Conservators working on the five lower central panels discovered that the Van Eyck brothers’ original work had been painted over as early as the mid-16th century; removal of those additions (as well as the centuries’ accumulated grime) uncovered an unsuspected level of naturalism. Says the project’s head, “Botanists can actually identify every plant in there. The ones that couldn’t be identified — those were overpaintings.” – The Art Newspaper