New research says that plants add addictive ingredients to their nectar to keep bees coming back for more.

Scientists at Newcastle University in the UK found that plants add addictive drugs like caffeine to lure the bees back to pollinate.

The New York Times reported that plants use numerous methods to attract pollinators including, scents, chemicals and other substances that bees love and predators hate.

The study saw researchers train bees to associate sweet rewards with a certain scent.

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Researchers were trying to understand whether the bees would treat plants with caffeinated nectar the same way as those with just sugary nectar.

It turns out that the bees love caffeine.

NPR reported that bees feeding on the caffeinated nectar were three times more likely to return to a flower than the one with sugar.

Researchers realized that caffeine helped spark memory in the bees and may have made them addicted to the plant.

Bees have very different brains from people but they do have receptors for the neurotransmitter adenosine to which caffeine binds, reported the New Scientist.

The study could help shed light on what caffeine does to the human brain as well.

The findings were published in the journal Science.