An insect trap adjusting to weather conditions: Nepenthes rafflesiana plants control the fluid level in their pitchers to maximise prey capture.

Acknowledgements: We would like to thank Universiti Brunei Darussalam for providing logistical support throughout field seasons in 2023 and 2024. We are grateful to the Brunei Forestry Department for issuing our forest entry and collection permits. Additional thanks go to Lorenz Mammen, Ritabrata Chowdhury and Isaac Howell for their assistance during field data collection and to the Engin, Tinggal and Rahaman families for their hospitality and support during our time in Brunei.