By Susan Milius
In an extreme case of sex fakery, an orchid produces oddball chemicals that mimic a female wasp’s allure so well that males prefer the floral scents to the real thing, scientists say. This plant’s come-on is different from that of a related orchid that flirts with bees.
The Mediterranean orchid Ophrys speculum manufactures whiffs of the same scent that the female wasp Campsoscolia ciliata does. The flower misleads male wasps into mating attempts that benefit the plant by spreading pollen, explains Manfred Ayasse of the University of Ulm in Germany. He and his colleagues have now identified the attractants as chemicals not previously known in plants. The orchids produce them more abundantly than female wasps do, and males prefer the stronger bouquet, the researchers say in an upcoming Proceedings of the Royal Society of London B.