Mesozoic insect fossils reveal the early evolution of twig mimicry

Twig mimicry is common and diversified within Phasmatodea (stick and leaf insects). However, the fossil record of Phasmatodea is scant, especially evidence for the early evolution of twig mimicry. Herein, Yang et al. describe several stick insects from the Middle Jurassic (∼165 Ma) and mid-Cretaceous (∼99 Ma), and reconstruct the transitions in thoracic morphology relating to their overall twig form. Based on the phylogenetic relationships within Phasmatodea, the new findings suggest a possible evolutionary scenario for the phenomenon of twig mimicry.