"During World War Two, in the prison camp Terezin, a group of Jewish children and their teacher planted and nurtured a smuggled-in sapling. Over time, fewer and fewer children were left to care for the little tree, but those who remained kept lovingly sharing their water with it. When the war finally ended and the prisoners were rescued, the sapling had grown into a strong five-foot-tall maple. Nearly eight years later the tree's six hundred descendants...