"a... native orchid trying to outwit a randy male wasp... Anne Gaskett, a PhD student from Macquarie University in Sydney... uses advanced colour technology... to understand how five species of native tongue orchids trick a male wasp into believing he has found a sexual partner.
She says the findings will help to develop environmentally sensitive pest controls and conserve orchid species. Ms Gaskett looked at the orchid dupe wasp (Lissopimpla excelsa). And she says as far as the male is concerned, tongue orchids have "curves in all the right places". But the wasp is fooled for only so long. Her research found that even after just a few exposures to the orchid the wasp avoids trying to have sex with it. Ms Gaskett from the Department of Biological Sciences says the orchid must then enhance its mimicry of the female wasp to continue to attract the male wasp and pollinate. "This means only the most persuasive orchids will continue to reproduce," she says. ... Orchids are the only plant whose flowers trick insects using such sexual deception. The aim is to convince the insect to 'mate' with them. The insect accidentally collects pollen on its body, which is then transported to another flower. Ms Gaskett says the orchid dupe wasp is attracted to and pollinates five species of tongue orchid in the genus Cryptostylis. This is unusual as normally one insect pollinates one species of orchid. She says this means the five orchid species, which look completely different to the human eye, must look and feel the same to the male wasp. ... Ms Gaskett used a spectrometer to analyse the colours of four of the five species and a female wasp. Taking into account factors including the background colour, ambient light and colour range of the male wasp's receptors, she found the orchid replicates almost exactly the colours of the female orchid dupe wasp. She has also found 'hidden shapes' that feel like a female wasp to the male, including 'love handles' the male wasp grip onto while mating. ... Ms Gaskett... is now studying the perfume of the orchids and testing them on wasp antennae to look at the role of smell in the seduction process." URL : http://abc.net.au/news/stories/2007/08/21/2010644.htm?section=australia *************** Regards, VB _______________________________________________ the OrchidGuide Digest (OGD) [email protected] http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
