Angela Moles (pictured) has found
that 92 per cent of vines are left-
handed.

Lisa Simpson was wrong about the Coriolis effect altering the direction that water goes down the drain, and research has found it doesn't affect plants either.

Australian researchers have found that 92 per cent of vines twist anti-clockwise—regardless of their location north or south of the equator.

The work, announced 26 August 2008 at the L’Oréal For Women in Science Fellowship ceremony in Melbourne, is a small part of a vast body of work to understand how plants around the world vary and adapt to climate.

2008 L'Oréal Fellow Angela Moles visited 75 study sites in two years. At each site—in Zambia, China, Peru, Israel, Patagonia, Alaska, Congo, Australia and elsewhere—she and her international team of scientists observed and measured everything they could.

Now Angela and her colleagues are mining the information they collected. Their discovery of ‘left-handed’ plants is one of the first results – published with her colleague Will Edwards from James Cook University.

“We tested three hypotheses,” says Angela, an evolutionary biologist at The University of New South Wales.

 “1) that plant twining direction is random; 2) that twining direction is determined by plant tips following the apparent movement of the sun across the sky; and 3) that twining direction is determined by the Coriolis effect.”

This is the effect that Lisa Simpson thought made water go down the drain in different directions north and south of the equator.

“We found no difference in the proportion of stems twining clockwise vs anticlockwise between the northern and southern hemispheres. In fact, 92 per cent of the stems we recorded twined in an anticlockwise direction.”

“We rejected all three of our theories. We are now investigating the possibility that the widespread phenomenon of anticlockwise twining arises as a function of the left-handed bias of all biological molecules on earth.”

Interestingly, about 94 per cent of spiral sea shells spiral in the same direction, and 90-93 per cent of people are right-handed.

Angela says the study illustrates just how little we actually know about the world in which we live. In an earlier study she compiled information on 12,669 plant species. She discovered that plant seeds in the tropics are, on average, 300 times bigger than seeds in colder places like the northern coniferous forests.

In the long term, Angela hopes that her ideas will lead to the development of sophisticated software that can predict larger ecological questions. It could for example predict the impact of climate change on Sydney. It could also warn which plants are likely to become weeds in a particular ecosystem.

The study The global trend in plant twining direction was published in Global Ecology and Biogeography (2007)16, 795–800.

Angela was one of four recipients of the $20,000 L’Oréal Australia For Women in Science Fellowships for 2008, presented by David de Kretser, Governor of Victoria, and Mark Tucker, CEO of L’Oréal Australia, at a ceremony on 26 August 2008.