Beer-flavoring compounds guide insects
By Susan Milius
The compounds that give beer some bitter flavor notes also show up in garden flowers–but with more sober jobs.
Chemical ecologist Thomas Eisner of Cornell University found some of the bitter beer compounds, called DIPs for dearomatized isoprenylated phloroglucinols, in flowers of six species of the genus Hypericum. To bees’ ultraviolet-sensing eyes, the compounds create dark markings on the blooms. Scientists already knew that pigments, called flavonoids, created bee-visible markings on flowers, but the DIPs came as a surprise.