Many studies have already shown that flowering times have come earlier as a result of recent global warming, but what's unknown is how long the plants will be able to "keep up" by budding earlier and earlier.
However, at low concentrations, caffeine appears to have a secondary advantage, attracting honeybees and enhancing their long-term memory, said lead author Geraldine Wright, a neuroscientist at Newcastle University in England, whose study was published online March 7 in the journal Science.
"We show that caffeine-a compound whose ecological role is mainly to deter and poison herbivores-actually acts like a drug in an ecologically relevant context," Wright said. "The plant is secretly drugging the pollinator. It may help the bee, but the plant cares more about having a pollinator with high fidelity!"
Wright's team wanted to investigate what effect caffeine could have on the learning and memory of honeybees, so they measured the caffeine content in two types of plants, Citrus and Coffea. Both have elaborate flowers and strong scents that attract honeybees. The plants benefit from bee pollination by producing more fruits and seeds. (Read more about learning and memory in honeybees.)
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