The human population in the United States is predicted to grow through the 21st century. As this occurs, we will continue to fragment the natural environment with development, urbanization, and suburban sprawl. This fragmentation will divide species distributions and preclude gene transfer from one pocket of protected natural habitat to another. The fragmented habitats and separated populations will render these islands of biodiversity even more vulnerable to the impacts of diseases or the effects of climatic change. As scientists and educators, we can and must act today to help ameliorate this bleak view of the future.