These aren’t the pests you’re looking for

Day after day, week after week, special agents keep a look out for invaders that they really don’t want to find. And we, the ordinary public, give them barely a second thought. Worse, we sometimes provide the means for the invaders to get in. Of course when it all goes wrong, there’s an outcry, as there has been for the Mediterranean fruit fly, the European corn borer, the giant African snail and many other pests. Most of the time, however, we remain blissfully unaware. And most of the time, pes...