South African Beetle Daisy, Gorteria diffusa, has long captivated scientists with its unique petal structure that resembles a female fly, enticing male flies to pollinate the plant. A recent study by Roman Kellenberger and colleagues, published in Current Biology, reveals the fascinating mechanism behind this three-dimensional deception, which repurposes existing genes to create a highly convincing imitation.

Researchers discovered three sets of genes in the daisy’s petals responsible for constructing the faux fly, all of which already serve other functions within the plant. The first set manages iron distribution, the second promotes root hair growth, and the third regulates flower production. The daisy achieves its remarkable deception by utilizing these gene sets in novel ways.

An orange daisy with a close-up of a male fly with a scatter of pollen over his body. Left is what might look like a lady fly, but is actually a modified petal.
A real fly (right) lands on a daisy petal next to the fake fly (left). Image: Roman Kellenberger/ University of Cambridge

The iron-moving genes alter the petal’s pigmentation, transforming the natural reddish-purple hue to a more fly-like blue-green. Root hair genes cause hairs on the petal to expand, creating texture, while the third gene set ensures the fake flies appear in random positions on the petals.

“This daisy didn’t evolve a new ‘make a fly’ gene. Instead it did something even cleverer – it brought together existing genes, which already do other things in different parts of the plant, to make a complicated spot on the petals that deceives male flies,” said Professor Beverley Glover, senior author of the study, in a press release.