Da Vinci studied corpses to perfect Mona Lisa, says new book
Leonardo da Vinci spent his nights in a hospital's morgue among dead bodies to perfect Mona Lisa's smile in the painting, a new book by Walter Isaacson has claimed. 'Leonardo da Vinci: The Biography' reveals that the painter peeled the skin off the corpses and studied the muscles and nerves underneath to understand how a smile begins to form.