Nearly all orchids of the genus Ophrys are pollinated by means of sexual deception, mostly by bees (Superfamily Apoidea) and wasps (SF. Scolioidea, SF. Sphecoidea). Lured by the odour and insect-like shape of the flower, the pollinating male alights on the labellum and attempts to copulate with it. During these so-called "pseudocopulations", the male contacts the pollinia, which become attached to its head or abdomen. Flower’s odour is the most important cue for eliciting male mating behaviour.

In a comparative approach, we identify and compare the male-attracting odour compounds in female bees (wasps) and in Ophrys flowers. We conduct behavioural tests, quantitative chemical analyses, electroantennogram assays as well as combined gas chromatography and electroantennogram recordings of insect olfactory responses. Meanwhile we were able to show that virgin female bees and Ophrys flowers use the same compounds to trigger copulatory behaviour in the males. Therefore, we confirmed the hypothesis of chemical mimicry in Ophrys pollination.

Coworkers: Julia Gögler

Collaborations: Wittko Francke, Robert Twele (both University of Hamburg), Nicolas J. Vereecken (Free University of Brussels), Joachim Ruther (Free University of Berlin)

Funding: DFG Priority Programme 1127 “Radiationen – Genese Biologischer Vielfalt”