Biology subjects

Bisazza, A.

Publications and source records attributed to Bisazza, A..

4 recordsLinked to original sources

bioRxiv2025

Inhibitory control in reptiles

Inhibitory control, the ability to suppress an automatic response in favour of a contextually appropriate alternative, is crucial for adaptive behaviour across animal species. While extensively studied in mammals and birds, research on reptiles remains limited, with comparisons hindered by methodological inconsistencies. Here, we assessed inhibitory control in two reptile species, Hermanns tortoise (Testudo hermanni) and the bearded dragon (Pogona vitticeps), using the transparent cylinder test--a method widely employed with mammals, birds, and fish. This test evaluates the ability to inhibit reaching directly for visible food through a transparent barrier. Both species exhibited lower inhibitory control than most amniotes, supporting the prevalent hypothesis linking inhibitory capacity to brain size. However, exceptions observed in various species suggest ecological and non-cognitive factors also shape these abilities. Notably, bearded dragons outperformed tortoises, despite their smaller size. In tortoises, females surpassed males, highlighting sex-based inhibitory differences in non-avian reptiles. Additionally, a positive correlation between lateralization and inhibitory control was observed in both species, providing the first evidence of such a link in reptiles. These findings emphasize the role of lateralization in reptilian cognition and suggest that inhibitory control across vertebrates is influenced by diverse factors, including brain size, ecology, and sex.

animal behavior and cognition↗

bioRxiv2022

Ontogeny of learning and visual discrimination in zebrafish

With the exception of humans, early cognitive development has been thoroughly investigated only in precocial species, well developed at birth and with a broad behavioural and cognitive repertoire. We investigated another highly altricial species, the zebrafish, Danio rerio, whose embryonic development is very rapid: 72 hours. The nervous system of hatchlings is poorly developed, and their cognitive capacities are largely unknown. Larvae trained at 8 days post-fertilisation rapidly learned to associate a visual pattern with a food reward, showing significant performance at 10 days post-fertilisation. We exploited this capacity to study hatchlings discrimination learning capacities. Larval zebrafish rapidly and accurately learned colour and shape discriminations. They also discriminated a figure from its mirror image and from its 90{degrees}-rotated version, although with lower performance. Our study revealed impressive similarities in learning and visual discrimination capacities between newborn and adult zebrafish despite their enormous differences in brain size and degree of development.

animal behavior and cognition↗

bioRxiv2021

The role of visual and olfactory cues in social decisions of guppies and zebrafish

Vision and olfaction are expensive to maintain, and in many taxa there appears to be a trade-off in investment between the two sensory systems. Previous work has suggested that guppies (Poecilia reticulata) and zebrafish (Danio rerio) may differ in the relative importance they place on these two senses in social interactions. In this study, we directly examined this issue by experimentally contrasting olfactory and visual information in social situations. In the first experiment, we found that guppies spent more time where conspecifics were visible than where they could smell them. On the contrary, zebrafish spent significantly more time in an empty compartment containing smell of conspecifics than in a compartment in which they only saw them. The difference was not large, suggesting that both species integrate various types of information to locate a nearby shoal. In two subsequent experiments, we studied the role of vision and smell in the discrimination of the quality of the social group, namely the number and the familiarity of its members. Zebrafish and guppies were confirmed to rely on different senses to estimate the size of a social group, whereas they did not differ in the discrimination of familiar and non-familiar conspecifics which appears to be based equally on the two senses. Similarly to what happens in other vertebrate clades, we suggest that, among teleosts, there are large differences in the relative importance of the different senses in the perception of the external world.

animal behavior and cognition↗

bioRxiv2017

Fish perform like mammals and birds in inhibitory motor control tasks

Inhibitory control is an executive function that positively predicts performance in several cognitive tasks and has been considered typical of vertebrates with large and complex nervous systems such as primates. However, evidence is growing that some fish species have evolved complex cognitive abilities in spite of their relatively small brain size. We tested whether fish might also show enhanced inhibitory control by subjecting guppies, Poecilia reticulata, to the motor task used to test warm-blooded vertebrates. Guppies were trained to enter a horizontal opaque cylinder to reach a food reward; then, the cylinder was replaced by a transparent one, and subjects needed to inhibit the response to pass thought the transparency to reach the food. Guppies performed correctly in 58 % of trials, a performance fully comparable to that observed in most birds and mammals. In experiment 2, we tested guppies in a task with a different type of reward, a group of conspecifics. Guppies rapidly learned to detour a transparent barrier to reach the social reward with a performance close to that of experiment 1. Our study suggests that efficient inhibitory control is shown also by fish, and its variation between-species is only partially explained by variation in brain size.

animal behavior and cognition↗