October 22, 2025
2 min read
Zoo Lunch Mishap Reveals Lizards’ Hidden Fire Detector
Australian “sleepy” lizards are not so sleepy when it comes to fire
The smell of smoke activates this otherwise “sleepy” lizard Tiliqua rugosa, also known as the shingleback skink or bobtail lizard.
A burned lunch at Audubon Zoo in New Orleans did more than just disappoint a hungry staffer. As soon as a smoke plume from the mishap drifted into their enclosure, Australian sleepy lizards suddenly stopped whatever they were doing—heads up, tongues flicking, bodies tense—and began pacing their enclosure’s edges and digging in the substrate, frantic to escape. Other reptile species in the same room didn’t flinch.
The incident sparked a scientific hunch: perhaps the lizards, which happen to be residents of particularly fire-prone regions, had evolved to recognize a blaze’s chemical cues.
To test this hypothesis, Chris Jolly, a conservation biologist at Macquarie University and Charles Darwin University in Australia, and his colleagues exposed 10 adult female sleepy lizards to individual puffs of smoke and water vapor and separately to recordings of crackling wildfires and white noise. The lizards fled in response to smoke but were unphased by water vapor, wildfire sounds or white noise. The findings, published in Biology Letters, suggest these lizards rely on smell—not hearing—to detect fire at long range, unlike some other lizards, frogs and bats.
On supporting science journalism
If you’re enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.
This aligns with Australian sleepy lizards’ known use of scent to recognize partners, with whom they form pair-bonds for life, and to find food and detect predators. “Smoke also tends to travel ahead of the flames and cuts through background noise,” Jolly says, “making smell a more reliable early warning than sound in open, windy, noisy environments.”
Many of the lizards tested had likely never experienced wildfire; their capture site hadn’t burned in more than 50 years. Yet they still bolted when they sensed smoke, suggesting an innate adaptation. (The strong response was particularly notable given the animals’ typical slow, deliberate movements, which Jolly assumes inspired the “sleepy lizard” designator: “They’re rarely in a rush to do anything, except, apparently, to escape from fire!”)
Juli Pausas, a research scientist at the Spanish National Research Council, who was not involved in the study, says that while the sleepy lizards’ reaction to smoke could indeed represent adaptation to fire—something also seen in some bat species, pygmy possums and Mediterranean lizards—future studies will have to rule out other explanations, such as a general aversion to smoke toxins.
“Nevertheless, the paper contributes to the emerging recognition that certain animal behaviors may represent fire adaptations, a topic that has been underexplored until recently,” Pausas says. As fires intensify amid climate change, the paper authors say, these sensory skills could mean the difference between survival and death.
It’s Time to Stand Up for Science
If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.
I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.
If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.
In return, you get essential news, captivating podcasts, brilliant infographics, can’t-miss newsletters, must-watch videos, challenging games, and the science world’s best writing and reporting. You can even gift someone a subscription.
There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.