I found these chapters much more interesting and easy to get through than the first three chapters. I agree with their use of "ecology" rather than "community." Communities can be static, while ecologies never are.

I really found the notion of keystone species interesting, as well as their observation that keystone species are often unrecognized and unappreciated. The humanity behind technology is part of this, and one reason why I argued in my previous post that technology will never get out of hand. This idea especially struck me because one of the things my parents and other family members who are successful in the work force have taught me is that social skills are a huge part of any job. You can be the most brilliant stock analyst in the world, but if you're abrasive and rude and can't communicate, you're not likely to be very successful because no one wants to deal with you. This seems to fit perfectly with the "unappreciated humanity" idea, especially in results-oriented America. Any successful part of business depends on undocumented humanity.

I also liked this: "But each can speak up in his or her own ecology." That's another way to put the common saying that "No one can do everything, but everyone can do something." Nardi and O'Day give the idea a background and examples of how that saying really is true. They hammer it home more than the saying itself.