Warm, Warm on the Range

Global warming is a very real phenomenon and most agree that human activities have contributed to an increase in the minimum daily temperature. In this issue, Alward et al. demonstrate that this increase in minimum temperature causes a distinct change in the mix of plants found in a prairie grassland in the Midwestern United States. In his Perspective, Mellilo describes other examples of warming9s effect on ecological systems and explains how we can best study these changes.