Fluoro flirting
Want to attract the opposite sex? Then bring on the fluoro colours, according to an international study published recently in the international journal Science. A study conducted at UQ by British and Australian scientists has found budgerigars show a significant sexual preference for mates with fluorescent plumage.
"It's the first demonstrated use of fluorescence in the animal kingdom, apart from humans," said Dr Justin Marshall (pictured right) of UQ?s Vision Touch and Hearing Research Centre.
Dr Marshall is the study's co-author with Dr Kathryn Arnold of the University of Glasgow and Dr Ian Owens, formerly at UQ and now with Imperial College.
"For some time humans have used fluorescence as an attractant," he said. "We have fluorescent highlighters and Post-It notes and washing powders which give white fluorescence to our clothes. Some advertisers use fluorescent paints in their displays and there are now even fluorescent tattoos used by night-clubbers.
"We are currently interested in animal communication and how animals use colours to 'talk' to each other. An obvious choice is parrots, which are vibrantly coloured."
Dr Marshall said the researchers followed up an earlier Australian Museum study which sought an explanation for the fluorescence discovered in the feathers of stuffed parrots.
They conducted experiments among budgerigars with naturally occurring yellow fluorescent plumage on their crowns and cheeks for courtship displays.
Birds were given a choice of two stimulus birds of the opposite sex one retaining fluorescent plumage on their crown and the other whose fluorescence was reduced with sunblock. This decreased the amount of UV needed for excitation.
The researchers found strong evidence for fluorescent sexual signalling among the parrots. Focal birds showed a significant sexual preference for fluorescent stimulus birds of the opposite sex. The scientists calculated fluorescent plumage added 14 percent extra 'chromatic signal' to the crown region, as perceived by the visual system of another budgerigar.
They also found that neither male nor female birds showed a significant social preference for same-sex fluorescent plumage birds. "The bottom line for budgies, and possibly other parrots, is that success in mating only comes if you literally glow," Dr Marshall said.
Last year Dr Marshall won the L'Oreal Art & Science of Colour Prize of 30,000 Euros (~AUS$50,000) in Paris for his research on colour vision and colour communication in reef fish.
He said he hoped to pursue further studies of colour communication in the animal kingdom this year.
Research team
Associate Professor Justin Marshall Vision Touch and Hearing Research Centre) www.uq.edu.au/uqresearchers/researcher/marshallj.html;
Dr Ian Owens (University of London);
Dr Kate Arnold (now at the University of Glasgow).
Funding
Specific to project:1998 ARC small grant ($15,000); 1999 UQ internal grant ($25,000)
Part of research funding from following: 19982000 ARC large grant (Dr Marshall) ($176,000)
19962000 ARC QEII Fellowship (Dr Marshall) $70,000/yr
i.owens@ic.ac.uk
K.Arnold@bio.gla.ac.uk
j.marshall@vthrc.uq.edu.au
Web link
www.vrhrc.uq.edu.au/ecovis
