Previous investigations into referential use of object words by dogs have revealed limited understanding in this domain by most dogs. However, a recent study by Boros et al. (Current Biology, 34(8), 1750-1754, 2024) has provided neurological evidence suggesting that understanding of the referential nature of object words and the ability to form mental representations of objects may actually be prevalent among dogs.

A new study investigates how stingless bee colonies inherit one of two architecturally distinct types of comb and proposes the primary mechanism of inheritance as stigmergy: among-individual coordination in comb building informed by environmental cues (i.e., social artefacts). These findings highlight the importance of social information in creating and maintaining architectural variance among structures.

In a recent study, Johnson and Wynne found that dogs classically conditioned to associate electric shocks with chasing a fast-moving mechanical lure inhibited chasing behaviour at test, while dogs conditioned with food rewards did not learn any operant behaviours to substitute chasing and therefore continued to interact with the lure. Here, we raise questions about the suitability of the training protocols and challenge the conclusion that shock collars impose minimal welfare impacts.

Research has examined how stimulants affect impulsive choice in delay-discounting tasks, but little is known about whether such drugs influence how discounting varies with reward magnitude. This study sought to investigate the effects of acute and chronic methamphetamine administration on rats' responding in a rapid acquisition choice task in which reward delays were changed unpredictably across sessions. In each group of four sessions, delays were unequal (1 s/8 s, or 8 s/1 s) or equal (1 s/1 s, or 8 s/8 s) while reward magnitudes were constant and unequal (one dipper cycle/four dipper cycles). This enabled us to obtain both estimates of delay discounting (i.e., sensitivity to delay) and the magnitude effect (in which larger rewards are discounted at a lower rate). Methamphetamine was administered in increasing doses acutely and chronically. Baseline results showed that rats reliably preferred the alternative with a shorter delay and that choice for the larger reward was greater when the delays were long, consistent with the magnitude effect. Acute methamphetamine dose dependently reduced both sensitivity to delay and the magnitude effect, but not sensitivity to magnitude. Chronic administration had no systematic effect on choice. This study is the first to report a magnitude effect with rats in a rapid acquisition choice procedure similar to that found in delay discounting research with humans, and suggests that acute methamphetamine administration reduces control by contingencies that change across sessions.

Recent findings indicate that noise pollution - presented in the absence of other variables - has both immediate-term impacts on young birds' developmental rates and physiology as well as long-term effects on adult telomere length and reproductive success. This work highlights yet another set of negative impacts caused by anthropogenic noise, and suggests that the dramatic fitness consequences observed likely have implications for the evolution of learning and behavior in animals living in noisy environments.

Humans and other animals often seek instrumental information to strategically improve their decisions in the present. Our curiosity also leads us to acquire non-instrumental information that is not immediately useful but can be encoded in memory and stored for use in the future by means of episodic recall. Despite its adaptive benefits and central role in human cognition, questions remain about the cognitive mechanisms and evolutionary origins that underpin curiosity. Here, we comparatively review recent empirical studies that some authors have suggested reflects curiosity in nonhuman animals. We focus on findings from laboratory tasks in which individuals can choose to gain advanced information about uncertain future outcomes, even though the information cannot be used to increase future rewards and is often costly. We explore the prevalence of preferences in these tasks across animals, discuss the theoretical advances that they have promoted, and outline some limitations in contemporary research. We also discuss several features of human curiosity that can guide future empirical research aimed at characterising and understanding curiosity in animals. Though the prevalence of curiosity in animals is actively debated, we surmise that investigating behavioural candidates for curiosity-motivated behaviour in a broader range of species and contexts, should help promote theoretical advances in our understanding of cognitive principles and evolutionary pressures that support curiosity-driven behaviour.

Despite popular culture's promotion of the elephant's ability to "never forget," there is remarkably limited empirical research on the memory capacities of any living elephant species (Asian, Elephas maximus; African savanna, Loxodonta africana; African forest, Loxodonta cyclotis). A growing body of literature on elephant cognition and behavioral ecology has provided insight into the elephant's ability to behave flexibly in changing physical and social environments, but little direct evidence of how memory might relate to this flexibility exists. In this paper, we review and discuss the potential relationships between what we know about elephant cognition and behavior and the elephants' memory for the world around them as they navigate their physical, social, and spatial environments. We also discuss future directions for investigating elephant memory and implications for such research on elephant conservation and human-elephant conflict mitigation.

Many ant species can respond to dramatic changes in local conditions by relocating the entire colony to a new location. While we know that careful learning walks enable the homing behavior of foraging ants to their original nest, we do not know whether additional learning is required to navigate to the new nest location. To answer this question, we investigated the nest relocation behavior of a colony of Australian desert ants (Melophorus bagoti) that relocated their nest in response to heavy rainfall in the semidesert terrain of Alice Springs. We identified five types of behavior: exploration between nests (Old-to-New nest and New-to-Old nest), transport from Old to New nest, and relearning walks at Old and New nests. Initially, the workers performed relearning walks at the Old nest and exploratory walks between the Old and New nests. Once they completed the exploratory walks, the workers transported resources and brood to the new nest. Finally, we observed the workers performing relearning walks at the New nest. While the relearning walks at the Old nest were slow and appear to enable exploratory walks to the New nest, the relearning walks at the new nest were faster and appeared to enable homing from foraging trips. These observations shed insight on how learning helps these ants to respond to sudden changes in their environment.

Liao et al. demonstrated that crows can count out loud, revealing a level of vocal control previously unobserved in nonhuman species. This discovery suggests that rather than being judged by primate standards, birds might represent a new benchmark for vocal and perhaps broader cognitive abilities.

With the general aim of providing more evidence for considering certain behaviors involved in the act of remembering as operant, two experiments were carried out to verify its sensitivity to differential reinforcement, and to some of the variables upon which it depends. In the first experiment, three children participated, and two variables were manipulated in a "free recall" task: the accuracy of the instructions and the magnitude of the reinforcer applied to the emission of the target words. In the second experiment, 60 was changed to one of comparison between groups. In this case, the response-reinforcer interval (immediate vs. delayed) was manipulated using a "recognition" task. In both experiments, a greater number of remembered items were found in the presence of reinforcement compared to its absence, as well as with a greater magnitude of the reinforcer and with a shorter delay. These results are discussed considering the peculiarities of verbal behavior in humans and provide evidence that operant processes have an important role in traditional human memory tasks.

The "Spoon task" is a common measure of episodic future thinking (i.e., ability to imagine hypothetical future events) in children. However, by providing items and prompting children to choose one, this task might not require deliberate and goal-driven episodic future thinking. In contrast, "spontaneous" Spoon tasks may better reflect Tulving's original conception as they minimize environmental cues and verbal prompts. We identify challenges in designing such tasks, including removing the scaffolded intention to act and giving children permission and sufficient motivation to act. Drawing on the comparative literature, we propose methods to overcome these obstacles when designing spontaneous Spoon tasks. Furthermore, sampling from the work of Clayton and colleagues, we advocate for a multipronged approach including two or more of the following methods in order to capture spontaneous behavior: naturalistic observation, virtually administered tasks within the child's home, laboratory experiments, and questionnaires. Our review highlights the importance of spontaneous episodic future thinking and establishes a foundation for future methodologies to study this complex cognitive process.

Despite birdsong being one of the most studied models of sexual selection, how it operates in birds that sing only one song remains poorly understood. A recent study using a big data approach reveals a novel aspect of song that may potentially function as an honest signal of male quality and a way to maintain listener attention.

In complex social environments, animals benefit from suppressing inappropriate responses (known as Response Inhibition) to avoid conflicts and maintain group cohesion. Recent research suggests that an individual's early-life social environment can shape their response inhibition. However, these findings have mostly been correlational, and results vary across species. Furthermore, the role of learning is often overlooked when measuring response inhibition, despite its potential importance to understanding group differences. We investigated the effect of early-life group size, a key determinant of social complexity, on response inhibition in Japanese quails (Coturnix japonica), whilst taking the role of learning into account. Quails (n = 120) were raised in either small groups of five or large groups of 15 individuals. Response inhibition was assessed using the cylinder task. Up to ten trials were administered to assess whether the birds' responses changed with increasing experience of the task. Among the quails that completed ten trials, we found that those raised in large groups consistently spent less time pecking the cylinder than those raised in small groups. The quails' responses were also influenced by their body condition, food motivation and sex. Importantly, the quails learned to inhibit their responses - successful trials increased, and time spent pecking the cylinder decreased, across ten trials. However, learning rates did not differ between the treatment groups. These findings suggest that early-life social group size promotes the development of response inhibition in quails, but not their learning of it, during the cylinder task.

One of Clayton's major contributions to our understanding of animal minds has been her work on episodic-like memory. A central reason for the success of this work was its focus on ecological validity: rather than looking for episodic memory for arbitrary stimuli in artificial contexts, focussing on contexts in which episodic memory would serve a biological function such as food caching. This review aims to deepen this insight by surveying the numerous functions that have been proposed for episodic memory, articulating a philosophically grounded framework for understanding what exactly functions are, and drawing on these to make suggestions for future directions in the comparative cognitive psychology of episodic memory. Our review suggests four key insights. First, episodic memory may have more than one function and may have different functions in different species. Second, cross-disciplinary work is key to developing a functional account of episodic memory. Third, there is scope for further theoretical elaboration of proposals relating episodic memory to food caching and, in particular, future-oriented cognition. Finally, learning-related functions suggested by AI (artificial intelligence)-based models are a fruitful avenue for future behavioural research.

New research is shedding light on the nuances and complexity of social relationships in our closest relatives, revealing cooperative intergroup relationships in bonobos, in contrast to lethal intergroup violence in chimpanzees. At the same time, intragroup relationships, at least among males, are characterized by higher frequencies of aggression and lower rates of coalitionary cooperation in bonobos than chimpanzees.

Domestic dogs (Canis familiaris) have been documented to 'overimitate' humans - a form of social learning - by copying their causally-irrelevant actions. It is suggested that this behaviour results from social, affiliative motivations. Dogs have also been known to behave differently when they are being watched (or not) by humans, such as by following commands better (or worse). In this study, we tested whether dogs' copying behaviour would also be sensitive to their caregiver's attentional states. The subject's caregiver demonstrated irrelevant and relevant actions in the dot-touching overimitation task, then during trials the caregiver was either watching their dog or turned away. Our results revealed no difference in dogs' irrelevant-action copying; however, we found that dogs approached the dots less per trial when their caregiver was watching them. Dogs also copied their caregiver's leftward sliding of a door (to obtain a food reward) more accurately when they were being watched by their caregiver. Finally, dogs who copied the irrelevant action did so more often after obtaining their food reward, which supports that these dogs may have had two separate goals: a primary instrumental goal and a secondary social goal.

The order of stimuli within sequences and the transitional probabilities (TPs) it generates are central information in sequence processing. However, less is known about what type of information and how it is extracted by general learning mechanisms. The present study focused on statistical learning of second-order TPs. Second-order TPs are involved when only the combination of two stimuli predicts the third. In a first experiment, TPs depended crucially on the order of presentation of a pair , which led to different predictions depending on the order of the stimuli (i.e., ABC vs. BAF). Eight visuomotor sequences governed by second-order TPs were used and response times (RTs) were recorded for each transition. The task included a learning phase followed by a switch phase during which the second-order TP were reversed (e.g., the sequences ABC and BAF became respectively ABF and BAC). A decrease of RTs between the second and the third stimulus during the learning phase and an increase of RTs during the switch phase suggested that variations of orders within second-order TPs could be learned. Further analyses, however, indicated that such learning was difficult for most participants. A second experiment showed that the difficulty of learning was not solely due to the difficulty to pick up the effect of order of presentation, but that learning second-order transitional probabilities in addition to order would be the main obstacle. These experiments suggest that statistical learning is capable of learning complex associations, even if this remains a challenge for human cognition.

Researchers have recently described the wing-fluttering signal of Japanese tits and eyeblink signal of concave-eared torrent frogs as bodily communication that elicits specific responses. I assess the evidence that these may be intentional, goal-directed signals using established criteria for gestural communication.

The New York Declaration on Animal Consciousness (Andrews et al., 2024) highlights increasing empirical evidence supporting the existence of sentience in many animal species. The views in the declaration rest on an increasingly popular theoretical approach that comparative psychologists could use to guide research on non-human consciousness.

Although the diversification of species has fascinated researchers for centuries, we know remarkably little about how behavior influences niche adaptation and the genetic mechanisms through which behavior evolves. In their recent study, Sommer-Trembo et al. (Science, 384, 470-475, 2024) demonstrate a critical role for the regulatory gene cacng5b in modulating phenotypic variation in exploratory behavior in one of the most exceptional adaptive radiations: the African cichlid fishes of Lake Tanganyika.