Palaeontology: Ancient wing sheds light on insect communication origins

The discovery of a fossilized insect wing, the features of which provide the earliest evidence so far of wing-based communication in insects, is reported this week in Communications Biology. The finding suggests that insects may have been using their wings to broadcast information since the Late Carboniferous period (approximately 310 million years ago).

Many insects use wing shape, colour or sound, to attract mates or deter predators. How and when these behaviours evolved has been uncertain because structures used for communication are difficult to distinguish from those used for other purposes in fossilized wings.

André Nel and colleagues discovered a fossilized insect wing in Liévin, France, belonging to a previously unidentified species of giant predatory grasshopper-like insect — Titanoptera — the largest of which had wingspans in excess of 33 centimeters. The authors have named the new species Theiatitan azari in reference to Theia, the Greek Titan goddess of light. The wing predates both the previously oldest known Titanoptera, and the remains of Permostridulus brongniarti, an insect that is thought to have used its wings to produce sound, by approximately 50 million years. The researchers identified multiple panels of varied angles and shapes within the forewings of some Titanoptera, including in T. azari, which are similar to those of other fossilized and modern insects that use their wings to reflect light or generate sound for communication. The shape and structure of the wing suggests that these panels may have allowed T. azari to communicate by using its wings to reflect light or produce crackling noises.

The findings, which highlight the importance of wings in insect communication throughout their evolutionary history, make T. azari the oldest known insect species to date to have used its wings for communication.