“sleep sites of chameleons (family Chamaeleoni- dae) tend to be located on unstable perches, either narrow-substrate types while sleeping, as long as the sleep perch is rel- atively narrow and unstable.”…”The specialisation of sleeping on unstable perches could act as an ‘early warning system’ to detect approaching predators“…
http://www.anthonyherrel.fr/publications/Mohanty et al 2021 Biol Rev.pdf
http://www.anthonyherrel.fr/publications/Mohanty et al 2021 Biol Rev.pdf