A new discovery is challenging a theory that is almost half a century old, could explain why the south-west of WA is one of the world's biodiversity hotspots, and could help to preserve exquisitely adapted plants and animals.
The University of Western Australia's Dr Siegy Krauss and colleagues at Kings Park and Botanic Garden recently analysed the seeds of a Banksia pollinated by honeyeaters. They found, to their surprise, that the paternity of the seeds proved that the birds had flown hundreds of metres from banksia to banksia rather than always visiting the closest tree.
This finding confirmed pioneering discoveries of similar pollinator movements on eucalypts by Winthrop Professor Steve Hopper - who was Director of the UK's Royal Botanic Gardens at Kew for six years and is now based at UWA's Albany Centre. Their joint findings are so significant that they received almost $1 million from the Australian Research Council to test the conservation and evolutionary consequences of such promiscuous plant matings in southwest Australia.
The discovery - which was only possible through new techniques of molecular analysis - contests ‘optimal foraging theory' which was posited in 1966 and suggests that organisms conserve energy by eating food closest to them. (In moving from plant to plant to feed, some insects, birds and mammals inadvertently pollinate the plants they visit.)
It also offers a good reason why the small isolated pockets of highly diverse flora in the south-west show few signs of inbreeding, with big numbers of pollinators such as honey-eaters, lorikeets, silver-eyes, honey possums and pygmy possums enabling far-reaching pollen dispersal.
But while Professor Hopper and his colleagues are excited about modern science, they are also increasingly collaborating with Noongar elders in the south-west to better understand through an ancient knowledge-system how "one of the richest cultures on the planet" interacts with the landscape.
"The Noongars can tell us a lot about our responsibility for the place in which we live if we want it to care for us," he said. "While we hope that novel biological discoveries will attract young scientists to the south-west, we also want to offer students another world-view and are proud of our foundation unit, ‘Knowing Country: The Dreaming and Darwin', run jointly with the School of Indigenous Studies"
Professor Hopper said he was excited to be back in Australia - and particularly the south-west - after having lived in the "young, postglacial landscape" of the UK.
Dieback and bulldozers threaten this precious Southwest Australian Global Biodiversity Hotspot, he said, but he hopes that the more people know about the unique interactions between its plants and animals, the more they will strive to preserve it.
Winthrop Professor Steve Hopper (UWA Centre of Excellence in Natural Resource Management and School of Plant Biology) (+61 8) 9842 0842
David Stacey (UWA Public Affairs) (+61 8) 6488 3229 / (+61 4) 32 637 716