London: It seems honeybees too get their buzz from caffeine just as humans do!
Scientists have shown that caffeine improves a honeybee`s memory and could help plants recruit more bees to spread their pollen.
The study published in Science, has shown that in tests honeybees feeding on a sugar solution containing caffeine, which occurs naturally in the nectar of coffee and citrus flowers, were three times more likely to remember a flower`s scent than those feeding on just sugar.
"Bees that have fed on caffeine-laced nectar are laden with coffee pollen and these bees search for other coffee plants to find more nectar, leading to better pollination," study leader Dr Geraldine Wright, from Newcastle University, said, adding the effect of caffeine benefits both the honeybee and the plant.
"So, caffeine in nectar is likely to improve the bee`s foraging prowess while providing the plant with a more faithful pollinator," Wright said in a statement.
Researchers found that the nectar of Citrus and Coffea species often contained low doses of caffeine. They included `robusta` coffee species mainly used to produce freeze-dried coffee and `arabica` used for espresso and filter coffee.
"Caffeine is a defence chemical in plants and tastes bitter to many insects including bees so we were surprised to find it in the nectar. However, it occurs at a dose that`s too low for the bees to taste but high enough to affect bee behaviour," Co-author Professor Phil Stevenson the University of Greenwich`s Natural Resources Institute said.
The effect of caffeine on the bees` long-term memory was profound with three times as many bees remembering the floral scent 24 hours later and twice as many bees remembering the scent after three days.
Typically, the nectar in the flower of a coffee plant contains almost as much caffeine as a cup of instant coffee.
"This work helps us understand the basic mechanisms of how caffeine affects our brains. What we see in bees could explain why people prefer to drink coffee when studying," Wright added.
"Although human and honeybee brains obviously have lots of differences, when you look at the level of cells, proteins and genes, human and bee brains function very similarly. Thus, we can use the honeybee to investigate how caffeine affects our own brains and behaviours," Dr Julie Mustard from Arizona State University, said.