Orchids Trick Wasps into Sex

1st\NW Quadrant: The Approval Matrix

By Ewen Callaway\New Scientist

WHILE few can resist the allure of a beautiful orchid, some wasps outdo the most ardent flower lover. Male orchid dupe wasps become so enamoured with Australian tongue orchids, which give off the scent of female wasps, that they ejaculate. But what price does the wasp pay for this misdirected mating?

Many insects are sexually deceived into liaisons with flowers, but few go as far as Lissopimpla excelsa, says Anne Gaskett of Macquarie University in Sydney, Australia, who led the study (The American Naturalist, DOI: 10.1086/587532) testing the wasp's behaviour towards Cryptostylis.

Gaskett noticed that some wasps in the bush outside Sydney left a visible blob on tongue orchid flowers following their visits. "We decided to check if they were wasting their sperm on the flowers," she says, which closer examination confirmed.

Field experiments also showed nearly three-quarters of the male wasps ejaculated on the flowers...