The most sensitive frequencies are at the resonant frequencies of the auditory canal. In other words, the ear has shaped itself to naturally amplify certain bandwidth. And that corresponds to sounds in that bandwidth that were most important to our evolving ancestors to hear, in order to survive. And it doesn't match the human voice. It matches birdsong.

I believe that our distant nomadic ancestors came forward and survived because they could hear distant, faint birdsong as an acoustic navigational beacon, if you will, and by moving toward the birdsong, they were able to find places with shelter, food, and water, and a prosperous growing region. Indeed, birdsong is the number one indicator of habitats prosperous to humans.

We're all born listeners. And as a result of our modern lives, and living in a world that has less meaning than the natural world that we evolved to hear, we learn to think of listening not as taking in all the information with equal value, which is the definition of true listening. In our modern world, we tend to think of listening as focusing our attention on what is important and filtering out everything else.

We think the problem is out there, when the problem is really in here - who we are and how we experience the world around us. The acoustic ecologist listens, as the primary sense, to the world around us, and I believe that they have a significant contribution to make to all environmental groups who think that they're solving environmental problems, when we're actually all on a spiritual pilgrimage.

I work in the same style as classic landscape photographers. You find the right perspective, and then you wait until the light is right. I do the same. I find the right location, and then I wait for the sound, the atmosphere to be right, and for the space to be revealed.

You don't really need to engage your visual sense, because the natural wiring of the human psyche is to monitor the environment through sound, not through sight. But we're convinced through modern conditions that we have to look at everything, and that creates stress in our life, because we're trying to solve problems in ways that are much more time consuming, not efficient, and not fun.

The most important thing for our species is, before it speaks, to listen to its environment. That has a higher priority in any species' survival. We need to be listening to our environment - in other words, restoring the quiet - not just to our natural areas, but also to towns like Portland, Maine.