Andreas Vesalius (Andries van Wesel) was a 16th-century Flemish anatomist whose work revolutionized the study of the human body. And he was able to do so because he was also a body snatcher -- and though he never would have called himself one, he was known to share hands-on tips for how to find fresh corpses. He used human cadavers for hands-on observations, and published groundbreaking, forward-thinking works about how our bodies function. And in doing so, he became the father of modern anatomy.