Rodents exhibit exploratory behaviors, such as rearing and digging, in both novel and familiar environments, which serve to monitor their surroundings. Variations in these exploratory behaviors can serve as sensitive indicators of subtle behavioral effects induced by stressors, including sleep deprivation. Disrupted maternal sleep during gestation has been consistently associated with adverse behavioral outcomes in both the mother and her offspring. Several studies have reported that sleep restriction in late pregnancy increases ultrasonic vocalizations, promotes greater novelty-seeking and risk-taking, and increases activity levels in juvenile and adolescent rodents. However, the neonatal stage remains relatively understudied, despite its critical importance for sensory and motor development. Pregnant BALB/c mice underwent a standardized sleep-deprivation protocol for seven consecutive days (gestational days, GD7-14). Behavioral assessments were conducted in home-cage conditions immediately post-deprivation (GD14), during the recovery phase (GD18), and during the postpartum period (PPD3). Early locomotor behavior was evaluated in offspring of sleep-deprived dams using an open-field test on postnatal day 7 (PND7). Dams exhibited marked increases in mobility, rearing, grid climbing, digging, and spontaneous jumping during the sleep-deprivation days (n = 13 dams) compared with controls (n = 6 dams), with these effects persisting during the recovery period. In the postgestational period, a subset of these dams (n = 5) who delivered viable offspring normalized the frequency of these behaviors, but another subset of sleep-deprived dams who experienced miscarriage (n = 8) persisted with a higher frequency of rearing. Notably, offspring born to sleep-deprived dams showed significant locomotor hyperactivity in an open-field test compared with their controls (n = 15 pups per group). These results highlight that gestational sleep deprivation not only alters maternal exploratory patterns but also programs early offspring locomotor hyperactivity, underscoring its lasting impact on behavioral development.

This study examines differences in response patterns based on associative learning strategies, focusing on goal-tracker (GT) and sign-tracker (ST) profiles in rats. To explore whether maturational processes influence the expression of these phenotypes, Experiment 1 analyzed the distribution of ST and GT profiles across developmental stages (6- and 16-week-old rats). The results indicated a developmental effect on response patterns; younger rats exhibiting a higher prevalence of the GT profile, and no significant sex differences were observed. Experiment 2 assessed the ability of GT and ST animals to suppress their previously expressed behavioral patterns using an omission training procedure. Adult rats demonstrated greater response suppression than adolescent rats. Furthermore, GT profiles showed greater sensitivity to response omission than ST profiles, suggesting that these differences may be related to prefrontal cortex maturation. Sex differences emerged as a crucial factor in adult rats, with female GTs displaying more effective omission than female STs. This finding is particularly important because it may reflect behavioral phenotypes associated with psychiatric disorders, including substance abuse. Taken together, these results highlight how developmental stage and sex influence response profiles in rats, providing translational clinical relevance for understanding core symptoms in neuropsychiatric disorders.

Jellyfish of the genus Aurelia possess a decentralized nervous system and rhopalia that contain basic visual structures, providing a unique opportunity to explore light-driven behavior in the absence of a centralized brain. Despite their anatomical simplicity, little is known about how these animals modulate their motor activity in response to light or whether they exhibit consistent preferences for light or dark environments. In this study, we conducted two behavioral experiments to investigate the light-dependent behaviour in juveniles of Aurelia coerulea. In Experiment 1, we measured pulsation frequency under light and dark conditions as a proxy for motor activity. In Experiment 2, we adapted a scototaxis-based test to assess phototactic preferences in an environment divided into illuminated and dark compartments. Our results show that jellyfish increased pulsation rates under light conditions and spent significantly more time in the illuminated area, suggesting a consistent positive response to light. These findings provide evidence of light-mediated behavior in Aurelia coerulea and contribute to a deeper understanding of how complex sensory-guided behaviors can emerge in organisms without centralized nervous systems.

Conspicuous polymorphisms provide natural tests of mechanisms maintaining behavioral and underlying genetic variation. Cognition has received relatively little attention in color-polymorphic systems. We used a melanin-based polymorphism in the eastern mosquitofish (Gambusia holbrooki) to ask whether performance in a detour task differs between morphs. Melanic males (N = 38) solved the task more often than silver males (N = 37) and had a 1.59-fold higher estimated solution rate, although effect sizes were modest and statistical support was limited. These results suggest that processes associated with detour-task performance may represent an underappreciated axis of morph divergence with a potential role in the maintenance of melanin-based polymorphism.

The estrous cycle of female mammals does not only cause regular changes in steroid hormone concentrations but can also influence behavior and hence (social) life. A valuable model organism to study such effects is the guinea pig: its long 16-day estrous cycle with an active luteal phase represents a perfect opportunity to investigate the estrous cycle in detail, but information on estrous cycle effects is scarce. This study investigated the proestrus/estrus and diestrus phases of two consecutive cycles in twelve socially housed female guinea pigs. Following cycle monitoring, sociopositive and aggressive behavior, general activity patterns, anxiety-like behavior, and saliva cortisol concentrations were investigated on three days around estrus (day -1, day 0 = estrus, day 1) and in diestrus (day 7, day 8, day 9) each. Aggressive behavior significantly increased on day 0 (estrus) and the guinea pigs spent less time in the shelters and more time feeding on day 9 compared to day 7 in diestrus. Cortisol concentrations were increased around the time of estrus versus diestrus and body mass was decreased on day 0. None of the behavioral parameters affected cortisol concentrations considerably, except for a weak negative effect of the time spent feeding. This study demonstrates that the estrous cycle exerts an effect not only on physiological parameters but also on the behavior of group-living female guinea pigs. This represents an important starting point for future research and highlights stronger consideration of the estrous cycle when investigating (social) behavior and physiology in female guinea pigs.

Animal models remain essential in translational research, particularly in neuroscience, where behavioral assessments are used to investigate brain function and disease mechanisms. However, conventional statistical approaches, focused on frequencies, durations, and correlations, provide limited insight into the temporal organization and dependency structure of behavior. These methods treat behaviors as isolated or aggregated events, often overlooking the sequential, hierarchical, and dynamic nature of behavioral expression. This perspective advocates the adoption of analytical frameworks that integrate pattern-oriented and time-series dependency inference approaches. Tools such as THEME enable the detection of non-random, temporally structured behavioral sequences (T-patterns), revealing how behaviors are hierarchically organized over time. To further incorporate the possibility of assessing directed dependencies in behavioral sequences, tools such as Tigramite can be useful. Under specific assumptions, this tool allows the estimation of time-lagged, confounder-controlled, conditionally independent relationships between behaviors, representing them as dynamic interactions established over time. By combining these approaches, researchers can move beyond descriptive analyses toward generating hypotheses about the temporal organization and interdependence of behavioral events. Animal models of conditions such as drug addiction, autism spectrum disorder, anxiety disorders, and Alzheimer's disease, among others, in which traditional measures incompletely capture the richness of behavioral interactions, could benefit from this approach. Time-series inference methods may help identify candidate behavioral predictors and generate testable hypotheses about underlying pathophysiology. Overall, adopting this integrative, time-resolved analytical strategy may enable more comprehensive, reproducible, and biologically meaningful insights from animal models.

Utilizing shelters and living in groups are key anti-predator strategies among fish. Species that have evolved under different ecological conditions may exhibit distinct escape behaviors, reflecting variations in cognitive ability and social information transfer. This study investigate3-fishesd how group size and visual landmarks shape collective escape behavior in fish species from divergent flow habitats: the demasoni cichlid (Chindongo demasoni, preferring stagnant water), zebrafish (Danio rerio, preferring slow-flowing water), and qingbo (Spinibarbus sinensis, preferring fast-flowing water). For each species, 1080 individuals were tested in a between-subjects design, distributed into groups of 3 or 6 with or without landmarks. Using a Y-maze, we assessed the effects of shoal size (3 vs. 6) and the presence of visual landmarks on escape accuracy and latency to enter a shelter arm following brief environmental exploration and a simulated predation stimulus. Results indicated that distinct anti-predator strategies were shaped by species-specific cognitive profiles. The demasoni cichlid exhibited the most cognitively flexible behavior, including rapid decision making and a landmark-dependent shift from passive sheltering to active patrolling. In contrast, zebrafish responded with a generalized increase in shelter use, whereas qingbo behavior was strongly mediated by group competition. The benefits of larger group size and landmark presence were context-dependent, challenging the universal applicability of collective intelligence theory. Our findings demonstrate that anti-predator decision making is deeply rooted in species' evolutionary histories, providing crucial insights for developing conservation strategies that account for behavioral adaptation and cognitive ecology.

Understanding how vocal individuality evolves is important to explaining the organization of animal communication systems, especially where reliable recognition is essential for social interactions. Ancient murrelets (Synthliboramphus antiquus) and crested auklets (Aethia cristatella) are closely related alcids that differ markedly in chick developmental strategies. Murrelet chicks leave the nest burrow shortly after hatching and follow their parents to sea, whereas auklet chicks remain underground until fledging. These contrasting life histories provide a natural model for testing how developmental strategy influences the vocal individuality. We recorded calls of 1-7-day-old chicks of both species on Talan Island (Sea of Okhotsk; total n = 101) and analysed them to assess individual and brood-level variation. We further evaluated how analytical approach and sample size affect the detectability of individual differences. Calls differed strongly between species: murrelet calls had higher fundamental frequencies and occurred in series of 3-8, whereas auklet calls were structurally simpler. Individual vocal differences were present in both species but were substantially more pronounced in murrelets. Discriminant function analysis based on multiple acoustic parameters outperformed classification based on dynamic time warping of entire frequency contours. Increasing sample size reduced individual classification success in auklets but not in murrelets. In murrelets, family effects were also pronounced, with half of the measured parameters showing stronger brood-level than individual-level variation. Our results demonstrate that developmental strategy strongly shapes vocal individuality in related species. In the absence of reliable visual or spatial cues, selection appears to favour highly individualised calls supporting parent-offspring recognition.

Males and females, especially in species with more pronounced sexual dimorphisms, may face very different trade-offs between detecting and avoiding predation threats and the need to court potential mates. Within aquatic ecosystems, the use of reliable publicly available chemosensory risk assessment cues allows prey to assess local threats and optimize these behavioural decisions. Recent studies suggest in species with more pronounced sexually dimorphisms, males may show reduced responses to acute predation cues due to the potentially high costs of lost mating opportunities. However, in species that are less sexually dimorphic, males and females might be expected to respond to acute predation cues in a similar fashion. Here, we conducted laboratory trials to test the effects of sex and size (as a proxy for reproductive state) on the response to acute predation cues in wild caught Hart's rivulus (Anablepsoides hartii), a species with relatively low levels of sexual dimorphism. We quantified the antipredator response of reproductive and non-reproductive males (n = 50) and females (n = 49). Focal individuals were exposed to conspecific alarm cues (AC), conspecific disturbance cues (DC), or a water control (W). We found sex differences in baseline activity (before introduction of cues); females spent more time under shelter compared to similar sized males. Despite these differences, we found that male and female rivulus exhibited similar responses to acute risk cues regardless of size. Our results are consistent with the hypothesis that in the absence of strong sexual dimorphisms, male and female rivulus maybe subject to similar behavioural trade-offs in response to predation threats.

Discriminating between familiar and unfamiliar conspecifics is a fundamental aspect of social recognition. Previous studies have shown that familiarity strongly influences rat social behavior, and that rats can be trained to discriminate between olfactory cues from cage-mates and non-cage-mates in a digging task. However, such discrimination did not occur in a lever-pressing task using live conspecifics as stimuli. In the present study, we investigated whether rats could discriminate social familiarity in a simple, less-demanding and naturalistic context using whole-animal stimuli. We employed a habituation-dishabituation paradigm in which multiple cage-mate or non-cage-mate individuals were presented during the habituation phase. We examined whether rats would habituate to the familiarity category among these multiple stimuli and subsequently show dishabituation when the stimulus class switched (cage-mate to non-cage-mate or vice versa). During the habituation phase, exploratory responses declined over successive sessions, suggesting habituation to the common element among multiple cage-mates or non-cage-mates, i.e., familiarity/unfamiliarity. When all subjects were considered together, clear dishabituation was not observed, indicating substantial individual variation in habituation. However, a post-hoc exploratory analysis restricted to subjects showing sufficient habituation revealed significant dishabituation to the stimulus class switch. These findings suggest that responses to changes in social familiarity are not uniformly expressed across individuals; however, some rats exhibit response patterns consistent with class-level discrimination of social familiarity, highlighting variability in how rats perceive and respond to social information.

Tree cavities that accumulate water (dendrotelms) represent ecologically important microhabitats and can serve as critical drinking sites for wildlife, particularly under increasing drought conditions. Although their use by birds and small mammals is well documented, interactions involving large carnivores in temperate forests remain largely unexplored. Here, based on the available literature, we describe what appears to be the first report of a paw-mediated drinking behaviour in the critically endangered Marsican brown bear (Ursus arctos marsicanus) recorded in the central Apennines (Italy). Camera-trap monitoring of a beech (Fagus sylvatica) tree over a five-month period revealed that bears typically drank by immersing the muzzle into the cavity during summer, when water levels were high. In early autumn, however, reduced precipitation led to a drop in cavity water level, making direct access impossible. Under these constrained conditions, bears adopted an alternative technique: repeatedly inserting a forepaw into the cavity, wetting it, and licking the water from the paw. This paw-mediated behaviour, observed in two prolonged sessions (14-16 min each), reflects behavioural flexibility under restricted access to water. These observations broaden current understanding of drinking ecology and context-dependent behavioural variation in bears, and emphasize the role of dendrotelms as previously overlooked seasonal water resources for large mammals. Further monitoring is required to assess how widespread this behaviour is and under which environmental conditions it is likely to occur.

Orb web construction behavior offers unusual advantages for understanding the mental processes of an arthropod, because an orb weaver's intentions, perceptions, and decisions can be deduced in some contexts by observing the movements of her legs, just as one can make similar deductions from observing how a blind man moves his cane. This study shows that when spiders of two species were experimentally interrupted during orb construction, they remembered for up to several minutes the portion of the web in which they had been working, the type of activity in which they had been engaged, the direction in which they had been moving (left vs right, clockwise vs. counterclockwise), and the location of the hub. Biases in the searching behavior of legs in other contexts revealed apparent expectations regarding the sites and angles of the lines for which the spider was searching. These observations, combined with previous demonstrations of the ability to remember the distance travelled along a radial line, indicate that orb weavers possess the information necessary to form mental representations of their webs. The behavioral phenomena demonstrated here fit Merker's triangular dependency model of animal awareness.

Understanding the temporal dynamics of carnivore assemblages is crucial for clarifying mechanisms of coexistence and co-occurrence and informing conservation planning. The Western polecat Mustela putorius, a medium-sized mustelid of conservation concern, remains poorly studied in terms of activity rhythms, particularly in southern Europe, where its populations are fragmented and declining. In this study, we investigated the temporal activity patterns and spatiotemporal relationships of polecats, assessing whether co-occurrence with other meso-carnivores may shape the species behaviour. Using systematic camera trapping across 35 stations in the northern Apennines in 2024-2025, we obtained 357 independent detections of medium-sized mustelids, including 41 polecats, 127 pine martens, 91 stone martens, and 98 unidentified Martes spp. Activity analyses confirmed significant deviations from random distributions for all species. Polecats and stone martens were predominantly nocturnal, with peak activity in the early night hours, whereas pine martens exhibited greater diurnal patterns, peaking in early morning. Overlap analyses revealed a high temporal overlap between polecats and stone martens, moderate overlap between polecats and pine martens, and intermediate overlap between the two marten species. Polecat activity was strongly influenced by lunar brightness, being concentrated in the darkest nights, whereas martens showed no significant response to moon phases. The Pianka index suggested also limited spatial overlap amongst all species pairs. These results suggest that co-occurrence among the three meso-carnivores at the landscape level may be facilitated primarily by spatial and habitat segregation, with temporal adjustments further reducing direct competition. The occurrence of polecat records mostly on camera traps located around aquatic habitats may explain their rarity in Italian camera-trap datasets and underscores their vulnerability to ongoing wetland loss. Species-level resolution (e.g., distinguishing between the beech marten and the pine marten) is essential to identify habitat segregation as the primary "coexistence" mechanism among mustelids, highlighting the need for species-specific analyses in carnivore community studies, given their markedly different ecological strategies despite phenotypic similarities.

Maternal separation during early life is a well-established model for inducing neurodevelopmental impairments and increasing hippocampal vulnerability. Externally generated mechanosensory stimulation, such as three-dimensional orbital shaking (3D-OS), has been proposed as a candidate modulatory stimulus in cellular and organoid models, but its impact on neonatal brain development under early-life stress conditions remains unknown. We investigated whether 3D-OS, applied as a controlled postnatal mechanosensory stimulation, could partially attenuate behavioural, histological, and molecular alterations induced by maternal separation in rats. Eighteen newborn Sprague Dawley rats were assigned to control (C), maternal separation (MS), or maternal separation plus orbital shaking (MSOS) groups. Maternal separation was performed 3 h/day between postnatal days 2-21; MSOS additionally received 3D-OS (25 rpm, 3 h/day) as a rocking cradle-like mechanosensory stimulation. Behavioural tests (Open Field, Novel Object Recognition, Morris Water Maze, Passive Avoidance), combined with RT-qPCR, Western blot, histology, and immunohistochemistry were conducted. Compared with MS, MSOS rats showed partial improvement in early Morris Water Maze performance and longer step-through latency in the retention phase of Passive Avoidance, whereas Open Field, Novel Object Recognition, and Western blot analyses did not reveal significant inter-group differences. Histological analysis showed reduced neuronal loss and vacuolisation in hippocampal and cortical regions of MSOS rats. RT-qPCR demonstrated reduced hippocampal FGF2 and FGFR1 expression in MS, with values in MSOS shifting toward control levels, whereas immunohistochemistry showed a receptor-specific pattern that was not fully concordant with the transcript data. Early-life 3D-OS administration alleviated maternal separation-induced cognitive decline and structural impairments and modulated hippocampal FGF2-FGFR signalling markers, proposing a neuroprotective effect of externally generated mechanosensory stimulation under early-life stress. These findings provide preclinical evidence that gentle mechanosensory stimulation may support early brain development and mitigate stress-related neurodevelopmental vulnerability.

Understanding the link between bird personality and food preference would help elucidate individual foraging strategies and species adaptability. However, there is a knowledge gap regarding the relationship between personality and food preference to nutritional or energetic quality. Here, we investigated how exploratory behavior, a consistent behavioral trait, influenced the selection of Java sparrows (Lonchura oryzivora) on foods with different nutritional and energetic qualities. We found that food preference varied across fast-, medium-, to slow-exploring groups. The fast- and medium-exploring birds first chose more nutrient-dense millet compared to slow-exploring counterparts. In contrast, with the extension of feeding periods, fast-exploring birds consumed greater quantities of common millet, which is more energy-dense. Furthermore, there was no sexual difference in food preference. These results indicate that exploratory behavioral type is significantly associated with food preference. In particular, fast-exploring Java sparrows exhibited food preferences that were associated with both the nutrient and energy contents of foods, and that such preferences were stage-dependent in the feeding duration. Our findings provide valuable insights into the relationship between personality and food preferences.