Skip to Main Content

Critter Chemistry

June 7, 1999

Alluring Scent Entices Bees to Illusory Sex

Certain orchids seduce male pollinator bees by producing the same compounds (and in the same proportions) as those found in the female bees' sex pheromones. Mistaking the scent of Ophrys sphegodes orchids for the scent emitted by receptive females, male Andrena nigroaenea bees engage in "pseudocopulations" with the flowers, thus causing their pollination. Florian P. Schiestl, an evolutionary biologist at the University of Vienna's zoology institute, and collaborators have identified the components of the male bee attractant in orchids and in female bees using gas chromatography with electroantennographic detection, in which an antenna from a male bee acts as a detector [Nature, 399, 421 (1999)]. The active compounds are straight-chain hydrocarbons whose relative abundances in the female bees and orchids are very similar. These orchids seem to have evolved an economical way to ensure that they get pollinated: By using compounds originally needed to prevent water loss, they do not have to use resources to generate typical odorous natural products that other plants use to attract pollinators

Chemical & Engineering News
ISSN 0009-2347
Copyright © 2010 American Chemical Society