Although katydids can camouflage themselves onto the leaves that they reside on, one of the most impressive things they can do is acoustic signaling. Many insects can blend into the leaves they live on, but the katydids are some of the only insects with a very complex form of acoustic signaling. In fact, “insects like katydids have evolved biophysical mechanisms for auditory processing that are remarkably equivalent to those of mammals” (Montealegre-z, 2015). This impressive feature is shared among all katydid species, therefore I will be discussing this feature in terms of all the katydid species.

When the katydids first receive a signal, it can affect one of three sound inputs: the acoustic spiracle or the two tympanal membranes on the forelegs which act like ears. It is then received by the crista acustica which are the sound reception cells. The cells then send the received signals to the insect’s ganglia (Mugleston, 2013 & Montealegre-z, 2015).

The general anatomy of the Katydid ear including the acoustic spiracle and the two tympanal membranes (PTM and ATM).

These organisms use this complex way of receiving and sending auditory signals for not only sexual selection, but also territorial displays and sometimes to attract prey (Mugleston, 2013). Using the knowledge about this physiological feature, you could learn how these insects can differentiate between auditory signaling that are directed towards them and are not directed towards them.

References:

Mugleston, J. D., Song, H., & Whiting, M. F. (2013). A century of paraphyly: A molecular phylogeny of katydids (Orthoptera: Tettigoniidae) supports multiple origins of leaf-like wings. Molecular Phylogenetics and Evolution, 69(3), 1120-1134.

Montealegre-z, F., & Robert, D. (2015). Biomechanics of hearing in katydids. Journal of Comparative Physiology A, 201(1), 5-18.