Abstract

Some recent developments in ecology, economics, and ethics can be brought together within a remarkably simple yet general theoretical framework. Two applications of this framework involve the effects of species diversity on ecosystem productivity, and of economic inequality on biodiversity loss, respectively. In each of these two cases, part of the overall causal relationship is mediated by a diminishing-returns relationship at the lower level (the level of the population or the person, respectively). But same-level (ecosystem or societal, respectively) and/or higher-level (landscape or inter-societal) mechanisms also come in play. In the diversity-productivity case, the proposed theoretical perspective enables one to quantify how much more "the whole is... than the sum of the parts". These aspects of the ecological and economic realms have interesting parallels in the domain of "pure" ethics.