An international team of researchers has developed new computer software to unlock the geometric secrets of leaves.
Assistant Professor Chuck Price, of The University of Western Australia, joined fellow US researchers to measure more than four million individual leaf veins from images of hundreds of plant species stored in the US.
Assistant Professor Price led the creation of software - called ‘LEAF GUI' - which was used to analyse the images. They showed that vein networks are organised into honeycomb-like units that allow water, carbon and nutrients to be distributed throughout leaves and between leaves and stems.
"These findings are important to understand how to distribute resources within a network in an efficient and robust fashion, all of which leaves do," Assistant Professor Price said.
In leaves, veins carry fluids necessary to grow and maintain photosynthesis. The researchers found that the honeycomb pattern had evolved to manage these tasks and was consistent across species no matter how big or small the leaf. Moreover, the average size of the honeycomb didn't change systematically across leaves of different size.
"Leaf networks are hierarchical much in the same way that single lane roads have minimal traffic while multi-lane highways carry many more cars," Assistant Professor Price said.
The researchers studied leaves from more than 13,000 individual specimens in the National Cleared Leaf Collection at the Museum of Natural History in the US Smithsonian Institution.
The work is also important because understanding how leaves grow and partition resources is vital for applications from agriculture to conservation. By better understanding how plants transport carbon, nitrogen and phosphorous - the raw materials of photosynthesis - it is likely that biologists will be able to better predict how plants will grow and adapt under different conditions, including climate change.
Assistant Professor Price's findings, in collaboration with colleagues Scott Wing, from the Smithsonian Institution in Washington DC, and Joshua Weitz, from the Georgia Institute of Technology in Atlanta, were published in the prestigious journal Ecology Letters.