardo de Vinci did a lot of the early research by (illegally) cutting open cadavers and documenting what her found. This allowed him to get the shapes and locations of many of the internal organs and speculate on their functions. When the local authorities found out what he was doing, he was forced to stop (on threat of imprisonment, the church getting involved, etc etc).
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