Meganeura sp. insect fossil. Meganeura were about three times the size of the largest flying insects today, with wingspans exceeding 65??1 centimetres. They resembled and are related to the present-day dragonflies and were predatory, with their diet mainly consisting of other insects. Their evolution has been tied to the absence of other aerial predators coupled with the much higher oxygen content of the atmosphere at this time, which may have facilitated breathing and flight. This fossil dates to the Upper Carboniferous Age, 290 million years ago. Found in Herault, France.