Australian researchers have discovered that sleepy lizards (Tiliqua rugosus) can recognise the smell of smoke as a sign of approaching fire and attempt to escape, but they do not respond to the sound of fire.
The study, published this month in Biology Letters, provides the first empirical test of an amusing anecdote: when zookeepers at a US zoo burnt their lunch, they noticed they were not alone in smelling the acrid smoke. Captive sleepy lizards became agitated by the smell wafting through the building, while other reptiles remained calm. Despite being mostly captive-bred, the lizards tongue-flicked, paced, and tried to escape—behaviour researchers now show appears innate, not learned.
"Many animals from fire-prone regions, such as Australia, appear to have this miraculous ability to survive their homes being burnt. Our study demonstrates that some lizards innately recognise smoke as a cue of approaching fire and respond by running away," said lead author Dr Chris Jolly of Macquarie University.
Why it matters
With wildfires intensifying under climate change, understanding how animals survive fires is critical. While people often assume wildlife caught in fires have little chance of survival, research is revealing that many species have evolved strategies to detect and escape fire.
This study suggests that fire-prone environments have shaped the sensory systems and behaviours of animals such as sleepy lizards, enabling them to respond to smoke as an early-warning signal.
"As fires become more frequent, intense and unpredictable—including in habitats that rarely burned in the past, like rainforests—we need to know which species can respond to fire cues, and which are most vulnerable," Dr Jolly said.
Study details
- Researchers exposed sleepy lizards to smoke and to the crackling sound of fire, paired with appropriate controls.
- Lizards fled from smoke but not from sound, showing their response is tuned to olfactory cues.
- The findings support the idea that species from fire-prone regions evolved behavioural adaptations to survive wildfire.
Broader impact
The work highlights the urgent need to understand animal survival strategies in a rapidly changing climate. Fires are becoming more destructive worldwide, and biodiversity loss is accelerating as species face novel fire regimes.
Authors: Dr. Chris Jolly (Macquarie University and Charles Darwin University), Prof. Dale Nimmo (Charles Sturt University), Dr. Alex Carthey (Macquarie University), Ms. Emma van de Pas (Van Hall Larenstein University of Applied Sciences, The Netherlands), and Prof. Martin Whiting (Macquarie University).
Journal: Biology Letters, August 2025.
