Flowers use adjustable ‘paint by numbers’ petal designs to attract pollinators
Flowers like hibiscus use an invisible blueprint established very early in petal formation that dictates the size of their bullseyes – a crucial pre-pattern that can significantly impact their ability to attract pollinating bees.
The study, by researchers at the Sainsbury Laboratory, University of Cambridge, also found that bees prefer larger bullseyes over smaller ones and fly 25% faster between artificial flower discs with larger bullseyes – potentially boosting efficiency for both bees and blossoms.
Patterns on the flowers of plants guide insects, like bees, to the centre of the flower, where nectar and pollen await, enhancing the plant’s chances of successful pollination. Despite their importance, surprisingly little is known about how these petal patterns form and how they have evolved into the vast diversity we see today, including spots, stripes, veins, and bullseyes.
The lead author on this paper is Dr Lucie Riglet, who is a research associate in Dr Edwige Moyroud‘s research group at the Sainsbury Laboratory, University of Cambridge. Professor Henrik Jönsson and Dr Argyris Zardilis, also from the Sainsbury Laboratory, and members of our Computational Morphodynamics Group were co-authors.
Image caption: Dr Lucie Riglet developed a quantitative imaging pipeline and deciphered the mechanisms specifying the distinct bullseye regions in developing petals of Hibiscus trionum combining imaging, genetics, computational modelling and bumblebee behaviour assays. (A) Hibiscus trionum petals with a boundary at the one-third position separating the purple proximal region and white distal domain. (B) At early developmental stages, when the petal is still greenish, lacking of any differentiation sign, a pre-pattern is already specifying the boundary region of the petal at maturity. (C) The Moyroud team identified the mechanisms behind pattern variations, using Hibiscus richardsonii, a sister species. (D) To investigate if bullseye proportion was able to be detected they tested bumblebees with artificial flowers mimicking H. trionum (medium) and H. richardsonii (small) bullseye sizes, and found that bumblebees preferred the medium-sized bullseye. Image credits: Lucie Riglet.