Some plants lure bees by spiking nectar with caffeine

Some plants offer top-shelf nectar, but they face stiff competition when it comes to getting bees' attention. Researchers have found that some plants are spiking their own nectar with caffeine because, as it turns out, bees love to get wired. Once bees get hooked on the caffeinated nectar, they begin to prefer it over equal or better quality non-caffeinated nectar, getting extra picky over what flowers they choose to visit.

The information comes from a report published today in Current Biology that details the caffeinated preferences of honey bees. Many types of plants that produce flowers have low amounts of caffeine in the nectar; research replicated this using a sucrose mix with and without caffeine.

Bees that consumed the caffeinated solution responded to the drugging with increased foraging, and by getting friends to forage from the same caffeinated plants. Bees encourage other bees to forage from a particular plant with a type of dance; with caffeine present, bees' dancing quadrupled in relation to that of non-caffeinated bees.

Honey bees aren't satisfied with just a sip or two, either. The researchers found that the bees who consumed caffeinated nectar would most often return to the location to get more, even if there was none of the solution left to partake from. On the downside, the bees didn't seem as keen on going out and looking elsewhere — even if the pots were empty, so to speak.

The big question now is whether plants with caffeine also have less sweet nectar, something that could affect honey production by causing bees to gravitate toward inferior sources.