Behaviour 2019
Beyond looking like a stick: phasmid behavioural crypsis strategies
Eunice Tan1, Sebastian Pohl1, Y Norma-Rashid2, Rodzay Wahab3, Haaken Bungam1. 1Yale-NUS College, Singapore, Singapore, Singapore; 2University of Malaya, Kuala Lumpur, Pahang, Malaysia; 3Universiti Brunei Darussalam, Brunei, Brunei, Brunei

Behavioural crypsis, where an animal adopts a particular behaviour to avoid detection, is an anti-predator strategy that is understudied. Animals may adopt different forms of behavioural crypsis, and its optimal form may differ depending on an animal’s colour patterns and morphology. Phasmids are conventionally known to resemble parts of plants. However, this resemblance may vary across life stages and species, and a broad range of colourful phenotypes exists as well. Our study utilises two species of phasmids with varying morphology and colour patterns, to examine their behavioural responses at different ontogenetic stages to a wind stimulus. We found that phasmids respond differently across species and to a certain extent, across life stages. The adults of both species adopt largely species-specific behaviours, while the nymphs adopt a variety of behaviours depending on their species and age. Our results highlight the importance of considering different life stages in behavioural studies and provides a novel investigation into the role of colour patterns and behavioural crypsis in the signalling strategies of phasmids.