As I started to read nonfiction in the mid '70s, I discovered, holy cow, there was a lot of imaginative nonfiction. Not the kind where people use composite characters and invented quotes. I hate that kind of nonfiction. But imaginative in the sense that good writing and unexpected structure and vivid reporting could be combined with presenting facts.

But private lands development around the periphery of the parks - Grand Teton and Yellowstone - is a crucial issue because if those private lands are transformed from open pastures, meadow, forest land to suburbs, to little ranchettes, to shopping malls, to roads, to Starbucks - if those places are all settled for the benefit of humans, then the elk are not going to be able to migrate in and out of Yellowstone Park anymore. And if the elk can't migrate into the park, then that creates problems for the wolves, for the grizzlies, for a lot of other creatures.

I used to read only fiction. Now I don't read much, only occasionally, such as a Cormac McCarthy or a Jim Harrison novel.

Identity is such a crucial affair that one shouldn't rush into it.

If you're Maasai Mara National Park in Kenya, if you're in Serengeti National Park in Tanzania, you don't get out of your vehicle and go walking around amid the lions and the leopards. You stay in your Land Rover. You stay in your safari van, and you look out the windows or you look out the pop top at these animals. I know by experience how badly that can work out if you violate those guidelines.

[Theory is] an explanation that has been confirmed to such a degree, by observation and experiment, that knowledgeable experts accept it as fact. That's what scientists mean when they talk about a theory: not a dreamy and unreliable speculation, but an explanatory statement that fits the evidence. They embrace such an explanation confidently but provisionally - taking it as their best available view of reality, at least unil some severely conflicting data or some better explanation might come along.

Whether you like the label 'Anthropocene' or not, whether you find the prospect of what it signifies inevitable or appalling (or both), the time has come to address its implications, as these thoughtful, battle-tested authors attempt to do. The time has long since come.