Tolerant and intolerant macaques show different levels of structural complexity in their vocal communication.

We tested the social complexity hypothesis which posits that animals living in complex social environments should use complex communication systems. We focused on two components of vocal complexity: diversity (number of categories of calls) and flexibility (degree of gradation between categories of calls). We compared the acoustic structure of vocal signals in groups of macaques belonging to four species with varying levels of uncertainty (i.e. complexity) in social tolerance (the higher the degree of tolerance, the higher the degree of uncertainty): two intolerant species, Japanese and rhesus macaques, and two tolerant species, Tonkean and crested macaques. We recorded the vocalizations emitted by adult females in affiliative, agonistic and neutral contexts. We analysed several acoustic variables: call duration, entropy, time and frequency energy quantiles. The results showed that tolerant macaques displayed higher levels of vocal diversity and flexibility than intolerant macaques in situations with a greater number of options and consequences, i.e. in agonistic and affiliative contexts. We found no significant differences between tolerant and intolerant macaques in the neutral context where individuals are not directly involved in social interaction. This shows that species experiencing more uncertain social interactions displayed greater vocal diversity and flexibility, which supports the social complexity hypothesis.

The function of greetings in male Tonkean macaques.

Males living in multi-male groups are both strong rivals and potential allies. In several primate species they regularly interact through ritualized exchanges known as greetings. We studied five captive groups of Tonkean macaques (Macaca tonkeana) to test five hypotheses regarding the social function of greetings. We found that greetings were mostly reciprocal interactions, and that they often involved physical contact and facial displays. Although they were mostly initiated by the higher-ranking individual in each dyad, subordinates could initiate approximately one-third of greetings, which indicates that greetings do not serve as a formal acknowledgement of dominance relationships. Although greeting frequencies were negatively correlated to the frequency of supplantations and conflicts, they were not significantly influenced by age and dominance status, showing that greetings are not used to appease partners or decrease tension between males. Males most frequently greeted partners with whom they spent more time in proximity and body contact, and this is consistent with the hypothesis that greetings play a role in reinforcing social relationships. Lastly, greetings increased in frequency between individuals involved in challenges for rank, lending support to the hypothesis that males assess the state of their social relationships through greetings.

Should I Stay or Should I Go? Seasonal Fluctuations of Wood Mouse Populations in Fields Surrounded by Woodlands.

The wood mouse Apodemus sylvaticus is common in woodlands and open areas of the Western Palearctic. Despite extensive research, little is known about its population ecology in fields in the Mediterranean area, where the climate involves great seasonal changes in environmental features. Here, we investigated wood mice seasonal fluctuations in the number of captures and population structure by sampling long-fallow fields and woodlands, i.e., oak forest and conifer plantation, in a heterogeneous landscape of central Italy. Mice were live-trapped every two months for three years (23.814 trap-days). The number of captures, mice body weight, and proportion of adult, residents and breeding individuals were analyzed. Mice dynamics changed across seasons and habitats. In fields, we recorded more captures, more reproductive individuals, and fewer non-adults and resident individuals in the warmer months compared to the colder months; mice were heavier in warmer months. During the cold season, the captures and adult proportion in fields were lower than in resource-rich woodlands. Breeding and non-resident mice were more abundant in fields than in woodlands in warmer months. Overall, the seasonal demographic variations we recorded provide evidence that fields can represent a suboptimal habitat in Mediterranean heterogeneous landscapes, acting nonetheless as a source of food resources, cover, and mates for mice in spring-summer.

Anomalous coloration in European pine marten Martes martes in Elba Island, Central Italy.

Evidence of abnormal coloration in wild animals provides useful information to better understand its adaptive function and its impact on survival. For this reason, we need to know the frequency and distribution of these abnormal phenotypes in wild populations. Here, we report two records of hypopigmentation in European pine marten Martes martes, obtained during a camera-trapping survey on Elba Island, Central Italy. We do not know what has caused anomalous coloration of pine marten on Elba Island, but it is possible that the inbreeding may have played a role in this isolated population. Although the light coloration certainly entails an increased visibility of pine martens, it is possible that the low predator pressure and the absence of other wild carnivore populations in our study could mitigate the mortality risk due to the light phenotype. The increased use of camera traps across the world can potentially facilitate the discovery of cases of anomalous colorations in wild populations, providing an unprecedented insight into the occurrence of this phenomenon in wild mammal species.

The Pre-1D Lesion of the TFCC-A New Variant of the Palmer 1D Class.

The triangular fibrocartilage complex (TFCC) is the most important stabilizer of the distal radioulnar joint (DRUJ). Its injury is the main cause for ulnar sided pain after wrist trauma. In recent years, advancements of wrist arthroscopy improved the diagnostics and treatment of the TFCC tears. The purpose of this article is to describe a variant of radial tears (1D according to Palmer), in which the radio-ulnar ligaments were ruptured in the midsubstance just before (Pre) their insertion on the sigmoid notch and illustrate the arthroscopic surgical technique used for its treatment. We name this variant of the Palmer 1D lesion, the pre-1D TFCC lesion.

Comparison between MRI and Arthroscopy of the Wrist for the Assessment of Posttraumatic Lesions of Intrinsic Ligaments and the Triangular Fibrocartilage Complex.

Background Magnetic resonance imaging (MRI) has been considered the most appropriate examination for wrist ligament injuries diagnosis, but it frequently fails to assess the intrinsic ligament lesion. Therefore, wrist arthroscopy is required to enhance and define the diagnosis. Purpose We compare the MRI imaging with wrist arthroscopy for intrinsic wrist ligaments (scapholunate [SL] and lunotriquetral [LT]) and triangular fibrocartilage complex (TFCC) injuries detection. Patients and Methods From 2007 to 2014, 532 patients affected by suspected SL, LT, and TFCC posttraumatic ligament injury have been investigated by 1.5-Tesla MRI and wrist arthroscopy. Inclusion and exclusion criteria were adopted. Only for SL ligament injury, the arthroscopic findings of complete (stage IV) and partial (stages I-III) SL ligament injury were compared with MRI findings. Statistical analysis, including sensitivity, specificity, positive and negative predictive values, positive and negative likelihood ratios, and the diagnostic odds ratio, was used to compare MRI with arthroscopic findings. Results A total of 146 patients were accepted in the study. In 68 cases of arthroscopic SL ligament lesion, MRI confirmed the diagnosis only in 50% of the cases. In partial SL lesions, MRI was positive in 24.3% and in complete SL lesions, MRI was positive in 80.6% of the cases. In 10 cases of arthroscopic LT ligament lesion, MRI was positive in 30.0% of the cases. In 33 patients with arthroscopic TFCC lesion, MRI was positive in 66.7% of the cases. Conclusion 1.5-T MRI demonstrated to fail in confirming the lesion of SL, LP, and TFCC ligaments respectively in 50, 70, and 33.3% of the cases positive at arthroscopy. In complete SL ligament lesion, MRI reaches a higher sensitivity than in partial lesion. Arthroscopy remains the best method to demonstrate the ligament lesion and obtain more information regarding the extent and quality of the ligament damage. Level of Evidence This is a Level II, retrospective comparative study.

Collective arousal when reuniting after temporary separation in Tonkean macaques.

Celebrations and bursts of communal joy can occur spontaneously in human communities based on mechanisms of emotional contagion. Some examples of similar collective excitement have been reported in animals when they reunite or anticipate rewards, but little is known about the processes and meaning of these multiple interactions. We experimentally studied such collective arousals in two captive groups of Tonkean macaques (Macaca tonkeana) within the context of reunions following the temporary separation of two subgroups. We compared the behaviors of individuals after separation periods of 2 and 48 h with a control period with no separation. This study showed that it is possible to reproducibly induce bursts of friendly interactions in which groupmates run around over a period of several minutes, embracing and grasping one another while displaying numerous affiliative vocalizations and facial expressions. The longer the period of separation, the higher and longer-lasting the rates of affiliative interactions were. Individuals affiliated more frequently with groupmates from a previously separated subgroup than with those having stayed in their own subgroup. Collective arousal was followed by a quieter period characterized by high rates of contact-sitting and social grooming. These results point at the role of collective arousals in social cohesion; they could resolve social tension and renew social relationships. We propose that the emotional state experienced by Tonkean macaques during such events represents a disposition similar to that giving rise to what we humans call "shared joy."

Arthroscopic Distal Scaphoid Resection for Scapho-Trapezium-Trapezoid Arthritis.

Background: The purpose of this study was to describe the technique of arthroscopic resection of the scaphoid head and evaluate both the clinical and radiographic results of scapho-trapezium-trapezoid osteoarthritis cases. Methods: Seventeen cases (13 men and 4 women) with a mean age of 57 years (24-74 years) were operated on from 2002 to 2015. Inclusion criteria were nontraumatic radial-sided wrist pain without improvement after 4 months of conservative treatment and positive radiographic images demonstrating the presence of osteoarthritis. All cases were evaluated preoperatively and postoperatively using visual analog scale, wrist range of motion (ROM), grip strength, and patient's work status (Mayo Wrist Score). Disabilities of the Arm, Shoulder, and Hand (DASH) and Patient-Rated Wrist/Hand Evaluation (PRWHE) questionnaires were also administered. The technique consisted of performing a 3- to 4-mm round-shaped scaphoid head resection via arthroscopy while preserving the scaphotrapezial and scaphocapitate ligament insertions. Results: At an average follow-up of 24 months, all the patients were satisfied. The results showed statistically significant improvement in pain at rest (P = .001), under maximal load (P = .0001), and in Mayo Wrist Score (MWS) (P = .0001). Wrist ROM, grip strength, DASH, and PRWHE showed an improvement without reaching statistical significance. The mean preoperative radiolunate (RL) X-ray measurement angle was 17° (-10° to 35°). The postoperative mean value was 25° (0°-45°). In the preoperative radiographic evaluation, 11 cases exceeded the "critical" 15° RL angle. At follow-up, the RL angle increased in 10 cases and remained unchanged in 7 cases. None of these cases became symptomatic. Transitory neurapraxia of the dorsal superficial branch of the radial nerve was observed in 1 case. Damage of the dorsal branch of the radial artery was immediately fixed. Conclusions: Arthroscopic resection of the distal portion of the scaphoid due to scapho-trapezium-trapezoid osteoarthritis demonstrated an effective and safe technique with less complications than open surgery.

Arthroscopic Assisted Treatment of Thumb Metacarpal Base Articular Fractures.

Fracture of the base of the thumb metacarpal (M1) is a common finding in hand trauma. Closed reduction and K-wire fixation and open reduction-internal fixation are traditional treatments of choice. The arthroscopic assisted technique has been introduced to improve intra-articular fragment reduction and to preserve fragment vascularization and capsular and ligamentous integrity along with joint stability. Indications for arthroscopic assistance are all types of intra-articular fractures or pending malunions involving the base of M1 and/or the trapezium. The aim of this article is to describe the surgical technique used in managing articular fractures of the base of M1, with arthroscopic assistance. Our experience with this technique confirms the advantages of a minimally invasive method that provides articular reduction under direct vision, with limited soft-tissue damage, and allows early rehabilitation (from day 1 after surgery). This technique is extremely valuable for high-demand patients such as manual workers or athletes. The relative disadvantage of the technique is its technical difficulty, which requires experience with small-joint arthroscopy.

Measuring complexity in organisms and organizations.

While there is no consensus about the definition of complexity, it is widely accepted that the ability to produce uncertainty is the most prominent characteristic of complex systems. We introduce new metrics that purport to quantify the complexity of living organisms and social organizations based on their levels of uncertainty. We consider three major dimensions regarding complexity: diversity based on the number of system elements and the number of categories of these elements; flexibility which bears upon variations in the elements; and combinability which refers to the patterns of connection between elements. These three dimensions are quantified using Shannon's uncertainty formula, and they can be integrated to provide a tripartite complexity index. We provide a calculation example that illustrates the use of these indices for comparing the complexity of different social systems. These indices distinguish themselves by a theoretical basis grounded on the amount of uncertainty, and the requirement that several aspects of the systems be accounted for to compare their degree of complexity. We expect that these new complexity indices will encourage research programmes aiming to compare the complexity levels of systems belonging to different realms.

Responses to a dead companion in a captive group of tufted capuchins (Sapajus apella).

The observation of specific reactions by animals to dead conspecifics raises questions about their capacity to understand death. We describe the behavior of a captive group of tufted capuchins in the hours following the death of an adult female. The behavior of 12 subjects was recorded over a 5-h period. Most group members displayed exploratory behaviors toward the corpse, peering at it, smelling, touching, lifting or pulling it at least once. Interactions with the corpse were particularly frequent in the first hour, then decreased in the following hours. The relatives of the deceased female were the most involved individuals, and her daughter spent more time near her body than the other members of the group. Rates of interaction with the body were especially high in subadult individuals. Most of the behaviors directed to the body of the deceased individual appeared to be investigative.

Prolonged transport and cannibalism of mummified infant remains by a Tonkean macaque mother.

Observations of animals' responses to dying or dead companions raise questions about their awareness of states of helplessness or death of other individuals. In this context, we report the case of a female Tonkean macaque (Macaca tonkeana) that transported the body of her dead infant for 25 days and cannibalized its mummified parts. The mother appeared agitated in the first 2 days after the birth. She then took care of her infant's corpse, which progressively dried and became mummified. In a third stage, the mother continued to transport the corpse as it started disintegrating, and she gnawed and consumed some parts of the remains. Our observations suggest that mummification of the body favored persistence of maternal behaviors by preserving the body's shape. The female gradually proceeded from strong attachment to the infant's body to decreased attachment, then finally full abandonment of the remains.

Faecal corticosterone metabolite assessment in socially housed male and female Wistar rats.

Knowledge of animals' hormonal status is important for conservation studies in wild or semi-free-ranging conditions as well as for behavioural and clinical experiments conducted in laboratory research, mostly performed on rats and mice. Faecal sampling is a useful non-invasive method to obtain steroid hormone assessments. Nevertheless, in laboratory studies, unlike other contexts, faecal sampling is less utilised. One of the issues raised is the necessity to collect samples belonging to different animals, separately. Usually, researchers using faecal sampling solve this problem through the isolation of animals or taking the cage rather than single animal as unit of study. These solutions though, could lead to unreliable measurements, and cannot be applied in many studies. Our aim was to show the biological reliability of individual faecal corticosterone metabolite (FCM) assessments in socially housed male and female Wistar rats. We analytically validated the enzyme immunoassay kit used for FCM assessments. Then, we exposed the animals to two different stress stimuli that are known to activate the hypothalamus-pituitary-adrenal axis and the following release of corticosterone to biologically validate the EIA kit: environmental enrichment and predator odour. Individual faecal sampling from social animals was collected through short-time handling. The results demonstrated that both the stimuli increased FCM levels in male and female rats showing the reliability of EIA kit assessment and the applicability of our sampling method. We also found a diurnal rhythm in FCM levels. These results could help to increase the use of faecal hormone metabolite determinations in studies conducted on rats.

Relocation stress induces short-term fecal cortisol increase in Tonkean macaques (Macaca tonkeana).

The level of glucocorticoids, especially if obtained from noninvasive sampling, can be used as an index of animal well-being, allowing evaluation of the animal's response to environmental modifications. Despite evidence that these hormones play a relevant role in energy metabolism regulation in perceived or real stress events, little is known regarding the factors that could modify the capability of animals to cope with relocation events. The aim of this research was to assess fecal cortisol metabolite concentrations before, during and after acute stress (transfer and relocation event) in two well-established social groups of Tonkean macaques (Macaca tonkeana). The results showed that the fecal levels of cortisol increased in individuals of both groups in response to the stress event, with a similar trend in males and females. Hormone levels were back to baseline values in both groups a few days after transfer and relocation. The presence of known social partners could be one of the factors that possibly facilitated the adaptation process.

Maternal exposure to environmental enrichment before and during gestation influences behaviour of rat offspring in a sex-specific manner.

The beneficial effects of Environmental Enrichment (EE) applied immediately after weaning or even in adulthood have been widely demonstrated. Less is known about the possible changes in behaviour and brain development of the progeny following the exposure of dams to EE. In order to further investigate this matter, female rats were reared in EE for 12weeks, from weaning until delivery. After having confirmed the presence of relevant behavioural effects of EE, both control and EE females underwent mating. Maternal behaviour was observed and male and female offspring were then administered a battery of behavioural test at different ages. EE mothers showed a decreased frequency of total nursing and, during the first 2days of lactation, an increase in licking/grooming behaviour. Maternal exposure to EE affected offspring behaviour in a sex-specific manner: social play behaviour and anxiety-like behaviour were increased in males but not in females and learning ability was improved only in females. As a general trend, maternal EE had a marked influence on motility in male and female offspring in both locomotor activity and swimming speed. Overall, this study highlights the importance of environmental stimulation, not only in the animals directly experiencing EE, but for their progeny too, opening the way to new hypothesis on the heritability mechanisms of behavioural traits.

Growth rates in a captive population of Tonkean macaques.

Measuring variations in body mass is necessary to gain a deeper understanding of the evolution of life-history patterns, and it provides information on the timing of sexual maturity and the development of sexual dimorphism. In this study, we collected longitudinal data on body mass from infancy to adulthood in a captive population of Tonkean macaques (Macaca tonkeana). Tests to evaluate whether social group, maternal age, and dominance rank influenced growth rates showed that they had no significant effect. We investigated the timing and magnitude of breaking points in the growth paths of males and females, and checked whether these breaking points could correspond to specific reproductive and morphological developmental events. We found that male and female Tonkean macaques have roughly equivalent body masses until around the age of four, when males go through an adolescent growth spurt and females continue to grow at a constant rate. Males not only grow faster than females, but they also continue to grow for nearly one and a half years after females have attained their full body mass. Growth rate differences account for approximately two-thirds of the body mass sexual dimorphism; only the remaining third results from continued male growth beyond the age where full body mass is reached in females. We also discovered remarkable correspondences between the timing of testicular enlargement and the adolescent growth spurt in males, and between dental development and slowdown breaking points in both sexes.

Current role of open reconstruction of the scapholunate ligament.

This paper is a review of the various surgical techniques used in repair or reconstruction of the scapholunate ligament according to the clinical stages and anatomic-pathologic findings. Arthroscopy permits a direct evaluation of the scapholunate injury and the status of the articular surfaces. Specific indications for each type of scapholunate ligament tear are proposed, from the different types of dorsal capsulodesis to bone-ligament-bone techniques and tenodesis procedures. The authors' preferred techniques and literature review of the expected outcomes are presented.