Animal Cognition最新文献

Corvids are one of the most prominent avian taxa for the study of animal behaviour and cognition, yet their vocal communication remains comparatively understudied. This special collection synthesizes current research on the ontogeny, mechanisms, functions, and evolutionary trajectories of corvid vocal systems through the lens of Tinbergen’s four questions. Contributions highlight early emergence of vocal individuality and socio-contextual plasticity in vocal behaviour across development. Corvid vocal sequences often conform to linguistic laws like Menzerath’s law, while also exhibiting context-sensitive modulation. Experimental work demonstrates advanced vocal flexibility and cognitive control: rooks can learn human verbal commands by attending primarily to auditory cues, and perceive rhythmic variations and flexibly adjust vocal timing in response to tempo and metrical changes, even without full entrainment, positioning corvids as promising models for exploring the evolutionary roots of rhythm and musicality. Field-based experiments show that female jackdaws recognize mates’ contact calls under natural conditions, supporting social coordination and pair-bond stability. Phylogenetic analyses demonstrate how ecological pressures and social complexity shape acoustic structure across the Corvidae family, while novel biologging and machine-learning approaches promise to overcome methodological challenges in studying vocal communication in corvids. Together, these findings position corvids as a powerful model for exploring the evolution of communication systems and their cognitive underpinnings.

Domestic dogs (Canis familiaris) show robust social engagement with both humans and conspecifics and frequently reside in multi-species households. Prior work has focused largely on the human–dog bond, yet less is known about how dogs allocate social proximity between humans and conspecifics when both are simultaneously available. In the present study, we implemented a two-choice social preference paradigm in adult companion dogs (n = 31). Pairs of familiar stimuli (owner, household dog, toy, or food) were presented in direct competition. Unlike go/no-go choice tasks, dogs freely explored an arena, allowing for continuous assessment of stimulus-directed behavior across a trial. Automated tracking was used to quantify spatial proximity-based social preferences. Competing social comparisons assessed allocation of proximity between an owner and a household dog. Competing non-social comparisons evaluated each social agent (owner or household dog) against a familiar non-social alternative (food or toy). Under competing social conditions, dogs spent more time in close proximity to their owner than to a household dog. In contrast, when each social agent was evaluated independently, dogs spent more time near both owners and household dogs than a familiar toy, but not food. These findings demonstrate context-dependent differences in stimulus-directed proximity in adult companion dogs, with owner prioritization observed under socially competing conditions.

Spatial cognition varies widely even among closely related species, and identifying the ecological drivers of this variation remains challenging because species typically differ in multiple aspects of their ecology simultaneously. Here we performed wild experiments to compare spatial navigation in seven related species of shell-dwelling cichlids from Lake Tanganyika that share fundamental aspects of their ecology but vary in home range size and shelter availability. We displaced territorial males at successively greater distances (30 cm to 15 m) from shelters, using video tracking and automated 3D terrain reconstruction to measure return paths and homing success. We complemented this with onshore experiments examining landmark use and memory for shell locations. Of the seven species tested, three (Lamprologus ornatipinnis, L. ocellatus, Neolamprologus meeli) reliably returned to their home shells while four species (N. multifasciatus, N. brevis, N. pulcher, Telmatochromis temporalis) sought shelter in the nearest refuge. Among the navigating species, homing success declined with displacement distance, and long-distance performance (at 15 m) differed: N. meeli (largest range, fewest shelters) succeeded in 80% of trials, while L. ocellatus and L. ornatipinnis (smaller ranges, marginally more shelters) succeeded in only ~ 10% of trials. Arena experiments revealed that the two better-performing species in the field preferentially searched in areas previously associated with their home shell, with N. meeli showing additional use of experimental landmarks. Our findings provide a detailed comparative foundation for future work, highlighting how ecological context shapes spatial cognition in natural populations.

Sex role differences can influence ecological and evolutionarily important traits like activity level and behavioural flexibility. In bumblebees, female workers are the main foragers for the colony, whereas males (drones) have minimal responsibility. However, males become solitary foragers once they leave the colony, suggesting that increased activity level and behavioural flexibility are crucial for their survival. Here, we conducted a laboratory experiment to compare male and female bumblebees’ active time in a novel environment (using an ‘activity’ task) as well as their colour-reward associative learning ability and behavioural flexibility (with a simultaneous two-choice discrimination-reversal colour learning task). As predicted, males were more active in the novel environment than females. Males and females showed comparable performance in learning the colour-reward association, but males demonstrated enhanced behavioural flexibility when the reward contingency changed. Males’ active time may reflect their exploratory behaviour (e.g., pre-mating patrolling), and their enhanced flexibility suggests their readiness to find new profitable flowers when exploited flowers decrease in quality. These results highlight the importance of these behavioural and cognitive traits for males, which may increase their chance of finding mates and improve their foraging efficiency.

The domestic dog is known for its strong ability to respond to human social cues. However, conclusions based on highly socialized dogs may not generalize to all populations since acquired experience is known to greatly influence canine cognition. To further explore this question, we employed a classic gesture comprehension paradigm to test a group of adolescent police dogs with distinct background. Results showed that these dogs exhibited a different social communicative cognition ability, characterized by an enhanced following of marker gesture but an impaired following of pointing gesture. Compared to public data, these police dogs performed significantly worse on the pointing gesture but much better on the marker gesture than assistance dog puppies. Their performance on the pointing gesture was comparable to wolf puppies’, whereas they significantly surpassed them on the marker gesture. Compared to free ranging dogs with limited socialization, they also showed a similar level of performance on the pointing gesture. Our findings shed new light on the cognitive differences among distinct dog populations and reveal acquired experience could greatly shape domestic dogs’ social cognition ability, serving as a critical supplement to existing results.

The prosocial choice paradigm is a widely used method in studies of prosocial behavior in chimpanzees, but findings produced using this approach have been inconsistent. One potential source of these discrepancies is the lack of control for motor lateralization. The present study examined the influence of motor lateralization on decision-making in four chimpanzees (Pan troglodytes) housed at the Warsaw Zoo. Subjects chose between prosocial (1/1) and selfish (1/0) tokens under three experimental conditions: (a) tokens randomly mixed within the feeder, (b) tokens arranged in single-color stacks on opposite sides, and (c) mixed tokens without a partner (ghost condition). Each individual made 200 decisions per condition over a three-month period. Results indicated that chimpanzees were significantly more likely to choose the prosocial option when token placement minimized lateralization effects through random mixing. In contrast, when tokens were presented in fixed locations, choices were systematically influenced by the physical convenience of reaching, reflecting individual motor preferences. These findings highlight the importance of controlling motor lateralization in studies using the prosocial choice paradigm. Even with motor lateralization controlled, the presence of a partner proved essential for demonstrating prosociality. Prosociality was not detected in the so-called ghost condition, where no partner is present. Future research should increase the number of trials, distribute sessions over time, randomize token placement, and examine the relationship between task-based decisions and broader patterns of social interaction.

Linguistic laws are increasingly used as markers of efficiency in non-human communication, but it remains unclear how rapidly these patterns can emerge. In this re-analysis of experimental data from James and Sakata (Current Biology 27:3676–3682, 2017), I assessed whether zebra finches tutored with songs with shuffled syllables, where each syllable type is equally common and songs have equal length, transform them to exhibit three linguistic laws associated with efficiency in human language. Menzerath’s law and Zipf’s rank-frequency law are present in the learned songs to a similar extent as in human language, while there is only weak support for Zipf’s law of abbreviation. These results suggest that some measures of language-like efficiency can emerge extremely rapidly, while others may require iterated social learning.

Domestic dogs rely on a sophisticated repertoire of visual displays to regulate social interactions. However, the interpretation of some of these displays, such as facial expressions, remain unclear. In the present study, we investigated the communicative strategies dogs’ employ to re-establish a positive interaction with humans. We adopted a modified version of the classical Still-Face Paradigm and introduced two non-responsive phases: the classical “still-face” phase (human attentive but unresponsive) and a novel “face-away” phase (human turned away and inattentive) to test the flexibility of communicative signals modalities used by dogs. The test was conducted with both the owner (attachment figure) and a familiar human (familiar dog trainer). Results showed that dogs displayed a rich repertoire of visual and facial signals, which may serve affiliative and communicative functions, particularly during the first interaction and, overall, more towards their owner compared to the familiar human. Confirming a still-face effect, the frequency and duration of these behaviours significantly decreased in the non-responsive phases, compared to the first interaction. Contrary to our predictions, no differences emerged between the still-face and face-away phases and the exhibition of signals generally decreased in subsequent phases indicating a possible carry over effect. The higher communicative persistence towards the owner compared to the familiar human underscores the crucial role of the attachment bond in shaping the dog’s communicative strategies. These findings highlight the attachment bond as a key factor in interspecific communication, extend current research on the still-face paradigm in domestic dogs, and provide a valuable methodological tool for future investigations.

To uncover universal principles of vocal behavior, studies have examined whether linguistic laws apply across species. Menzerath’s law, for instance, posits that larger constructs have shorter constituent parts, reflecting an efficiency principle that reduces articulatory and energetic demands. Another proposed universal is final lengthening, where end-of-sequence vocalizations are extended to potentially signal sequence boundaries. While studies have examined these temporal patterns in ecological communicative contexts, it remains unclear whether they also emerge in more constrained, externally instructed vocal responses. This study examines temporal patterns in vocal sequences during a numerically cued production task in crows and humans. While both species performed the same task, they differ in their numerical representations: crows rely on an approximate number system, whereas humans possess a symbolic understanding of number. Crows showed a negative correlation between sequence length and vocalization duration—consistent with Menzerath’s law—and a positive correlation between sequence position and duration, consistent with final lengthening. In contrast, humans exhibited the opposite: vocalization duration increased with sequence size and decreased with position. These findings suggest that Menzerath’s law is not a universal principle but shaped by species-specific cognition, motor constraints, and task demands. This highlights the importance of considering context and cognitive capacities when interpreting temporal patterns in vocal behavior across species.

In this study, we compared performance across four behavioural tasks in the same fish species (Rhinecanthus aculeatus), with one group held in long-term laboratory captivity and the other recently caught and temporarily housed at a field station laboratory. The aims of this study were twofold: first, to test whether captivity conditions influence performance in commonly used behavioural and cognitive assays; and second, to evaluate whether any of these tasks could serve as a practical tool for screening behavioural changes over time. The four tests used were a Novel Object Test, Puzzle Preference Test, Emergence Test, and Cylinder Test. We found that recently caught fish were generally more exploratory and more responsive to novel stimuli; however, their responses were object-specific, with increased neophobia towards some objects. Long-term captive fish were more variable in their responses across all tests. In the Emergence Test, long-term captive fish emerged faster but showed greater individual variability. In the Cylinder Test, all recently caught fish failed to swim around a transparent cylinder, whereas several long-term captive individuals showed possible evidence of inhibitory control. Our results demonstrate that captivity conditions can influence performance in behavioural tests at both group and individual levels. These findings have important implications for comparative cognition studies, particularly when interpreting results collected across different laboratory settings or captivity durations, even when working with the same species. Of the tasks used, the Emergence Test was identified as the most practical assay for tracking the effects of captivity on behaviour, as it was highly sensitive to individual differences and straightforward to run and analyse.