Linking the historical roots of environmental conservation with human and wildlife health.

We examine the historical and philosophical roots of environmental stewardship and how they relate to conservation and human health. Concern for the environment in the United States derives from two distinct historical ideologies that we term ‘‘green’’ and ‘‘brown’’ environmentalism. We propose a modern-day synthesis of these ideologies that recognizes that environmental degradation and the emergence of zoonotic and epizootic diseases, affecting both humans and wildlife (i.e., pathogen pollution), are interconnected. This interconnection provides a compelling new reason to protect and preserve biodiversity.