The wing length of Ringneck Parrots in the south-west of Western Australia has been increasing since the 1970s, coinciding with that region becoming hotter and drier. This is a possible rapid evolutionary response to changing climate.
‘We have measurements of these parrots going back to 1904, thanks to specimens collected by the Western Australian Museum,’ said Associate Professor Dylan Korczynskyj, from the University of Notre Dame Australia.
Worldwide, there have been many changes in species’ distribution and life cycles due to environmental changes. Now researchers are beginning to see changes in body sizes.
'As a general rule, Ringneck parrots gradually get larger the further south you head. But what we've discovered is that the wing length of the south-west parrots has increased by 4-5 mm over the past 45 years,’ said Associate Professor Korczynskyj.
‘The sub-species of Ringneck Parrots in the north and east of the state that haven’t experienced the same climate shifts don’t have these larger wings.’
‘There is the possibility that the birds’ wings are an evolutionary response to the hotter conditions, and help the parrots cool down.’
‘The change in these parrots fits with what biologists call ‘Allen’s rule’. That is, in warmer climates, appendages such as wings get larger to help shed unwanted heat. Our results are only preliminary, but we might be seeing evolution in action.’
‘Learning about the links between body size and environment will help us understand how animals are likely to respond to environment shifts such as climate change,’ said Associate Professor Korczynskyj.
The species name for the Australian Ringneck Parrots is Platycercus zonarius. The two sub-species are semitorquatus (south-west WA, and the subject of this research) and zonarius (north and eastern WA).
Associate Professor Korczynskyj presented his results today at the Ecological Society of Australia’s 2016 annual conference in Fremantle, Western Australia. The Ecological Society of Australia is the peak group of ecologists in Australia, with over 1500 members from all states and territories.
The Conference Program is available at: http://www.esa2016.org.au/