Case study of a one‐sided attack by multiple troop members on a nontroop adolescent male and the death of Japanese macaques (Macaca fuscata)

An adolescent wild male Japanese macaque (Macaca fuscata), following Kinkazan A troop, was attacked one‐sidedly by multiple members of the troop. The victim was identified as PI, and was estimated to be seven±one year old. The aggressive interaction was recorded by video camera until the end. Although at least 16 troop members approached PI more than once, only three males (one adult, two adolescents) of A troop attacked him. PI kept crouching throughout the attack, then escaped to the shore and dived into the sea. The interaction continued for more than one hour. PI was found dead a few hours after the end of interaction. The damage caused by the assailants was not the direct cause of PI's death; it was due to hypothermia caused by drifting in the sea. PI's life history was reconstructed from past records. PI was a normal adolescent male who migrated from an all‐male group around B₁ troop and started ranging around A troop. The aggressive interaction is believed to be a typical example of conflict between troop males and a nontroop male. The interaction period was very long compared with previous reports on such conflicts among Japanese macaques. PI kept crouching in open areas, exposing himself as a potential competitor for the resources of the troop, and did not show any submissive or reconciliatory behavior toward the troop males. This may be why the troop males did not stop the attack. Aggr. Behav. 35:334–341, 2009. © 2009 Wiley‐Liss, Inc.     

Social learning in juvenile lemon sharks, Negaprion brevirostris

Social learning is taxonomically widespread and can provide distinct behavioural advantages, such as in finding food or avoiding predators more efficiently. Although extensively studied in bony fishes, no such empirical evidence exists for cartilaginous fishes. Our aim in this study was to experimentally investigate the social learning capabilities of juvenile lemon sharks, Negaprion brevirostris. We designed a novel food task, where sharks were required to enter a start zone and subsequently make physical contact with a target in order to receive a food reward. Naive sharks were then able to interact with and observe (a) pre-trained sharks, that is, ‘demonstrators’, or (b) sharks with no previous experience, that is, ‘sham demonstrators’. On completion, observer sharks were then isolated and tested individually in a similar task. During the exposure phase observers paired with ‘demonstrator’ sharks performed a greater number of task-related behaviours and made significantly more transitions from the start zone to the target, than observers paired with ‘sham demonstrators’. When tested in isolation, observers previously paired with ‘demonstrator’ sharks completed a greater number of trials and made contact with the target significantly more often than observers previously paired with ‘sham demonstrators’. Such experience also tended to result in faster overall task performance. These results indicate that juvenile lemon sharks, like numerous other animals, are capable of using socially derived information to learn about novel features in their environment. The results likely have important implications for behavioural processes, ecotourism and fisheries.     

The Shroud of Turin: A Historiographical Approach

Criteria of historical assessment are applied to the Turin Shroud to determine which hypothesis relating to the image formation process is the most likely. To implement this, a ‘Minimal Facts’ approach is followed that takes into account only physicochemical and historical data receiving the widest consensus among contemporary scientists. The result indicates that the probability of the Shroud of Turin being the real shroud of Jesus of Nazareth is very high; historians and natural theologians should therefore pay it increased attention.     

Slower Reorientation of Trunk for Reactive Turning while Walking in Hemiparesis Stroke Patients

We examined the behavioral characteristics of reactive turning in hemiplegic stroke patients when they were informed of the turning direction just before turning was required at an unpredictable time. Eleven stroke patients and 20 healthy elderly control people were asked to initiate a turn as soon as a visual cue to inform them of the turning direction was activated unpredictably using a foot switch. Both the segmental reorientation and stepping type when turning 90° while walking were measured. The results indicated preserved segmental reorientation of the head and pelvis in stroke patients. Stroke patients showed delays in pelvic turning but not in head turning. Their delayed pelvic movement might be due to motor dysfunction and the time taken to ensure stability when deciding when to turn.     

Variable coordination of eye and head movements during the early development of attention: A longitudinal study of infants aged 12–36 months

This longitudinal study investigated the effects of attentional development on peripheral stimulus localization by analyzing the eye and head movements of toddlers as they matured from 12 to 36 months. On each trial of an experiment, a central fixation point and a 30° peripheral stimulus were presented, such that in the gap condition the fixation disappeared 300 ms before the peripheral stimulus, whereas in the no-overlap condition it disappeared simultaneously as the peripheral stimulus, and in the overlap condition the fixation remained present when the peripheral target occurred. Results showed that eye and head movement latencies were highly correlated in all conditions and ages. However, at 12 months, head movements were as fast as eye movements, whereas during the subsequent development, eye movements became increasingly faster than head movements. These findings are indicative of a transition between 12 and 36 months due either to a change in attentional control, or to changes in the size of the visual field in which only eye movements occur.     

Individual differences in disengagement of fixation and temperament: Longitudinal research on toddlers

It has been suggested that a shift occurs in the brain's control system from the orienting network in infancy to the executive network by the age of 3–4 years; however, there has been little empirical evidence of this shift during toddlerhood. Therefore, the present study examined how the orienting system in infancy is related to an effortful control system at a later age. Children were assessed longitudinally at 12, 18, 24, and 36 months of age, using a gap-overlap task in which dynamic geometrical-shape stimuli were presented. Parents completed temperament questionnaires about the children at each age. A delayed-gratification task was also given to 36-month-olds. Overall, saccadic latencies in the gap-overlap task were significantly faster at 36 months. At all ages, responses were slower during overlap trials than during gap or no-overlap trials. Longer latencies in the overlap condition were associated with low temperamental orienting/regulation scores at 12 months but with high effortful control scores at 18 and 24 months. The associations at 18 and 24 months are thought to represent a genuine positive association between effortful control and sustained and focused attention.     

Theorema: Towards computer-aided mathematical theory exploration

Theorema is a project that aims at supporting the entire process of mathematical theory exploration within one coherent logic and software system. This survey paper illustrates the style of Theorema-supported mathematical theory exploration by a case study (the automated synthesis of an algorithm for the construction of Gröbner Bases) and gives an overview on some reasoners and organizational tools for theory exploration developed in the Theorema project.     

Two-, three-, and four-factor PCL-R models in applied sex offender risk assessments

The authors compared 2-, 3-, 4-factor, and 2-factor/4-facet Psychopathy Checklist-Revised (PCL-R) models in a previously unpublished sample of 1,566 adult male sex offenders assessed under applied clinical conditions as part of a comprehensive state-mandated community notification risk assessment procedure. "Testlets" significantly improved the performance of all models. The 3-factor model provided the best fit to the current data, followed by the 2-factor/4-facet model. The 2-factor model was not supported.     

Does analogical transfer involve a term-to-term alignment?

According to dominant models of reasoning by analogy, analogical transfer requires subjects to first define a full one-to-one correspondence between the base and the target problems. Accordingly, these models predict that if there is a cross-mapping between the base and the target (cross-mapping exists when similar or identical elements in the base and the target play different roles), the time spent transferring a property from the base to the target will be greater. The present results are inconsistent with this prediction. Indeed, if the mapping task is more difficult in the cross-mapping condition than in the control condition, the time needed to make the transfer is not affected by the presence of a cross-mapping. Consequently, we conclude that the mapping phase is not a necessary condition for transfer.     

Mechanism of Stimulus Classes Formation in Concurrent Discriminations in Rats

The Psychological Record - The two present experiments examined a premise of stimulus classes formation between discriminative stimuli in rats. Rats were concurrently trained on two discriminations...