As anyone who has ended up all jittery after abusing the free Rockstars at O-Week can tell you, too much caffeine is toxic. Normally plants have caffeine in their leaves and seeds as a way to paralyse and/or kill parasitic insects. However scientists have also discovered low levels of caffeine in the nectar of some flowers.
In case memorizing your timetable for this semester has led you to delete high school biology from your memory bank, here’s a quick refresher. Nectar is a sweet juice that flowers make to attract insects carrying pollen, which is the way they fertilise each other. This is why the discovery of caffeine in nectar is so puzzling: why would plants poison their helpful little sex surrogates?
Scientists believe the levels of caffeine in nectar are low enough to only be giving the bees a bit of a buzz (sorry). The researchers gave bees a mixture of sugar with a particular floral scent, with or without caffeine. They then tested how well the bees could remember the smell in the mixture. They found that the bees jacked up on nature’s Red Bull were much better at recalling the scent than those who weren’t. The advantage to the flowers is that the better bees are at remembering where to find them, the better their chances of getting some pollen all up in dat.
The same scientists also conducted an experiment on how bees feel about the taste of caffeine. They found that plants have evolved over millions of years to brew the caffeine hit into irresistible deliciousness. Like most humans, bees find drinks with too much caffeine bitter and won’t drink them. The research found that nectar had caffeine at doses high enough to give the bees a bit of a kick, but still kept it as tasty as possible. Kind of like what Campos does.