Bees 311 Phil Hawkins/Bloomberg.
(photo credit: Phil Hawkins/Bloomberg)
A recent University of Haifa study has found that bees prefer nectar with a small concentration of caffeine and nicotine to nectar without.
“This could be an evolutionary trait intended to make the bee addicted,” said Prof. Ido Yitzchaki, who headed the study.
The research, conducted at the university’s biology department in Oranim, showed that bees clearly prefer nectar containing nicotine and caffeine over the “clean” nectar. The preferred nicotine concentration was 1 milligram per liter, similar to that found in nature. But, as opposed to humans, the bees do not seem likely to overdose, as the study found that the bees reject nectar containing higher levels of nicotine.
“The purpose of nectar, among other aspects of the flower,” said Yitzchaki, “is to attract insects, which subsequently disseminate the flower’s pollen, ultimately enabling the flower to reproduce”. This is also the reason for flowers’ bright colors and scented aroma, he says.
Scientists, however, began to discover traces of toxins in flowers’ nectar, such as caffeine and nicotine, the latter lethal in high enough doses.
So if evolution is at work, why would flowers have toxins in their alluring potion? The answer, Yitzchaki discovered, is that these toxins attract bees, just as they do humans. But this is not to say that bees become addicted like humans do. To prove addiction, other factors, such as ever-increasing consumption, and withdrawal symptoms need to be present, qualities difficult to examine in bees.
According to the researchers, it is not yet clear whether the addictive
substances in the nectar became present in an evolutionary process in
order to make pollination more efficient. However, it can be assumed,
they say, that the plants that survived natural selection are those
that developed “correct” levels of these addictive substances, enabling
them to attract bees, thus giving them a significant advantage over
Yitzchaki hopes to conduct future stages of this study to determine
whether or not the bees truly are addicted, or just have a sweet tooth
for caffeine and nicotine.