Lizards smell wildfires

The evolutionary role of fire in animals has been poorly explored [1]. We recently conducted an experiment with the mediterranean lizard Psammodromus algirus to evaluate a possible adaptive response to fire [2]. Specifically we tested whether detecting a fire by smoke is adaptive for lizards living in fire-prone ecosystems. To do so we collected lizards from habitats with contrasted fire regimes (fire-prone shrublands vs. non-fire-prone dunes) and exposed them to smoke and to a false smoke (control) in a terrarium. We video-recorded the behavioral reaction to the treatments, and determined whether each individual detected the smoke and the intensity of the reaction. We found that in populations from fire-prone habitats, more lizards reacted to smoke, and their behavioral response was more intense than in lizard populations from non-fire-prone habitats. Our results suggest that the enhanced response to smoke may have been selected as adaptive behavior in fire-prone habitats to increase survival. Smoke has been considered a very important cue for enhancing germination in plants [3]; now we show that is also a cue for fire avoidance in animals. To our knowledge, this is the first evidence of smoke detection by reptiles in wild populations. 

References

[1] Pausas JG, Parr CL 2018. Towards an understanding of the evolutionary role of fire in animals. Evol. Ecol. 32: 113–125. [doi | pdf]

[2] Álvarez-Ruiz L, Belliure J, Pausas JG. 2021. Fire-driven behavioral response to smoke in a Mediterranean lizard. Behavioral Ecol. [doi |oup | data:dryad | pdf]  [ver también: ¿Cómo sobreviven los animales a los incendios?]

[3] Keeley & Pausas 2018. Evolution of ‘smoke’ induced seed germination in pyroendemic plants. S. Afr. J. Bot. 115: 251-255. [doi | pdf];  Moreira & Pausas 2018. Shedding light through the smoke on the germination of Mediterranean Basin flora. S. Afr. J. Bot. 115: 244-250. [doi | pdf];  Tormo et al. 2014. Field evidence of smoke-stimulated seedling emergence and establishment in Mediterranean Basin flora. J. Veget. Sci. 25: 771-777. [doi| pdf];  Moreira et al. 2010. Disentangling the role of heat and smoke as germination cues in Mediterranean Basin flora. Ann. Bot. 105: 627-635. [pdf | doi]