Prey quantity discrimination and social experience affect foraging decisions of rock lizards

Abstract

Animals often face situations that require quantity discrimination for decision-making.Differentiating between more and less amounts might be adaptative in different contexts such as in social relationships, navigation, or foraging. However, feeding close to conspecifics might change foraging behavior decisions due to changes in predation risk perception and competition for resources. Here, we tested quantity judgement abilities of foraging rock lizards (Iberolacerta cyreni) in a spontaneous choice test between 5 versus 10 cricket prey. Lizards tested had been previously housed alone or in a group to examine how social experience affected foraging decisions. Our results showed that 'Grouped' lizards had greater foraging activity than 'Solitary' lizards. Furthermore, all lizards demonstrated some ability to discriminate between the two amounts of prey.These results reveal the capability of quantity judgments in rock lizards and also that foraging decisions may be modulated by the previous social experience. Significance statementThe presence of food sources differing in quantity, together with the proximity of conspecifics can strongly affect foraging decisions. Previous studies showed various levels of quantitative abilities on different taxa, but results with reptiles are scarce and inconsistent. On the other hand, previous research showed that grouping may have a notable effect on foraging behavior. Here, we demonstrate that male rock lizards can discriminate between two amounts of prey and that there is an effect of the previous -4social experience on foraging behavior, as lizards that had been housed alone showed less interactivity with food. These outcomes reveal the existence of quantitative abilities in lizards and the importance of the previous social experience in foraging decisions.

Foraging decisions of rock lizards may be dependent both on current rival assessment and dear enemy recognition

“…In both treatments, when the intruder was either familiar or unfamiliar to the forager, the number of attacks directed to the high source of food was more frequent. This result fits with previous experiments made in this species in which there was a preference for the higher amount of food in absence of competitors (Recio et al, 2021).…”

“…According to previous findings in which I. cyreni was exposed to a similar foodchoice test (Recio et al, 2021), we expected that the lizards would interact more often with the highest food source (searching, hunting…). We expected that an animal would interact with a food source in presence of a conspecific intruder in a different way when the intruder was familiar (i.e higher frequency of interactions with the best food source) than when it was unfamiliar.…”

Reinstating reptiles: from clueless creatures to esteemed models of cognitive biology

“…Recent efforts surprisingly show that Italian wall lizards (Podarcis siculus) lack spontaneous quantity discrimination and learn numerical rules relatively poorly even after extensive training (Miletto Petrazzini et al, 2017. Nevertheless, other studies do demonstrate spontaneous quantity discrimination in the closely-related Carpetan rock lizard (Iberolacerta cyreni, Recio et al, 2021), gidgee skinks (Egernia stokessi, Szabo et al, 2021a), in Hermann's tortoises (Testudo hermanni, Gazzola et al, 2018) and Chinese stripe-necked turtles (Mauremys sinensis, Lin et al,in press,Figure 2C). Given the limited number of species tested on numerical cognition, its evolution throughout the reptile and vertebrate phylogeny remains disputed.…”