It is invigorating and disquieting to realize all of the unbroken surfaces and unseen depths that we are surrounded by. Don a diving mask and snorkel and plunge into just about any stream and, provided its waters are clear, you will envelope yourself in a world known to relatively few - dace quiver and rock in fast eddies; suckers lie on the bottom like the underwater equivalent of beached whales; and large-mouth bass shark in the water column. Your body is nearly weightless and “down” is suddenly downstream rather than towards the center of the earth. Your ears, which seconds before may have gathered the dull grind of some engine, a clutter of human voices, the familiar exclamations of birds or the whistle of the breeze, are now filled with the currents' drone which is occasionally cracked by your hollow breathing. You have broken through a surface and, although it may be in water no deeper than your knees, have plunged to new depths.
 
Such streams of novel experience are all around us: take up the time-honored (by children at least) habit of stone-flipping, and you'll find bright-eyed, lithe-bodied salamanders; swarming colonies of ants intent on the complex business of being ants; hairy spiders clutching egg pouches; iridescent ground beetles who have mastered scuttling. Set up a bright light and white sheet, then pull up a lawn chair to watch and listen: you will soon intercept a fluttering stew of night fliers - moths the colors of lichens, leaves, bark, and stone; bandy-legged crane flies that look like giant mosquitoes; carpets of midges; stoneflies with over-sized wings; and more of those ground beetles. Meanwhile, the night around you is filled with clicks, trills and rhythmic rasps thanks to a community of insects intent on conversation.
 
Indeed, the surfaces of liquid unknowing are even closer than that. Spend time walking a familiar path with a dedicated birder or avid botanist, and you’ll soon realize that they are living in a very different world from you. In the distinct depths that they inhabit, unseen birds proclaim their identities, and sometimes more, from hidden perches; leaf patterns talk of soil and human history; and comparisons of calendar dates and bird song repertoire or flower color palette hint at changing seasons, changing climates. The surface your companion crossed was not between air and water or even between night and day. It was, instead, a boundary of friendship with parts of the world that many don't even realize can be befriended; it was a pin-prick of knowing that popped an invisible, thin skinned, yet utterly smothering bubble that had once encircled their heads and still encapsulates yours.
 
Popping these bubbles, breaking those surfaces is worth doing for the personal rewards it can bring - quite suddenly you find yourself listening to an orchestra of beloved tunes or visiting an exhibition of familiar paintings. But there is more than those immediate rewards which beg us to undertake such exploration: there are robbers in the museum, kidnappers with muffling socks stalking the orchestra pit. All of the worlds so far described - life below the water, nocturnal insects, flitting birds, flowering plants – and many more have changed dramatically over the past centuries, decades, years. Some of those changes have been biological ripples from the moving of geology's immense snail; they have been changes to which we are little more than befuddled spectators. However, many of the more recent changes have stemmed from our own hand. And yet, despite this personal responsibility, we very often do not have the eyes to see what we have wrought.
 
In these days of seething clouds of information, it is difficult both to find the peace needed to prick bubbles and also to accept that the multiplication of words, numbers and keystrokes represents more a turning up of the volume within our own head phones than it does exploration of truly new worlds. In an era when we seem to know everything, how do you convince someone that we have little knowledge of where those minnows go when floods, perhaps exacerbated by our own doings, transform clear creeks into mud-filled torrents? How do you show someone that the bounds of zoological knowledge are at our backdoors where some of the tiny moths at the light are unnamed by science, mystical in their ways, and yet buffeted by our reworking of the land? How does one express the urgent need for such apparent trivia when society has positioned pursuit of it so far from the prestigious cutting edge? We are marching loudly on the Earth but not taking the time to listen to our own footfalls. We are splashing across streams in our protective rubber boots without ducking below the surface to see what we are stepping on.
 
I am getting old enough to see behind me my own short path of wandering. Old enough to regret certain choices and wonder at which ones I will still have the luxury to make. But if there is one theme, one strain, one melody that I hope will not fade from my future and that I hope young people will continue to embrace, it is the sound of listening to the unknown; the sight of seeing the unseen. It is the very act of deep diving, of realizing for the sake of humility, for the sake of responsibility, for the sake of the glorious exhilaration of exploration, that we are surrounded by the rippling surfaces of uncounted lakes of inviting infancy.