FOSSIL EVIDENCE FOR PLANT ARTHROPOD INTERACTIONS IN THE PALEOZOIC AND MESOZOIC

Some of the earliest Devonian fossils of vascular plants show lesions that may be attributed to plant feeding activity by animals. This is the beginning of a more or less continuous fossil record of plant-animal interactions which extends from the Devonian to the present day. An important feature of pre-Cretaceous material is the evidence from coprolites and gut-contents of spore eating by arthropods. Experiments with living arthropods, of groups represented in the Palaeozoic, show that viable spores can survive passage through the gut in significant numbers. Spore eating could clearly have had a dispersal role of value to the plant, as well as its evident benefit as a source of nutrition for the animal involved. Evidence of wood boring and leaf eating extends from the late Carboniferous onwards. It appears that 'continuous marginal' leaf-feeding preceded 'interrupted marginal' feeding, and that this was in turn followed by 'non-marginal' leaf feeding. The latter first appeared in Cretaceous angiosperms. Some diversity of leaf miners and leaf galls are also represented in Cretaceous angiosperm leaf fossils.