Response of plant-insect associations to Paleocene-Eocene warming

The diversity of modern herbivorous insects and their pressure on plant hos ts generally increase with decreasing Latitude. These observations imply th at the diversity and intensity of herbivory should increase with rising tem peratures at constant Latitude. Insect damage on fossil Leaves found in sou thwestern Wyoming, from the Late Paleocene-early Eocene global warming inte rval, demonstrates this prediction. Early Eocene plants had more types of i nsect damage per host species and higher attack frequencies than Late Paleo cene plants. Herbivory was most elevated on the most abundant group, the bi rch family (Betulaceae). Change in the composition of the herbivore fauna d uring the Paleocene-Eocene interval is also indicated.