It takes a love-struck male swiftlet 30 days to build a delicate, cup-like nest from its saliva and attach it high up on a cave wall, whereupon it is harvested lickety-split. It takes the same swiftlet another 30 days of soldiering on to replace the stolen nest with a new one, whereupon it, too, is harvested lickety-split. I’m trying to figure out how the idea of bird’s nest soup, purported to clear up skin, improve lung function, and increase sex drive, came about in the first place. Was someone boiling a pot of water on the floor of a remote cave when, all of a sudden, one of these pearly things fell in?