Worms without eyes shouldn’t see colour — yet C. elegans can. In this episode, we dive into a landmark study that shows how worms use blue-to-amber light ratios to make foraging decisions. When exposed to toxic blue pigments like pyocyanin, worms avoid them — but only under white light. The twist? They do it all without opsins.
We explore:
How worms detect and avoid blue-pigment-secreting P. aeruginosa
Why light potentiates avoidance, but only for certain spectral ratios
How lite-1 and GUR-3 receptors mediate spectral sensitivity
Natural variation in colour preference across wild strains
The discovery that stress-related genes jkk-1 and lec-3 underlie colour-guided behaviour
This episode uncovers a new form of opsin-free colour vision, expanding our understanding of how simple organisms read complex environments.
📖 Based on the research article:
“C. elegans discriminates colors to guide foraging”
Dipon Ghosh, Dongyeop Lee, Xin Jin, H. Robert Horvitz & Michael N. Nitabach
Published in Science (2021)
🔗 https://doi.org/10.1126/science.abd3010
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