Endemism in Wyoming plant and insect herbivore communities during the early Eocene hothouse

The warm, equable, and ice-free early Eocene Epoch permits investigation of ecosystem function and macro-ecological patterns during a very different climate regime than exists today. It also provides insight into what the future may entail, as anthropogenic CO2 release drives Earth towards a comparable hothouse condition. Studying plant-insect herbivore food webs during hothouse intervals is warranted because these account for the majority of non-microbial terrestrial biodiversity. Here, we report new plant and insect herbivore damage census data from two floodplain sites in the Wind River Basin of central Wyoming, one in the Aycross Formation (50-48.25 Ma) at the basin edge (WRE) and the second in the Wind River Formation in the interior of the basin (WRI). The WRI site is in stratigraphic proximity to a volcanic ash that is newly dated to 52.416 ± 0.016/0.028/0.063 (2σ). We compare the Wind River Basin assemblages to published data from a 52.65 Ma floodplain flora in the neighboring B...