Chapter 11 INSECTS AND PLANTS Insects and plants share ancient associations that date from the Carboniferous, some 300 million years ago (Fig. ). Evidence preserved in fossilized plant parts of insect damage indicates a diversity of types of phytophagy (plant-feeding) by insects. | TIC11 5 20 04 4 42 PM Page 263 Chapter 11 INSECTS AND PLANTS Specialized plant-associated neotropical insects. After various sources. TIC11 5 20 04 4 42 PM Page 264 264 Insects and plants Insects and plants share ancient associations that date from the Carboniferous some 300 million years ago Fig. . Evidence preserved in fossilized plant parts of insect damage indicates a diversity of types of phytophagy plant-feeding by insects which are presumed to have had different mouthparts and associated with tree and seed ferns from Late Carboniferous coal deposits. Prior to the origin of the now dominant angiosperms flowering plants the diversification of other seed-plants namely conifers seed ferns cycads and extinct bennettiales provided the template for radiation of insects with specific plant-feeding associations. Some of these such as weevils and thrips with cycads persist to this day. However the major diversification of insects became manifest later in the Cretaceous period. At this time angiosperms dramatically increased in diversity in a radiation that displaced the previously dominant plant groups of the Jurassic period. Interpreting the early evolution of the angiosperms is contentious partly because of the paucity of fossilized flowers prior to the period of radiation and also because of the apparent rapidity of the origin and diversification within the major angiosperm families. However according to estimates of their phylogeny the earliest angiosperms may have been insect-pollinated perhaps by beetles. Many living representatives of primitive families of beetles feed on fungi fern spores or pollen of other non-angiosperm taxa such as cycads. As this feeding type preceded the angiosperm radiation it can be seen as a preadaptation for angiosperm pollination. The ability of flying insects to transport pollen from flower to flower on different plants is fundamental to cross-pollination. Other than the beetles the most significant and diverse present-day .
