My Husband & Other Animals

by Janaki Lenin

A lot of humans are addicted to caffeine but many more are addicted to tobacco. The nicotine found in the leaves is another powerful neurotoxic insecticide. Besides protecting themselves, the plants have another use for the drug. Their nectar is tainted with it, but they are not trying to poison their pollinators; that would be self-destructive. The plants want them to be brief and move on, and the nicotine discourages insects from drinking long and deep. So the pollinators have to visit more plants to get a full meal. In doing so, they traffic pollen among many plants increasing their genetic diversity. And the insects are apparently hooked to the nicotine. In experiments, they demonstrated their preference for caffeine or nicotine-tainted nectar to the plain, safe kind. But they like just enough for a buzz, not too much to paralyze them, not too little to be uninteresting.