Australia's koalas cope with extreme heat by resting against cooler tree trunks, new research has revealed.
Thermal imaging uncovered the koalas' cool plan, confirming that they choose to hug trees that can be more than 5°C cooler than the air during hot weather.
Researchers observed the behaviour of 30 koalas during hot weather at French Island, Victoria. Co-author Andrew Krockenberger from James Cook University in Cairns, in far north-east Australia, says heat wave events can hit koala populations hard.
"We know that about a quarter of the koalas in one population in New South Wales died during a heat wave in 2009," Professor Krockenberger said.
"Understanding the types of factors that can make some populations more resilient is important." Koalas also pant and lick their fur to cool down, but that can lead to dehydration.
"Access to these trees can save about half the water a koala would need to keep cool on a hot day," lead researcher Dr Natalie Briscoe, from the University of Melbourne, said.
"Access to cool tree trunks would significantly reduce the amount of heat stress for koalas." Co-author Dr Michael Kearney said the findings were important as climate change is bringing about more extreme weather.
Researchers used a portable weather station on a long pole to measure what the koalas were experiencing in the places they chose to sit, compared to other places available to them.
"When we took the heat imagery it dramatically confirmed our idea that 'tree hugging' was an important cooling behaviour in extreme heat," Dr Michael Kearney said.
"Cool tree trunks are likely to be an important microhabitat during hot weather for other tree dwelling species including primates, leopards, birds and invertebrates.
"The availability of cooler trees should be considered when assessing habitat suitability under current and future climate scenarios."
Professor Krockenberger's research includes some of Australia's warmest koalas – the population on Magnetic Island, in the country's tropical northeast.
"These findings underscore the importance of trees to koalas especially, in the context of climate extremes," he said.
"In this study the coolest trees were acacias. They're not a koala food tree, but clearly they can be important when it comes to coping with the heat."
The study is published in the current edition of Biology Letters.
Linden Woodward | Eurek Alert!
Scientists uncover the role of a protein in production & survival of myelin-forming cells
19.07.2018 | Advanced Science Research Center, GC/CUNY
NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
20.07.2018 | Power and Electrical Engineering
20.07.2018 | Information Technology
20.07.2018 | Materials Sciences