Remember the monk and the peas? The story introduced school children to genetics long before the human genome made the evening news. The Augustinian monk Gregor Mendel conducted hundreds of experiments on the edible pea, crossing peas that were smooth or wrinkled, peas that grew tall or short, peas that had white or violet flowers. He found that the results of these crosses were predictable, and in 1865 he presented his findings to the Brunn Society for the Study of Natural Science in Moravia (1). But there was little reaction to Mendels report, and his next experiments took a different turn. Mendel sent his report to a famous botanist in Munich, Karl Wilhelm von Nägeli. The botanist replied, but his letter encouraged Mendel to examine ...