Many plants produce caffeine. The bitter compound in their leaves is thought to repel herbivores, but that does not explain why is found in the nectar of plants. The answer could lie in pollinators.
Just like students having coffee while cramming for exams, honey bees seem to learn better and have improved memory when consuming caffeinated nectar. The downside is that bees seem to overestimate the quality of caffeinated nectar. The plants benefit from this relationship but the bees may suffer in the end. “Caffeine-enhanced foraging may reduce honey storage” because the bees go for the buzz—they focus on the plants with caffeinated nectar rather than other flowers with higher quality nectar.
Source: Caffeinated Forage Tricks Honeybees into Increasing Foraging and Recruitment Behaviors. M. Couvillon et al. Current Biology. 2015. Vol 25. pp. 1–4.
- Janet Wallace