Sex and the single snail

IT’S MY fifth dive of the day. I am tired, grumpy and have an overwhelming desire to be dry. We flop ungracefully over the side of the boat and fin down to the seagrass bed 20 feet below us. A large reef shark glides past, tailed at a respectful distance by a school of jacks. A triggerfish watches us curiously. A cowfish glows iridescent in alarm at the sound of our bubbles. I think, as I always do, that it’s not so bad once you’re in. But we can’t look around for long; we have more important work to do.…