Behavioural Processes最新文献

Species of crab have been shown to spatially track and navigate to consequential locations through different processes, such as path integration and landmark orienting. Few investigations examine their ability to wayfind in complex environments, like mazes, with multiple intersections and how they may utilize specific features to benefit this process. Spatial learning potentially would lend a fitness advantage to animals living in complicated habitats, and ghost crab (Ocypode quadrata) is a semiterrestrial species that typically occupies extensive beach environments, which present many navigational challenges. Despite their potential, there are currently no studies that investigate forms of spatial cognition in these animals. To better diversify our knowledge of this trait, the current research exposed ghost crab to a maze with seven intersections. Animals were given multiple trials to learn the location of a reward destination to a specific criterion proficiency. In one condition several landmarks were distributed throughout the maze, and in another the environment was completely empty. Results showed that ghost crab in the landmark present group were able to learn the maze faster, they required significantly fewer trials to reach the learning criterion than those in the landmark absent group. However, only approximately half of the total sample met the learning criterion, indicating the maze was rather difficult. These findings are interpreted through theories of route learning that suggest animals may navigate by establishing landmark-turn associations. Such processes have implications for the cognitive ability of ghost crab, and spatial learning in this species may support the notion of convergent evolution for this trait.

The domestic horse (Equus ferus caballus) makes dung deposits to form “stud-piles” and compulsively examines dung droppings, suggesting that dung contains species-relevant information. The present study investigates horses’ use of location (place), odor (object) and memory for dung sniff encounters. Horses were video recorded in 2 indoor and 4 outdoor riding arenas as they were taken at different time intervals to experimenter-determined objects or dung deposits that they could sniff. Frame-by-frame video analysis measured approaches, sniff duration, nostril use, ear position and blinking associated with dung investigation. Horses approached and sniffed dung-deposits for longer duration than non-dung objects in all test locations. They made head movements across the extent of dung-deposits when sniffing, showed no nostril or ear preference directed to the target, and blinked as they disengage from sniffing. Reduced approach probability and sniff duration showed that they displayed good place/object memory for dung previously visited at similar and different locations on the same day but poor memory for dung visited on a previous day. Adaptive forgetting of object/place memory for dung after a previous day’s dung visit may optimizes risk assessment, including the possibility of premature interruption of foraging by conspecifics.

The interaction of voluntary exercise and housing density on a) anxiety-like behavior and b) the stimulant effects of methamphetamine in C57Bl/6 mice were evaluated. Upon arrival, mice were housed singly or in pairs, and permitted access to home-cage running wheels or not for 4 weeks. Testing for anxiety-like behavior occurred over the next 3 weeks, one test per week [Elevated-Plus Maze (EPM) → Hyponeophagia (HNP) task → Open-Field (OF) task]. The final, OF task involved an 8-hour session in which mice were permitted to explore the chamber (drug free) during Hours 1–3; given an injection (s.c.) of methamphetamine (1.0 mg/kg) after Hour 3; followed by continued behavioral sampling during Hours 4–8. Several tasks (HNP and OF, but not EPM) consistently showed voluntary exercise induced anxiety-like behavior. In addition, two measures (time in center and time resting in the perimeter) in the OF task revealed that exercise mice compared to controls were more responsive to the anxiogenic effects of methamphetamine. Although pair housing was anxiolytic, it did not ameliorate the anxiogenic effects of voluntary exercise. Taken together, these results, when viewed in tandem with previous studies that utilized a less anxious mouse strain (Swiss Webster), may suggest that voluntary exercise is anxiogenic in an anxiety-prone mouse strain such as C57Bl/6 and highlight the importance of considering mouse strain when evaluating the impact of environmental manipulations on anxiety-like behavior in animal models.

It is generally believed that termites can’t learn and are not “intelligent”. This study aimed to test whether termites could have any form of memory. A Y-shaped test device with one release chamber and two identical test chambers was designed and constructed by 3D printing. A colony of damp wood termites was harvested from the wild. Worker termites were randomly selected for experiment. Repellent odors that could mimic the alarm pheromone for termites were first identified. Among all substances tested, a tea tree oil and lemon juice were found to contain repellent odors for the tested termites, as they significantly reduced the time that termites spent in the chamber treated with these substances. As control, a trail pheromone was found to be attractive. Subsequently, a second cohort of termites were operant conditioned by punishment using both tea tree oil and lemon juice, and then tested for their ability to remember the path that could lead to the repellant odors. The test device was thoroughly cleaned between trials. It was found that conditioned termites displayed a reduced tendency to choose the path that led to expectant punishment as compared with naïve termites. Thus, it is concluded that damp wood termites are capable of learning and forming “fear memory”, indicative of “intelligence” in termites. This result challenges established presumption about termites’ intelligence.

Spatial and social cognition are two aspects of fish behaviour that have been subject to an increasing amount of research in recent years, but few have investigated potential behaviour overlaps. Testing the ability for an individual to socially learn a spatial task would bridge this gap in understanding. We provided naïve goldfish, Carassius auratus, the opportunity to observe a trained conspecific navigate a T-shaped maze, and then recorded how many trials it took for them to learn the maze, time taken per trial, motivation, and acceptance of the food reward. We also recorded how many trials it took a control group to learn the maze without the opportunity to observe a demonstrator. The observer group took significantly longer to learn the maze than the control group. Although the observer group were significantly less motivated (trials without a choice made), they were significantly more likely to accept the food reward. The social learning of reward acceptance was taking place, but the process of the demonstration disrupted the training of the spatial task, with possible explanations as the passenger effect and trade-off mechanism being discussed. Future studies are needed to determine whether goldfish can acquire spatial information socially; however, this study contributes to the feasibility of studying social learning of environmentally information in goldfish.

The current study examined the role of stimulus combinations on the repeated assessment of resurgence. Using a within-session resurgence procedure, rats were exposed to different conditions, each with distinct stimulus combinations (AAA, ABA, ABB, ABC and AAB). Two arrangements of stimulus changes were compared: Experiment 1 involved changes in stimulus combinations every five sessions, while Experiment 2 implemented changes every session. Resurgence was observed in both experiments; however, Experiment 2 demonstrated more consistent and repeated resurgence when stimulus combinations changed every session. Notably, the ABA, ABB and ABC conditions showed the highest percentage of sessions in which resurgence was observed. Lastly, the current study extends the application of the within-session resurgence procedure to rats and auditory stimuli, providing a reliable method for assessing resurgence in single subjects under different variable conditions.

Dogs are used for oil detection to support spill remediation and conservation, but little is known about the effects of weathering and aging of oil odorants on dogs’ ability to generalize and discriminate unweathered oil from aged/weathered tar ball oil. Three dogs were trained to detect unweathered oil odorant using a three-alternative choice procedure and automated olfactometers. We evaluated dogs’ ability to discriminate unweathered target oil from four different weathered/tar ball samples. All three dogs successfully discriminated the unweathered target oil from the four nontarget weathered oils with an accuracy of 96%, 97%, and 100%. After the oil discrimination test, dogs’ ability to discriminate unweathered target oil from novel natural odorants on a beach (plastic bottle lid, bird feathers, and rocks) was tested in a novel discrimination test yielding an accuracy of 95%, 100%, and 100%. These data suggest dogs are successful in discriminating unweathered oil from weathered oil with explicit training.

Emotional contagion, a fundamental aspect of empathy, is an automatic and unconscious process in which individuals mimic and synchronize with the emotions of others. Extensively studied in rodents, this phenomenon is mediated through a range of sensory pathways, each contributing distinct insights. The olfactory pathway, marked by two types of pheromones modulated by oxytocin, plays a crucial role in transmitting emotional states. The auditory pathway, involving both squeaks and specific ultrasonic vocalizations, correlates with various emotional states and is essential for expression and communication in rodents. The visual pathway, though less relied upon, encompasses observational motions and facial expressions. The tactile pathway, a more recent focus, underscores the significance of physical interactions such as allogrooming and socio-affective touch in modulating emotional states. This comprehensive review not only highlights plausible neural mechanisms but also poses key questions for future research. It underscores the complexity of multimodal integration in emotional contagion, offering valuable insights for human psychology, neuroscience, animal welfare, and the burgeoning field of animal-human-AI interactions, thereby contributing to the development of a more empathetic intelligent future.

Social hierarchy is a crucial element for survival, reproduction, fitness, and the maintenance of a stable social group in social animals. This study aimed to investigate the physiological indicators, nociception, unfamiliar female mice preference, spatial learning memory, and contextual fear memory of male mice with different social status in the same cage. Our findings revealed significant differences in the trunk temperature and contextual fear memory between winner and loser mice. However, there were no major discrepancies in body weight, random and fasting blood glucose levels, whisker number, frontal and perianal temperature, spleen size, mechanical and thermal pain thresholds, preference for unfamiliar female mice, and spatial memory. In conclusion, social status can affect mice in multiple ways, and, therefore, its influence should be considered when conducting studies using these animals.

Domestic cat (Felis catus) mothers may rely on offspring cries to allocate resources in use of individuals with greater chances for survival and sacrifice the weak ones in case of impossibility to raise the entire large litter. Potential victims of this maternal strategy can enhance their chances of survival, by producing vocalizations with traits mimicking those of higher-quality offspring. We compared acoustic traits of 4990 cries produced during blood sampling by 57 two-week-old captive feral kittens (28 males, 29 females); 47 of them survived to 90 days of age and 10 died by reasons not related to traumas or aggression. No relationship was found between acoustic parameters and kitten survival, however, positive relationship was found between survival and body weight. The cries had moderate cues to individuality and lacked cues to sex. Body weight correlated positively with fundamental frequency and negatively with call rate, duration, peak frequency and power quartiles. We discuss that dishonesty of acoustic traits of kitten quality could develop as adaptation for misleading a mother from allocation resources between the weaker and stronger individuals, thus enhancing individual chances for survival for the weaker littermates. Physical constraint, as body weight, may prevent extensive developing the deceptive vocal traits.