Fig. 2. (A–T) Representative continuous, cyclic or discontinuous gas exchange patterns for all of the species and orders investigated in this study. Zehntneria mystica (Phasmatodea, Phasmatidae) (L) is not discussed in the text. However, a single specimen showed a clear cyclic trace, therefore the graph is included. The other phasmid, Extatosoma tiaratum (K), is a leaf-mimicking species that shows a swaying response to the slightest air flow, which explains the limited evidence for cyclic gas exchange in this species.