This is a book about ecosystems: the ways in which we perceive them, conceptualize them,protect them, and manipulate them. Ecosystems have been given considerable attention inrecent literature, and with good reason. Our growing comprehension of irreplaceable andimperiled ecosystem services has made it clear that we are in the midst of an ecological crisis.In response, various organizations, agencies, and individuals have dedicated themselves to thepreservation, restoration, and maintenance of ecological systems. The United States is a worldleader in this regard, building upon the legacy of giants like Thoreau, Muir, and Leopold.And yet, even as we scramble to rehabilitate and sustain ecosystems, the debate on their naturecontinues. In one corner are proponents of holismthose that see ecosystems as definableunits with recognizable and regenerative stable states.