Journal of Comparative Psychology最新文献

Animals can use asocial (e.g., environmental cues) or social (e.g., conspecific behavior) information when making decisions. We investigated decisions made by zebra finches when asocial and social sources conveyed agreeing or conflicting information, and assessed the influence of initial bias on decision making. Finches completed an initial preference test ranking preference for three colors of nest-building material. Birds in the agree group (n = 14) then observed demonstrators build nests using nonpreferred color material (social information) that matched the environment color (asocial information). Birds in the conflict group (n = 15) observed demonstrators build nests with nonpreferred color material that did not match the cage environment (another nonpreferred color). A final preference test assessed any changes in color preference. The agree group reduced average preference for their initially preferred color, but did not significantly increase average preference for the asocial/social colors. The conflict group also reduced average preference for the initially preferred color and also increased preference for the socially demonstrated color. Observers with stronger initial bias were less likely to choose the socially demonstrated color than observers with weaker initial bias. This shows that social information informs nest-building decisions, even when in conflict with asocial information. However, bias influences social information use and adds nuance to how different individuals use information when making decisions. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Dogs are able to cooperate in reciprocal exchange with humans but little is known about the extent of these abilities (Range & Virányi, 2015). In the Still Face paradigm, infants reply to a sudden nonreciprocal facial expression with gaze aversion and an increase in re-engagement and distress behaviors (E. Tronick et al., 1978). We directly adapted this method; the dog's owner talked to the dog, then abruptly switched to a still, neutral face, maintaining eye contact. In Study 1 (N = 20), we found that dogs showed a significant decrease in the amount of looking at the owner in the Still Face phase, paralleling the results found in gaze aversion in infants, and they performed fewer pawing and vocalizations toward the person in the Still Face phase. In Study 2 (N = 60), we included one condition of continuous physical contact, and one condition that was a direct replication of the initial study without physical contact. Similar to human infants, we found a significant decrease in looking from the Interaction phase to the Still Face phase. However, in contrast to human infants, re-engagement and stress behaviors were higher in the Interaction phase than the Still Face phase. Looking and re-engagement behaviors differed based on the condition, with a smaller difference between phases in the Petting condition. These results suggest that dogs are capable of perceiving these small changes in human affect. However, unlike human infants, dogs seem to have greater expectations about physical interactions than verbal interactions, as they reacted more strongly to an Interaction phase without physical contact than the Still Face. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Delay of gratification and inhibitory control are generally considered measures of self-control. In humans, individual differences in measures of self-control are associated with a host of behavioral, neurological, cognitive, and health-related outcomes. Self-control is not unique to humans and has been demonstrated in a variety of nonhuman species using a variety of paradigms. In this study, the effect of sex and age on delay of gratification performance, as measured by the hybrid delay task, was tested in a sample of 88 chimpanzees. Additionally, whether individual differences in hybrid delay task performance were associated with different aspects of personality was examined in this study. Contrary to reports in human subjects, geriatric male chimpanzees were found to perform more efficiently than adult males, while no age differences were found between geriatric and adult females. Indeed, delay of gratification efficiency was positively associated with age in males and negatively associated with age in females. Chimpanzees that performed more efficiently on the hybrid delay task were also found to be rated as more intelligent, more extraverted, and less impulsive. These findings suggest that objective measures of efficiency in delay of gratification tasks are associated with different dimensions of personality, which have some overlapping construct validity. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Exploratory behaviors describe the actions performed by an animal to obtain information on an object, environment, or individual by using its different senses. Exploration is described in some marine mammals, but not yet in manatees. Our study investigated behavioral and acoustic responses of two groups of Antillean manatees (N = 12 and N = 4) housed in zoological parks toward various stimuli involving three sensory modalities: visual, tactile, and auditory. Simultaneous audio and video recordings were collected during three periods of time (i.e., before, during, and after the presentation of all stimuli). Behaviors related to interest, social behaviors, the number and type of calls produced, and their frequency and duration were recorded and analyzed. Manatees reacted more to submerged stimuli than to out-of-water and sound stimuli, with an increase in approach, social contacts, and number of vocalizations. The proportion of squeaks and squeals call types also varied according to stimuli, and call entropy and F0 range varied according to periods. Our results suggest that manatees display sensory preferences when exploring stimuli, with more interest in manipulable stimuli, supporting the importance of their somatic perception. We highlight the need for particular enrichment programs (i.e., involving submerged objects) in zoological facilities. By displaying social contacts and by producing vocalizations, manatees communicate information such as their motivational state. The increase in call rate, harsh calls, and entropy values could be valid indicators of heightened arousal. We encourage further studies to associate acoustic recordings with ethological data collection to increase the understanding of manatees' behaviors andperception. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

When making decisions, humans often strive to uphold objective, absolute standards, such as about what is small versus large, blue versus purple, or unfair versus fair, suggesting that our judgments should not be swayed by extraneous factors such as the sequence or frequency of events to be judged. Yet in previous research, when some items (e.g., threatening faces) became less frequent, humans responded by expanding their concept (of "threatening") to include more ambiguous stimuli. We assessed the origins of this perceptual frequency bias by testing 25 capuchins, seven rhesus monkeys, and 102 humans on a computer task in which they had to classify one circle at a time (pulled from a continuum of 50 circle sizes) as either small or large. Small and large circles initially appeared with equal probability but over time small circles either became less frequent, more frequent, or did not change in frequency. All three species showed changes in judgment, but contrary to predictions, they contracted, rather than expanded, their size judgments of the less frequent category. In other words, when small circles became rare, participants were more likely to judge ambiguous circles sizes as large (and vice versa). This may have been due to the immediate explicit feedback, as has recently been found in humans, and we consider possible mechanisms driving our participants' responses. These results suggest that humans' difficulties in maintaining absolute standards are shared with other animals. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

A growing body of research demonstrates that humans can accurately perceive the emotional states of animals solely by listening to their calls, highlighting shared evolutionary ancestry. Yet, the cognitive and perceptual mechanisms underlying heterospecific emotion perception have remained open to investigation. One hypothesis is that humans rely on simple acoustic heuristics to make such judgments, for example, perceiving higher-pitched calls as reflecting heightened emotional arousal (the "pitch rule"). This could lead to accurate judgments of emotion since in most mammals, as in humans, vocal fundamental frequency (the acoustic determinant of the pitch percept) does objectively correlate with emotional arousal. In the present study, we used digital pitch manipulation to create pairs of animal calls that were perceptually identical except for pitch, and we measured human perceptions of the caller's emotional arousal using an online survey. Calls of six phylogenetically diverse species were included as stimuli. Participants attributed slightly but statistically significantly higher arousal to higher-pitched versions of the same calls. Variation in application of the pitch rule across species was not well explained by familiarity, and prior experience with cats did not significantly predict sensitivity to pitch in cat vocalizations. Cross-species variation also did not align with phylogenetic distance from humans, or the hypothetical usefulness of pitch for making accurate judgments. Thus, the pitch rule may be a "mammalomorphic" heuristic leading to accurate emotion judgments in some taxa and call types and erroneous judgments in others, depending in part on phylogenetic distance and the mechanisms of call production. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Goodyear and Kamil (2004) assessed the ability of Clark's nutcrackers to find buried food based on a cross-shaped array of landmarks at different distances from the goal. Their findings suggested that proximal landmarks overshadowed learning about distal landmarks, and this was attenuated when assessing the effect of distal landmarks on learning about proximal landmarks. In this study, we aimed to replicate their findings in human spatial navigation by using a virtual environment. Three groups of participants were trained in an open environment featuring orientation cues, and they had to find a hidden goal with reference to four landmarks that were arranged in the shape of a cross and placed at different distances from the goal. Two of the four landmark distances were common across all three groups to allow a comparison of the extent of overshadowing under comparable conditions. Following training, all participants were tested with each of the four landmarks individually. Consistent with the results in birds, we observed better performance in the groups with more distal landmarks, suggesting that overshadowing was greater in the groups with closer landmarks and thus dependent on the spatial distance between the landmarks and the goal. Landmarks near the goal more effectively overshadowed landmarks far from the goal. A second experiment, in which landmarks and orientation cues were misaligned in order to prevent the use of a straightforward solution to the task, replicated the results. The results are discussed in terms of a modification of Pearce's configural model. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Black-capped chickadees (Poecile atricapillus) and other species that feed at bird feeders balance the benefit of easy foraging with the added risk of predation. Individual birds respond differently to risky situations, and these differences have been attributed to the birds' personalities, which researchers commonly assess with an "open-field" behavioral assay. However, these behavioral assays in birds have not been compared to behavior in the wild in the context of foraging in the presence of a predator (i.e., risk-taking behavior). We color-banded chickadees in a wild population and conducted behavioral assays in the field. We later used foraging trials to investigate these color-banded individuals' responses to a predator (Cooper's hawk, Accipiter cooperii) model or a series of Cooper's hawk calls. We found that foraging black-capped chickadees responded more strongly to the presence of a predator model than to predator calls. Individual birds differed in their responses, and the behavioral assays (activity and exploration) predicted individual behavior in the wild during the foraging experiments. Activity and exploration assay scores were only weakly related, suggesting these two assays represent different traits. Both highly active birds and fast explorers exhibited some reluctance to visit the feeder (either reduced number of visits or greater latency to visit) when the predator model was present, a relationship that was somewhat unexpected. Our results suggest that standard behavioral assays predict behavior in the wild, but care should be taken when generalizing among species and studies. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Many animals, including humans, must make decisions when outcomes involve risk and/or ambiguity. To explore the evolutionary roots of decision making when outcomes are unknown, we modified the Balloon Analogue Risk Task (BART) for use with tufted capuchin monkeys (Sapajus [Cebus] apella), creating the Primate Analogue Risk Task (PART). Using both the BART and the PART, we first compared human performance across the two tasks using analogous parameters. Humans' performance on the two tasks was positively correlated. Next, we tested capuchin monkeys' performance on the PART to assess their decision-making strategies in the context of ambiguity. Secondarily, although it was not the main goal of the study, this allowed us to look at species differences between capuchins' and humans' performance. Finally, we investigated the influence of prior experience on human and capuchin decision-making behavior. Neither capuchins nor humans behaved differently following an unsuccessful trial compared to a successful trial. We found individual differences in capuchin monkeys' choice behavior, though as a whole they demonstrated a pattern of reward maximization over time. Finally, as a species, capuchins had lower PART risk scores than humans. This paradigm presents a useful way to assess behavior in a context with uncertain outcomes using a comparative approach. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Comments on an article by Jay W. Schwartz , Kayleigh H. Pierson, and Alexander K. Reece (see record 2024-19488-001). In this issue, Schwartz et al. (2024) tackle the pitch rule in humans by testing to what extent we use pitch alone to judge emotional arousal across closely and distantly related animal species. The findings of Schwartz et al. open a number of intriguing possibilities for future research: Notably important additional steps would include to further investigate the accuracy of the pitch rule across closely and distantly related species. Upon this, in order to study the evolutionary ancestry of the pitch rule, it will be necessary to study its applicability across nonhumans. Particularly interesting would be the inclusion of subject species that have been found to eavesdrop on heterospecific alarm calls. Previous research (see Hoeschele, 2017 for a review) as well as present findings on human ratings of macaque versus cricket calls also suggest that we should additionally focus on sound features that compliment emotional arousal rating beyond pitch such as spectral information. (PsycInfo Database Record (c) 2024 APA, all rights reserved).