University of Adelaide researchers have discovered that recent climate change is causing leaves of some Australian plants to narrow in size.

The study, which is the first of its kind in the world, highlights that plant species are already responding to changes in climate. The results are published online today in the Royal Society journal Biology Letters.

Researchers analysed leaves from herbarium specimens of Narrow-leaf Hopbush (Dodonaea viscosa subsp. angustissima) dating from the 1880s to the present. The study focused on specimens from South Australia’s Flinders Ranges.

The analysis revealed a 2mm decrease in leaf width (within a total range of 1-9mm) over 127 years across the region. Between 1950 and 2005, there has been a 1.2ºC increase in maximum temperatures in South Australia but little change in rainfall in the Flinders Ranges.

‘Climate change is often discussed in terms of future impacts, but changes in temperature over recent decades have already been ecologically significant,