Wall lizard becomes accustomed to humans and stops hiding

 Date: March 27, 2017

Source: FECYT - Spanish Foundation for Science and Technology

Habituating to predators or fleeing and hiding are tactics that vary between species. Scientists from two research centres in Italy and Spain have observed that adult male common wall lizards sharing their living spaces with humans become accustomed to them and hide less when humans approach them. Yellow lizards were the most "daring."

Humans have an increasing presence in different species' natural habitats. For this reason, scientists are investing much time in studying wild animals' capacity to tolerate these disturbances. Lizards are an appropriate model for research into this subject, as they can be found in high densities in many environments and are relatively easy to observe in the field and handle in laboratories.

Scientists from the Eco-Ethology group of the University of Pavia (Italy) and the National Museum of Natural History (CSIC) in Spain used the lizards to analyse their reactions to attacks by human predators and the strategies they adopt, depending on the local risk level. To do this, they simulated human attacks on two populations in completely different settings: rural and urban habitats.

"The species we used in the study was the common wall lizard (Podarcis muralis). The main aim was to detect the possible influence of urbanisation on their antipredator response in terms of activity, time spent hidden in refuges after attacks and habituation to predators after repeated attacks," Sinc was told by Jose Martín of the Spanish National Museum of Natural History and co-author of the paper, published in the journal Animal Behaviour.

The findings show that urban lizards spend less time in their refuges following simulations of predator attacks and that the become habituated, as their successive hiding times decreased faster than those of the rural lizards. This detail suggests different levels of caution against potential predators. 

Continued