New research shows a previously unrecognised adaptation to changing climatic conditions in one of the most charismatic plant genera of South-East Asia, the carnivorous pitcher plant.
Published in the March 2026 edition of the Annals of Botany, the research was led by Charlotte Andrew, a PhD student in our Insect Biomechanics Group.
Nepenthes rafflesiana, the carnivorous pitcher plant, has leaves that form cup-like pitchers. These are are partially filled with a sticky fluid to capture insect prey for nutritional gain. Insects fall from the slippery pitcher rim and land in the fluid which traps and digests them.
High or low fluid levels make it easier for insects to escape, so by maintaining an intermediate fluid level within their pitchers these plants maximise their capture of insect prey.
Researchers investigated how this pitcher fluid is affected by weather conditions and how these plants cope with environmental challenges.
They found that pitchers maintain an intermediate fluid level by controlling both the fluid's volume and concentration; removing fluid when it becomes too diluted during rainfall and secreting fluid to top it up when it evaporates during hot weather.
This active control is a previously unrecognized pitcher plant adaptation to their exposed habitats; understanding it is important for predicting the ability of these plants to withstand extreme weather conditions enhanced by climate change.
Charlotte’s Research Story
Charlotte's background in bioengineering led to her current research focus, “I have always been interested in the mechanics of the world around us.
“From my early research on the use of stick insect adhesive footpad secretions in biomedical applications, I have been truly fascinated by the weird and wonderful fluids that many species employ for important functions. This led me to my present research where I study how carnivorous plants use fluids to maximise the amount of insect prey they can capture.”
This research is funded through the Whitten Studentship for Aquatic Biology.
Read the paper: C N S Andrew, J Y Bu, N S Kelly, S Johnson, F Metali, T U Grafe, U Bauer, W Federle, An insect trap adjusting to weather conditions: Nepenthes rafflesiana plants control the fluid level in their pitchers to maximize prey capture, Annals of Botany, 2025;, mcaf294, https://doi.org/10.1093/aob/mcaf294