Observational learning from tool using models by human-reared and mother-reared capuchin monkeys (<Emphasis Type="Italic">Cebus apella</Emphasis>)

Studies of wild capuchins suggest an important role for social learning, but experiments with captive subjects have generally not supported this. Here we report social learning in two quite different populations of capuchin monkeys (Cebus apella). In experiment 1, human-raised monkeys observed a familiar human model open a foraging box using a tool in one of two alternative ways: levering versus poking. In experiment 2, mother-raised monkeys viewed similar techniques demonstrated by monkey models. A control group in each population saw no model. In both experiments, independent coders detected which technique experimental subjects had seen, thus confirming social learning. Further analyses examined fidelity of copying at three levels of resolution. The human-raised monkeys exhibited fidelity at the highest level, the specific tool use technique witnessed. The lever technique was seen only in monkeys exposed to a levering model, by contrast with controls and those witnessing poke. Mother-reared monkeys instead typically ignored the tool and exhibited fidelity at a lower level, tending only to re-create whichever result the model had achieved by either levering or poking. Nevertheless this level of social learning was associated with significantly greater levels of success in monkeys witnessing a model than in controls, an effect absent in the human-reared population. Results in both populations are consistent with a process of canalization of the repertoire in the direction of the approach witnessed, producing a narrower, socially shaped behavioural profile than among controls who saw no model. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Comparing responses to novel objects in wild baboons (<Emphasis Type="Italic">Papio ursinus</Emphasis>) and geladas (<Emphasis Type="Italic">Theropithecus gelada</Emphasis>)

Behavioral flexibility is considered by some to be one of the hallmarks of advanced cognitive ability. One measure of behavioral flexibility is how subjects respond to novel objects. Despite growing interest in comparative cognition, no comparative research on neophilia in wild primates has been conducted. Here, we compare responses to novel objects in wild chacma baboons (Papio ursinus) and geladas (Theropithecus gelada). Baboons and geladas are closely related taxa, yet they differ in their ecology and degree of social tolerance: (1) baboons are habitat and dietary generalists, whereas geladas have one of the most specialized primate diets (90% grass); (2) baboons exhibit an aversion toward extra-group individuals, whereas geladas typically exhibit an attraction toward them. Using subjects of all age and sex classes, we examined responses to three different objects: a plastic doll, a rubber ball, and a metal can. Overall, baboon subjects exhibited stronger responses to the objects (greater neophilia and exploration) than gelada subjects, yet we found no evidence that the geladas were afraid of the objects. Furthermore, baboons interacted with the objects in the same way they might interact with a potential food item. Responses were unrelated to sex, but immatures showed more object exploration than adults. Results corroborate novel object research conducted in captive populations and suggest that baboons and geladas have differences in behavioral flexibility (at least in this cognitive domain) that have been shaped by ecological (rather than social) differences between the two species. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Transport of tools to food sites in tufted capuchin monkeys (<Emphasis Type="Italic">Cebus apella</Emphasis>)

Tool use and transport represent cognitively important aspects of early hominid evolution, and nonhuman primates are often used as models to examine the cognitive, ecological, morphological and social correlates of these behaviors in order to gain insights into the behavior of our early human ancestors. In 2001, Jalles-Filho et al. found that free-ranging capuchin monkeys failed to transport tools (stones) to food sites (nuts), but transported the foods to the tool sites. This result cast doubt on the usefulness of Cebus to model early human tool-using behavior. In this study, we examined the performance of six captive tufted capuchin monkeys (Cebus apella) in a tool transport task. Subjects were provided with the opportunity to transport two different tools to fixed food reward sites when the food reward was visible from the tool site and when the food reward was not visible from the tool site. We found that the subjects quickly and readily transported probing tools to an apparatus baited with syrup, but rarely transported stones to a nut-cracking apparatus. We suggest that the performance of the capuchins here reflects an efficient foraging strategy, in terms of energy return, among wild Cebus monkeys.     

Comorbid Problems in ADHD: Degree of Association,Shared Endophenotypes,and Formation of Distinct Subtypes. Implications for a Future <Emphasis Type="Italic">DSM</Emphasis>

We aimed to assess which comorbid problems (oppositional defiant behaviors, anxiety, autistic traits, motor coordination problems, and reading problems) were most associated with Attention-Deficit/Hyperactivity Disorder (ADHD); to determine whether these comorbid problems shared executive and motor problems on an endophenotype level with ADHD; and to determine whether executive functioning (EF)—and motor-endophenotypes supported the hypothesis that ADHD with comorbid problems is a qualitatively different phenotype than ADHD without comorbid problems. An EF—and a motor-endophenotype were formed based on nine neuropsychological tasks administered to 816 children from ADHD—and control-families. Additional data on comorbid problems were gathered using questionnaires. Results indicated that oppositional defiant behaviors appeared the most important comorbid problems of ADHD, followed by autistic traits, and than followed by motor coordination problems, anxiety, and reading problems. Both the EF—and motor-endophenotype were correlated and cross-correlated in siblings to autistic traits, motor coordination problems and reading problems, suggesting ADHD and these comorbid problems may possibly share familial/genetic EF and motor deficits. No such results were found for oppositional defiant behaviors and anxiety. ADHD in co-occurrence with comorbid problems may not be best seen as a distinct subtype of ADHD, but further research is warranted. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Do captive mandrills invent new gestures?

Studies of intraspecific behavioral variability have documented cases where behaviors are present in some populations or groups but are absent in others. In some cases these differences cannot be explained by recourse to environmental or genetic variation, and may instead represent “traditions”. Despite many examples of animal traditions in acoustic communication, relatively few examples exist of gestural traditions. Here I report on a study of communication across eight captive groups of mandrills (Mandrillus sphinx) in which a prominent gesture (Hand extension) was unique to two groups. Habitat variability, genetic differences, and sampling bias were not sufficient to account for the gesture’s limited distribution across the study groups. Within the two groups where the gesture did occur only the juveniles in the group performed it, consistently directing it toward adults. Quantitative analysis of the contexts and responses associated with the gesture suggested that juveniles utilized it to provoke adults. Moreover, the gesture appeared to minimize the risk juveniles incurred while inciting adults, suggesting that repeated social interactions shaped the gesture’s form. Interestingly, both the groups where the gesture emerged contained few juveniles. With limited play partners, these juveniles may have resorted to harassing adults as an alternative social play outlet. The creation of this novel gesture may thus be due to the combined influence of a shortage of play partners and of the increased free time for playful social exploration afforded by captivity. Although juveniles frequently “eavesdropped” on dyadic interactions involving the gesture and would subsequently initiate an interaction with the recipient of the gesture, there was no definitive evidence for social transmission; the gesture could instead have been independently invented by each juvenile. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Conformism in the food processing techniques of white-faced capuchin monkeys (Cebus capucinus)

Researchers of “culture” have long been interested in the role of social learning in establishing patterns of behavioral variation in wild animals, but very few studies examine this issue using a developmental approach. This 7-year study examines the acquisition of techniques used to process Luehea candida fruits in a wild population of white-faced capuchin monkeys, Cebus capucinus, residing in and near Lomas Barbudal Biological Reserve, Costa Rica. The two techniques for extracting seeds (pounding or scrubbing) were approximately equal in efficiency, and subjects experimented with both techniques before settling on one technique—typically the one they most frequently observed. In a sample of 106 subjects that had already settled on a preferred technique, the females adopted the maternal technique significantly more often than expected by chance, but the males did not. Using a longitudinal approach, I examined the acquisition of Luehea processing techniques during the first 5 years of life. Regression analysis revealed that the technique most frequently observed (measured as proportion of Luehea processing bouts observed that used pounding as opposed to scrubbing) significantly predicted the technique adopted by female observers, particularly in the second year of life; the amount of impact of the observed technique on the practiced technique was somewhat less significant for male observers. These results held true for (a) observations of maternal technique only, (b) observations of technique used by all individuals other than the mother, and (c) observations of maternal and non-maternal techniques combined. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Three-Valued Temporal Logic <Emphasis Type="Italic">Q</Emphasis><Subscript><Emphasis Type="Italic">t</Emphasis></Subscript> and Future Contingents

Prior’s three-valued modal logic Q was developed as a philosophically interesting modal logic. Thus, we should be able to modify Q as a temporal logic. Although a temporal version of Q was suggested by Prior, the subject has not been fully explored in the literature. In this paper, we develop a three-valued temporal logic Q _t and give its axiomatization and semantics. We also argue that Q _t provides a smooth solution to the problem of future contingents. Presented by Daniele Mundici     

Development of interception of moving targets by chimpanzees (<Emphasis Type="Italic">Pan troglodytes</Emphasis>) in an automated task

The experiments investigated how two adult captive chimpanzees learned to navigate in an automated interception task. They had to capture a visual target that moved predictably on a touch monitor. The aim of the study was to determine the learning stages that led to an efficient strategy of intercepting the target. The chimpanzees had prior training in moving a finger on a touch monitor and were exposed to the interception task without any explicit training. With a finger the subject could move a small "ball" at any speed on the screen toward a visual target that moved at a fixed speed either back and forth in a linear path or around the edge of the screen in a rectangular pattern. Initial ball and target locations varied from trial to trial. The subjects received a small fruit reinforcement when they hit the target with the ball. The speed of target movement was increased across training stages up to 38 cm/s. Learning progressed from merely chasing the target to intercepting the target by moving the ball to a point on the screen that coincided with arrival of the target at that point. Performance improvement consisted of reduction in redundancy of the movement path and reduction in the time to target interception. Analysis of the finger's movement path showed that the subjects anticipated the target's movement even before it began to move. Thus, the subjects learned to use the target's initial resting location at trial onset as a predictive signal for where the target would later be when it began moving. During probe trials, where the target unpredictably remained stationary throughout the trial, the subjects first moved the ball in anticipation of expected target movement and then corrected the movement to steer the ball to the resting target. Anticipatory ball movement in probe trials with novel ball and target locations (tested for one subject) showed generalized interception beyond the trained ball and target locations. The experiments illustrate in a laboratory setting the development of a highly complex and adaptive motor performance that resembles navigational skills seen in natural settings where predators intercept the path of moving prey. Electronic Supplementary Material Supplementary material is available for this article if you access the article at . A link in the frame on the left on that page takes you directly to the supplementary material.     

Spatial memory in the grey mouse lemur (Microcebus murinus)

Wild animals face the challenge of locating feeding sites distributed across broad spatial and temporal scales. Spatial memory allows animals to find a goal, such as a productive feeding patch, even when there are no goal-specific sensory cues available. Because there is little experimental information on learning and memory capabilities in free-ranging primates, the aim of this study was to test whether grey mouse lemurs (Microcebus murinus), as short-term dietary specialists, rely on spatial memory in relocating productive feeding sites. In addition, we asked what kind of spatial representation might underlie their orientation in their natural environment. Using an experimental approach, we set eight radio-collared grey mouse lemurs a memory task by confronting them with two different spatial patterns of baited and non-baited artificial feeding stations under exclusion of sensory cues. Positional data were recorded by focal animal observations within a grid system of small foot trails. A change in the baiting pattern revealed that grey mouse lemurs primarily used spatial cues to relocate baited feeding stations and that they were able to rapidly learn a new spatial arrangement. Spatially concentrated, non-random movements revealed preliminary evidence for a route-based restriction in mouse lemur space; during a subsequent release experiment, however, we found high travel efficiency in directed movements. We therefore propose that mouse lemur spatial memory is based on some kind of mental representation that is more detailed than a route-based network map. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

The parallel-less Poggendorff: Virtual contours put the illusion down but not out

Four versions of Poggendorff displays were compared: (1) the conventional display of a transversal interrupted by parallel lines, (2) a transversals-only display, (3) a virtual-contour display where the parallels were suggested (but not drawn) via “good continuation” and “c1osure, ” and (4) the profile display, a degraded version of the virtual-contour display that retained many of its borders but did not suggest parallels. Each display was drawn with transversal tilted at 45 and 51 deg from vertical. All displays produced significant illusions at both tilts. By comparison with the illusion magnitudes of the conventional display, the effects for the other displays were small. The outcome supports the existence of two salient illusion-producing factors: the necessity for actual contours to form the subtended angle and assimilation of the transversal toward O’s horizontal.     

Who do you trust? The impact of facial emotion and behaviour on decision making

During social interactions, we use available information to guide our decisions, including behaviour and emotional displays. In some situations, behaviour and emotional displays may be incongruent, complicating decision making. This study had two main aims: first, to investigate the independent contributions of behaviour and facial displays of emotion on decisions to trust, and, second, to examine what happens when the information being signalled by a facial display is incongruent with behaviour. Participants played a modified version of the Trust Game in which they learned simulated players’ behaviour with or without concurrent displays of facial emotion. Results indicated that displays of anger, but not happiness, influenced decisions to trust during initial encounters. Over the course of repeated interactions, however, emotional displays consistent with an established pattern of behaviour made independent contributions to decision making, strengthening decisions to trust. When facial display and behaviour were incongruent, participants used current behaviour to inform decision making.     

Diversity in agonistic behavior of croaking gouramis (Trichopsis vittata,T. schalleri,and T. pumila; Anabantoidei) and the paradise fish (Macropodus opercularis; Anabantoidei)

Agonistic encounters of all three species of the vocalizing genus Trichopsis were observed in order to compare species-specific fighting strategies and the specific investment in acoustics. Additionally, these encounters were compared to agonistic encounters of Macropodus opercularis which was considered to be mute. The aim of this comparison was to investigate if mute fishes stress visual or tactile displays. Within the genus Trichopsis, significant differences among the three species were found in qualitative and quantitative analysis of displays. Frontal display occurred only in Trichopsis vittata, whereas a strong tail-beating while vocalizing was only observed in Trichopsis pumila. Fight duration and the number of sounds and circlings were highest in Trichopsis schalleri. The largest relative distances between circling opponents occurred in T. pumila, the smallest species. Also, the number of attacks was lowest in T. pumila. Fighting assessment seemed to be different in each species. For the first time, sound production has been reported for Macropodus opercularis (infrequently and with extreme low sound pressure levels), but much more investment in visual and tactile displays has been demonstrated. Lowering the branchiostegal membrane and spreading the opercula occurred only in M. opercularis and was never observed in any of the Trichopsis species. The number of attacks was higher in Macropodus than in any Trichopsis species. The relative distance between Macropodus opponents while circling was closest compared to the three Trichopsis species. Visual and contact displays are reduced in extensively vocalizing fish species, like Trichopsis sp., compared to mute or seldom vocalizing species, like Macropodus. © 1996 Wiley-Liss, Inc.     

中国哲学中身心关系的几种形态

Ancient Chinese philosophers were inclined to preserve the doctrine of a unified body and mind rather than to engage in a discussion on the separation of the two. In addition, most traditional Chinese philosophers stressing in particular the function of mind. Based on the tradition of believing in the concept of qi, they traced the cause of their spiritual activities to the natural effect of the qi. The modalities display a phenomenological characteristic that looks at mental activities lightly, and examines language and action as a natural revelation of material force, qi. __________ Translated from Beijing Daxue Xuebao 北京大学学报 (Journal of Peking University), 2005, (5): 5–14     

Modern views on motor skill learning are not ‘representative’!

Approaches to the explanation of (motor) behaviour deriving from basic Cybernetic principles are contrasted with that based on Skinner's principle of operant conditioning. The reliance of the former on systems of representation (comparators, transducers, schemas etc.), not open to observation, is shown to give rise to a number of theoretical and applied problems. While Skinner's approach is shown to avoid such assumptions it is, in turn, limited in the explanations it provides for behavioural change by its undue emphasis on why things are done at the expense of how they are done. It is argued that recent developments in Ecological Psychology, particularly dynamical systems approaches, provide novel solutions to the question of how things are done but, in so doing, lose track of the why. In spite of the limitations of either perspective on its own, there does seem to be sufficient (fundamental) communality and complementarity to provide the basis for a rapprochement that can lead to a better understanding of behaviour in general and motor behaviour in particular.     

Views On Happiness In The Television Series <Emphasis Type="Italic">Ally Mcbeal</Emphasis>: The Philosophy Of David E Kelley

This article contributes to our understanding of popular thinking about happiness by exploring the work of David E Kelley, the creator of the television program Ally McBeal and an important philosopher of happiness. Kelley's major points are as follows. He is more ambivalent than is generally the case in popular philosophy about many of the traditional sources of happiness. In regard to the maxim that money can't buy happiness he gives space to characters who assert that there is a relationship between material comfort and happiness, as well as to those that claim the opposite position. He is similarly ambivalent about the relationship between loving relationships and happiness; and friendships and happiness. In relation to these points Kelley is surprisingly principled in citing the sources that he draws upon in his thinking (through intertextual references to genres and texts that have explored these points before him). His most original and interesting contributions to popular discussions of the nature of happiness are twofold. The first is his suggestion that there is a lot to be said for false consciousness. He presents situations where characters choose wilfully to ignore reality and instead to live in fantasy worlds where they are happy. Rather than condemning such behaviour, Kelley presents it as understandable, attractive and perhaps even heroic. The second is his proposal that happiness should be seen as an effect of bodily performance rather than an expression of the authentic inner self -- if one forces oneself to smile, happiness may follow. Ultimately Ally McBeal presents a multifaceted popular account of the nature of happiness, where the various positions explored cannot all be reconciled; and where ironic ambivalence is the key tone.     

Spontaneous social orienting and gaze following in ringtailed lemurs (<Emphasis Type="Italic">Lemur catta</Emphasis>)

Both human and nonhuman primates preferentially orient toward other individuals and follow gaze in controlled environments. Precisely where any animal looks during natural behavior, however, remains unknown. We used a novel telemetric gaze-tracking system to record orienting behavior of ringtailed lemurs (Lemur catta) interacting with a naturalistic environment. We here provide the first evidence that ringtailed lemurs, group-living prosimian primates, preferentially gaze towards other individuals and, moreover, follow other lemurs’ gaze while freely moving and interacting in naturalistic social and ecological environments. Our results support the hypothesis that stem primates were capable of orienting toward and following the attention of other individuals. Such abilities may have enabled the evolution of more complex social behavior and cognition, including theory of mind and language, which require spontaneous attention sharing. This is the first study to use telemetric eye-tracking to quantitatively monitor gaze in any nonhuman animal during locomotion, feeding, and social interaction. Moreover, this is the first demonstration of gaze following by a prosimian primate and the first to report gaze following during spontaneous interaction in naturalistic social environments. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Elemental and non-elemental olfactory learning in Drosophila

Brain complexity varies across many orders of magnitude between animals, and it is often assumed that complexity underpins cognition. It is thus important to explore the cognitive capacity of widely used model organisms such as Drosophila. We systematically investigated the fly’s ability to learn discriminations involving compound olfactory stimuli associated with shock. Flies could distinguish binary mixtures (AB+ CD-), including overlapping mixtures (AB+ BC-). They could learn positive patterning (AB+ A- B-) but could not learn negative patterning (A+ B+ AB-) or solve a biconditional discrimination task (AB+ CD+ AC- BD-). Learning about the elements of a compound (AB+) was not affected by prior conditioning of one of the elements (A+ AB+): flies do not exhibit blocking in this task. We compare these results with the predictions from simulation of several well-known theoretical models of learning, and find none are fully consistent with the overall pattern of observed behaviour.     

<Emphasis Type="Italic">Ziran</Emphasis> and <Emphasis Type="Italic">Wuwei</Emphasis> in the <Emphasis Type="Italic">Daodejing</Emphasis>: An Ethical Assessment

In Daoist philosophy, the self is understood as an individual interdependent with others, and situated within a broader environment. Within this framework, the concept ziran is frequently understood in terms of naturalness or nature while wuwei is explained in terms of non-oppressive government. In many existing accounts, little is done to connect these two key Daoist concepts. Here, I suggest that wuwei and ziran are correlated, ethical, concepts. Together, they provide a unifying ethical framework for understanding the philosophy of the Daodejing. I explore the meaning of ziran as self-so-ness or, in human terms, as pertaining to an individual’s spontaneity. The appropriate response to the spontaneity of individuals is to avoid, insofar as possible, imposing or using restrictive norms and methods, that is, wuwei. According to this view, ziran and wuwei offer an account of ethics that attends to core notions of interdependent selfhood, including mutuality, relationality, interdependence, symbiosis, and responsiveness.     

Mental representation of symbols as revealed by vocabulary errors in two bonobos (<Emphasis Type="Italic">Pan paniscus</Emphasis>)

Error analysis has been used in humans to detect implicit representations and categories in language use. The present study utilizes the same technique to report on mental representations and categories in symbol use from two bonobos (Pan paniscus). These bonobos have been shown in published reports to comprehend English at the level of a two-and-a-half year old child and to use a keyboard with over 200 visuographic symbols (lexigrams). In this study, vocabulary test errors from over 10 years of data revealed auditory, visual, and spatio-temporal generalizations (errors were more likely items that looked like sounded like, or were frequently associated with the sample item in space or in time), as well as hierarchical and conceptual categorizations. These error data, like those of humans, are a result of spontaneous responding rather than specific training and do not solely depend upon the sample mode (e.g. auditory similarity errors are not universally more frequent with an English sample, nor were visual similarity errors universally more frequent with a photograph sample). However, unlike humans, these bonobos do not make errors based on syntactical confusions (e.g. confusing semantically unrelated nouns), suggesting that they may not separate syntactical and semantic information. These data suggest that apes spontaneously create a complex, hierarchical, web of representations when exposed to a symbol system. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.