Fossil plant–insect associations (PIAs) such as herbivory and pollination have become increasingly relevant to paleobiology and biology. Researchers studying fossil PIAs now employ procedures for assuring unbiased representation of field specimens, use of varied analytical quantitative techniques, and address ecological and evolutionarily important issues. For herbivory, the major developments are: Late Silurian–Middle Devonian (ca. 420–385 Maaa The designation, Ma, or mega-annum, refers to millions of years ago. Also see Figure 1. ) origin of herbivory; Late Pennsylvanian (318–299 Ma) expansion of herbivory; Permian (299–252 Ma) herbivore colonization of new habitats; consequences of the end-Permian (252 Ma) global crisis; early Mesozoic (ca. 235–215 Ma) rediversification of plants and herbivores; end-Cretaceous (66.5 Ma) effects on extinction; and biological effects of the Paleocene–Eocene Thermal Maximum (PETM) (55.8 Ma). For pollination, salient issues include: Permian pollination evidence; the plant hosts of mid-Mesozoic (ca. 160–110 Ma) long-proboscid pollinators; and effect of the angiosperm revolution (ca. 125–90 Ma) on earlier pollinator relationships. Multispecies interaction studies, such as contrasting damage types with insect diversity and establishing robust food webs, expand the compass and relevance of past PIAs.
