Evolution of insects

Having appeared more than 350 million years ago, when large plants began to populate the Earth, Insects probably developed from marine Myriapods. The earliest Insects that have come down to us as fossils date from the Carboniferous Period of the Palaeozoic Era, about 300 million years ago, and are winged forms; some of these primitive Insects, such as cockroaches, have kept their original forms down to the present day. Naturally, a great many of the species of that time have become extinct: they either disappeared completely or underwent evolution and transformation into different forms.

In the Triassic Period, about 230 million years ago, Diptera and Coleoptera appeared, while Lepidoptera and Neuroptera followed in the Cretaceous Period, about 140 million years ago; it is only later, during the Cenozoic Era, that the world of Insects, helped also by the spread of flowering plants, reached its full development, reaching and colonising the most varied environments.

Among the most striking and fantastic creatures we may mention the gigantic “Dragonflies” of the genus Meganeura which, with a wingspan of almost a metre, lived and flew in the forests of the Carboniferous Period. Many fossil Insects have come down to us embedded in the gummy resin, amber, that oozed from the trunks of conifers during the Mesozoic (Cretaceous) and Cenozoic Eras; many of these Insects have been perfectly preserved, and some have shapes and sizes similar to present-day ones.