Cinnabar larvae feeding on ragwort. Credit: Callum McLellan
Young birds that eat insects with conspicuous warning colouration to advertise their toxicity to would-be predators quickly learn to avoid other prey that carry the same markings. Developing on this understanding, a University of Bristol team have shown for the very first time that birds don’t just learn the colours of dangerous prey, they can also learn the appearance of the plants such insects live on.
To do this, the scientists exposed artificial cinnabar caterpillars, characterised by bright yellow and black stripes, and non-signalling fake caterpillar targets to wild avian predation …