ABSTRACT
Plant-feeding insects and arthropods of the geological past Evidence shows that as soon as the first arthropods crawled out of the sea, they started to feed on any available plant, probably at that time mostly green and blue (Cyanophyta or Cyanobacteria) algae. Then, some primitive green plants evolved, but it seems that at the beginning, after the first chewing arthropods evolved, the sapsucking forms dominated in what was then the Paleozoic forest. (See Figure 2.1.)
2.1 The plant kingdom If we accept the findings of Stewart and Rothwell (1993), the first vascular plants appeared mid-Silurian, i.e., 435 million years ago. Green algae and cyanobacteria probably colonized swamps and shores of primeval seas even earlier, during the Ordovician period, i.e., early Silurian. It seems that the land plants are derived from progenitors that would be classified with mod em Charophyceae (Graham, 1993). According to Graham, the land-adapted plants arrived 450 to 470 million years ago (late Ordovician). The first vascu lar plant known is the Cooksonia sp. It seems even that the first flowering plant (Pannaulika Triassic) emerged from the Triassic mud 220 million years ago (Crane, 1993).
