The USGS Wyoming Cooperative Fish and Wildlife Research Unit coauthored a paper titled “Migrating bison engineer the green wave” published recently in Proceedings of the National Academy of Sciences, a leading journal publishing new discoveries across many disciplines. The Green Wave Hypothesis (GWH) says the green wave—the progression of spring green-up from low to high elevations or latitudes—dictates the pace of herbivore migrations worldwide. Animals move in sync with the wave because young vegetation provides the best forage. This month’s CRU Corner story is an article that is reprinted with permission from the U.S. Geological Survey.