Ruth Dolado

Habituation plays a key role in shaping the collective behavior of moving animal groups, yet the effects of variation in habituation within groups are unknown. Here, we merge two subgroups of fish with different levels of habituation and quantitatively analyze their movement. Non-habituated fish (not familiar with their swimming environment) tend to occupy more central positions within the group and position themselves closer to neighbors, consistent with the selfish herd hypothesis. This behavior appears to be driven by adjusted effective local interactions with nearby individuals. Compared to more habituated fish, these individuals also exhibit greater coordination, shorter burst-and-coast dynamics, more efficient information transmission, and a stronger tendency to adopt follower roles. To validate the findings, we develop a machine learning tool that successfully classifies the subgroup identity of individual fish. Our study demonstrates how differences in local-scale inter-individual interactions can drive spatial assortment within groups, based on heterogeneity in their manipulated exposure to the experimental setup.

This study examines how motivational profiles and absenteeism patterns jointly predict academic performance in higher education. Using an intensive 14‑week longitudinal design, we measured multiple forms of academic motivation (intrinsic, identified, introjected, extrinsic, and amotivation), combined self‑reported and QR‑based attendance, and tracked perceived performance throughout the semester. Longitudinal k‑means clustering yielded two robust profiles: a group with higher intrinsic and internalized extrinsic motivation and a more amotivated group. Compared with amotivated students, motivated students consistently reported higher perceived performance and lower absenteeism, although no significant differences emerged in final grades. Findings support the value of person‑centered, longitudinal approaches for understanding academic behaviour and informing targeted interventions on attendance and motivation.

The species of the Macaca genus are classified into four social styles based on aggression and affiliative patterns, as well as their phylogenetic relationships. However, some studies suggest that social parameters can change under different local conditions, particularly in semi-free-ranging environments. The aim of our study was to examine whether the social parameters (aggression, affiliative behaviors and spatial distribution) of two groups of macaques in semi-free-ranging conditions aligned with their expected social styles. We studied a group of Macaca tonkeana (nine individuals), which the social style expected is high tolerant, and a group of Macaca fascicularis (nine individuals), which the social style expected is low tolerant. Our results indicated that some social parameters in these groups did not conform to the expected parameters. M. tonkeana exhibited lower tolerance than expected, while, conversely, the aggression patterns of M. fascicularis resembled more tolerant behaviors. These findings suggest that group characteristics, such as semi-free-ranging conditions, should be considered when analyzing social parameters like aggression, affiliative behavior, and spatial distribution.

Organizing contextual or antecedent variables (motivating operations) may impact the occurrence of challenging behaviors engaged by students with intellectual disabilities. The present study aims to explore to what extent the structured playground has an impact on these behaviors, acting as a motivating operation. Doing so, an intervention with an ABAB design has been carried out. Results of the study show that the occurrence of challenging behaviors decreases when the playground presents different activities. These results are discussed according to the literature. In fact, enriching educational contexts and adapting them to the behavioral needs of students is essential to create safe, positive and preventive environments.

Many fish schools are regarded as leaderless, where any individual can guide the direction of group motion at any given moment. We conditioned a fish school of black neon tetra (Hyphessobrycon herbertaxelrodi) to find food in aparticular location, while another group swam freely with no particular goal. Groups were composed of similar individuals in terms of body size, task knowledge and hunger level. Our hypothesis was that leadership would be less stable when fish were conditioned than when they were not. Although stability tended to be greater in the conditioned group, the hypothesis was not confirmed, as both groups showed asimilar degree of leadership stability. Leadership was not entirely random and some individuals took the lead more often than others. Leaders tended to be at the front of the school and their tendency to lead was loosely related to higher swimming speeds, and not related to task knowledge.

Studying the collective behavior of fishes often requires tracking a great number of individuals. When many fishes move together, it is common for individuals to move so close to each other that some fishes superimpose themselves on others during one or several units of time, which impacts on tracking accuracy (i.e., loss of fish trajectories, interchange of fish identities). Type 1 occlusions arise when two fishes swim so near each other that they look like one long fish, whereas type 2 occlusions occur when the fishes’ trajectories cross to create a T- or X-shaped individual. We propose an image processing method for resolving these types of occlusions when multitracking shoals in two dimensions. We assessed processing effectiveness after videorecording shoals of 20 and 40 individuals of two species that exhibit different shoal styles: zebrafish (Danio rerio) and black neon tetras (Hyphessobrycon herbertaxelrodi). Results show that, although the number of occlusions depended on both the number of individuals and the species, the method is able to effectively resolve a great deal of occlusions, irrespective of the species and the number of individuals. It also produces images that can be used in a multitracking system to detect individual fish trajectories. Compared to other methods, our approach makes it possible to study shoals with water depths similar to those seen in the natural conditions of the two species studied.

Based on previous models (Hemelrijk 1998; Puga-González, Hildenbrant & Hemelrijk 2009), we have developed an agent-based model and software, called A-KinGDom, which allows us to simulate the emergence of the social structure in a group of non-human primates. The model includes dominance and affiliative interactions and incorporates two main innovations (preliminary dominance interactions and a kinship factor), which allow us to define four different attack and affiliative strategies. In accordance with these strategies, we compared the data obtained under four simulation conditions with the results obtained in a previous study (Dolado & Beltran 2012) involving empirical observations of a captive group of mangabeys (Cercocebus torquatus). The results show that the combination of the effect of kinship on affiliative interactions and the use of ambiguity-reducing attack provide results that are the most similar to the results of the biological model (i.e., a captive group of mangabeys) used in this study.