How a bee finds its first buttercup.

A bee that specializes in visiting buttercups relies oil a just-for-newbies scent to help with its first attempts at flower identification.

European bees collected in the wild but raised in the laboratory away from real flowers get so excited by whiffs of a volatile compound from buttercups that they try to burrow through cheesecloth scented with the substance, reports Heidi E.M. Dobson of Whitman College in Walla Walla, Washington. Once the bees have some experience buzzing around buttercups, however, they no longer show a strong preference for the scent. "Seemingly, they've changed their search image," Dobson says. Learning a suite of other cues could make identification faster, she speculates.

Dobson has wondered for years how these specialized bees nail the right flowers. Their parents aren't around to provide taxonomy tips. Her earlier tests found that lab bees prefer the color yellow but come across many different yellow flowers.

Buttercup pollen releases bigger whiffs of the compound she tested than the rest of the flower does. The lab bees preferred buttercup pollen to offerings from other spring flowers.

Dobson has never tested the compound with cows, but she says it reportedly gives them taxonomy tips too, signaling a plant not worth munching.