Conservation is, among other things, the expression of a relationship between humans and nonhuman nature. This relationship can be described empirically using the methods of social science, but it can also be prescribed in the form of philosophical arguments. Scholars in the field of environmental ethics have discussed and debated how we should relate with nonhuman nature, formulating different accounts of an “environmental ethic.” While these accounts are highly variegated, many of them suggest humans have at least some direct moral obligations to at least some part(s) of nonhuman nature. Scholarship in environmental ethics is generally offered up with the presumption that, if people accepted and affirmed the tenets of an environmental ethic, they would then engage in more environmentally sustainable conduct. In this way, a clear link is presumed between ethical commitments and manifest behaviors. Recently, many in the conservation community have made a similar presumption, but in a radically different form. Proponents of “new conservation” or “ecosystem services” assume that 1) people are largely anthropocentric (i.e., ethically “human-centered”), and therefore 2) appealing to the human benefits of nonhuman nature will most effectively elicit support for conservation. This line of reasoning presupposes that support for conservation (a form of human behavior) is directly motivated by people’s ethical commitments. Each in their own ways, environmental ethicists and new conservationists/ecosystem services enthusiasts attribute a strong behavioral influence to morality, largely disregarding the complex tapestry of social, situational, and psychological factors that also shape human behavior. The overarching objective of this work is to appraise how this larger context affects not only the expression but also the content of our ethical commitments, specifically as they pertain to the human relationship with nonhuman nature. Chapter One tests the new conservationist claim directly. The chapter reports findings from an online survey investigating how the type of beneficiary (human, nonhuman, or both) depicted in conservation outreach messages affects two metrics of support for conservation: attitudes toward the message and donations for a conservation organization. Results suggest messages highlighting only humans as conservation beneficiaries may not most effectively generate social support for conservation, but that social and situational variables other than the value basis of persuasive appeals may also influence their effectiveness. Chapter Two assesses the ethic-behavior linkage more generally, drawing on psychological research to question whether or under what conditions an environmental ethic might engender pro-environmental behavior. The discussion in this chapter suggests that an ethic, and the influence it exerts over behavior, is likely to be strongly limited by psychological, social, and structural factors. Chapters One and Two situate ethical commitments alongside a host of other variables that may influence individual human behavior. Chapter Three, finally, situates (philosophical) ethical reasoning alongside other variables that may influence the content of ethical commitments themselves. The chapter analyzes additional data from the survey featured in Chapter One to empirically investigate an influential line of normative theory in environmental ethics, called “extensionism,” which is predicated on the philosophical imperative of rational consistency. Results challenge extensionist theory as a descriptive explanation for survey respondents’ beliefs about value in nonhuman nature, suggesting such beliefs arise less by the pure exercise of rational deliberation prescribed by philosophers, than by a confluence of psychological processes. Altogether, this dissertation presents morality as a highly constrained, social and psychological phenomenon of human life. But this work also maintains that environmental ethics is an important aspirational endeavor, the value of which supersedes any significance it has (or lacks) as a descriptive account of human conduct