Whenever I hear about 9/11, I will hear, from the background of my memory, the sound of monkeys. Ericka and I had arrived a day earlier on a little, twin-prop airplane that had carried a dozen of us north from Guatemala City over the verdant canopy of Central American jungle to Tikal in Guatemala's northern province, and back in time five centuries to a Mezoamerica the jungle swallowed whole. We entered the ruins at daybreak under the silhouettes of monkeys in the treetops above us, climbed temples to look out over the jungle canopy, wondered quietly about the lifestyle of a people whose world ended before ours began and whether that world made any more sense or was in any way more satisfying than this one... Had I put pen to paper at any other time in the history of human civilization, my words would have followed another course. But as fate would have it, Ericka and I found ourselves exploring the Mayan ruins of Tikal on the 11th of September, 2001. They say every member of the generation of the 1960s remembers in perfect detail where they were the moment President Kennedy was assassinated. For a generation still in school in the 1980s, the explosion of the space shuttle Challenger was to be our equivalent. But 9/11 eclipsed even that, and for the rest of my life whenever I hear about 9/11, I will think about Tikal and hear, from the background of my memory, the sound of monkeys. Ericka and I had arrived a day earlier on a little, twin-prop airplane that had carried a dozen of us north from Guatemala City over the verdant canopy of Central American jungle to Tikal in Guatemala's northern province, and back in time five centuries to a Mezoamerica the jungle swallowed whole. We entered the ruins at daybreak under the silhouettes of monkeys in the treetops above us, climbed temples to look out over the jungle canopy, wondered quietly about the lifestyle of a people whose world ended before ours began and whether that world made any more sense or was in any way more satisfying than this one. And then the planes struck the Twin Towers. There they were on CNN on a little TV over the front desk of our guesthouse, smoke trails streaming, flames gutting the upper stories of buildings about to fall. And all I could think about was the rise and fall of empires and ages. Tikal retains much of its mystery, and while the Mayans were in many ways ahead of their time, they too vanished without a trace for generations while the irreproachable jungle swallowed what they left behind. Today it is best appreciated in the chill of early morning, to the call of bird song and the first calls of the monkeys. But what I'll never forget is the silence, and a glimpse of what remains when it all comes to an end.