The birds are already evolving, changing the way that they sing as a result of noise pollution. And we have yet to do that. We're still not communicating. We're not changing our words. We are not testing, not providing this new lexicon for noise-polluted areas.

Whenever you're in a natural system and you're making sound, you are putting yourself at risk. As you go up the evolutionary ladder, from insects to frogs to birds and on up into mammals, the higher intelligence recognizes that when you vocalize, you put yourself at risk. So mammals generally vocalize or make noise much more rarely than, let's say, insects or frogs. And when they do, and put themselves at risk, it has to be worth the risk, and have true meaning, such as signaling during a hunting party, calling in prey, some religious or spiritual ceremony, something like that.

I'm in love with Earth. I truly am. And so listening is not work, to work toward a better future. It's joy. To not be able to work toward a better future would be work. That would be tough.

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.

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.

How are we going to know what sounds are important before we've even heard those sounds? It's an absurd question. The only thing we can say is that we're going to base it on our past experience. In other words, modern listening doesn't inform us of anything new. It simply keeps us in the past.

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.