Heatstroke is an important and useful addition to the library on climate change, bringing insights from deep-time ecological research to help illuminate the dire forecasts of which we're already so aware.

Wallace's sales agent, back in London, heard mutterings from some naturalists that young Mr. Wallace ought to quit theorizing and stick to gathering facts. Besides expressing their condescension toward him in particular, that criticism also reflected a common attitude that fact-gathering, not theory, was the proper business of all naturalists.

Kill off the sacred bear. Kill off the ancestral crocodile. Kill off the myth-wrapped tiger. Kill off the lion. You haven't conquered a people, or their place, until you've exterminated their resident monsters.

Results "are no good unless they answer (or can be made to seem to answer, or can be twisted and wrenched and piled into odd shapes until they hint at being somehow perhaps on the verge or answering) a question that someone might conceivably want asked."

And so in 1975, the grizzly bear was put on, as I said - on the endangered species list as threatened. And new measures were taken, for instance, bear-proofing garbage, creating new regulations to - essentially to try and keep people and people's food away from the bears, let the bears adjust to eating the abundant wild food that's available in Yellowstone and allow them to be more wild, to be independent of humans as sources of foods for the good of both sides. And that has been quite successful.

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.

Among the earliest forms of human self-awareness was the awareness of being meat.