Partnership between bees and flowers: Fine-tuned feeding speed and nectar sugar concentration facilitate energy rewards and pollination service

Abstract

The interaction between bee pollinators and flowering plants lays the foundation of biodiversity and food production for human livelihoods, with three out of four crops worldwide relying on this interaction. The ongoing success of this mutualism is pow-ered by the bilateral and potentially dueling demands of food procurement for polli-nators and sexual reproduction for plants. However, the underlying mechanisms of the mutualism, which must simultaneously fulfil the requirements from both sides, remain unexplored. Here we establish a biomechanical framework that combines la-boratory tests and mathematical models to investigate the relationship between bees and plants, using the feeding speed of bees and the nectar sugar concentration of flowers as the core factors. We find that both the optimal frequency of a bee dipping nectar and the nectar sugar concentration are delicately balanced over narrow ranges to simultaneously satisfy demands of both parties of the mutualism. Human activities and climate change can perturb this balanced interaction, which would be detri-mental to this critical pollination system essential to staple crops around the world.