The earth has continued to change, from rapid climatic changes that have caused the glaciers and the ice sheets to basically bulldoze the landscape and cause species compression in the tropics and cause mass species extinction - you know, all these huge changes. In terms of evolution, every species is doomed to eventual extinction. The natural world is constantly changing. So, to deal with "environmental problems," in quotes, totally misses the issue. That is not the way we want to define our problem if we're going to find our solution.

I used to hate the urban environment and the urban din. But I realize now that it's really not that much different than living next to a waterfall for wildlife. Most wildlife - unless they're specifically adapted - avoid being around a waterfall or whitewater streams and rivers because it jams their sense of surveillance. They are more vulnerable, and their message loses intelligibility. Now, the ouzel is able to overcome that in various ways. Back to the urban environment, we're talking and delivering messages as if we weren't next to a waterfall, and that's a problem.

The normal way of gathering information is through sound: when you hear information that you want to gather, you look in its direction, you see what it is, if you choose you can get closer, you can see it, you can touch, and then, finally, the most committed form of data gathering is to taste it and eat it. But for the urbanite, we're cut off from our primary sense, and I want to stress that - our primary sense of gathering information about the place that we're living in - and instead, we're in a war zone.

You can listen to a birdsong, and from the content of the birdsong, you will be able to determine whether or not the bird grew up in a noise-polluted environment or whether it grew up in a pristine, clean environment. Isn't that incredible?

Acoustic ecology is the study of information systems: the shared acoustic environment and how species send and receive messages in this shared acoustic environment. What these messages mean - meaning, what are the consequences and the changes of behavior in any species. And it has as much to do with us individually and biologically as it does with the shaping of cultures and beliefs.

Not only does the modern person often think that sight is more important than sound - there's no objective evidence to indicate that. Many people, even audiologists who study the science of human speech and hearing, have assumed for a long time that the human ear evolved to hear the human voice, rather than the voice changing to fit the human ear. And the human ear is actually not a perfect match if we map its sensitivity to the different frequencies in the human range of hearing; it's an unequal curve, it's kind of a wavy line.

I'm very thankful, hearing impairment or not, that I've brought listening into my life. I will never say that I'm a good listener, however. Thinking that I was a good listener was one thing that kept me from being a good listener. It's a very dangerous thought. I just want to be better.