No evidence for self-recognition in a small passerine,the great tit (<Emphasis Type="Italic">Parus major</Emphasis>) judged from the mark/mirror test

Self-recognition is a trait presumed to be associated with high levels of cognition and something previously considered to be exclusive to humans and possibly apes. The most common test of self-recognition is the mark/mirror test of whether an animal can understand that it sees its own reflection in a mirror. The usual design is that an animal is marked with a colour spot somewhere on the body where the spot can only be seen by the animal by using a mirror. Very few species have passed this test, and among birds, only magpies have been affirmatively demonstrated to pass it. In this study, we tested great tits (Parus major), small passerines, that are known for their innovative foraging skills and good problem-solving abilities, in the mirror self-recognition test. We found no indication that they have any ability of this kind and believe that they are unlikely to be capable of this type of self-recognition.     

Are the aesthetic preferences towards snake species already formed in pre-school aged children?

This study explores aesthetic preferences towards boa and python species among pre-school children and adults, and compares the ratings between the two groups. A set of snake photographs was presented (56 species) to children and adult respondents. The respondents were asked to select the five most preferred and five least preferred species. The children’s agreement on which species were ‘beautiful’ and which were ‘ugly’ was statistically significant and a positive relationship between the mean ranks provided by children and adults was also found (r = .54, P < .001). Children preferred species with thick necks and inconspicuous heads, usually small species, harmless to children. Large pythons probably posed more danger to children than they did to adults during human evolution in African savannas and therefore we hypothesize that young children’s aesthetic preferences were shaped by natural selection through interactions with dangerous snakes.     

Analysis of categorical moderators in mixed‐effects meta‐analysis: Consequences of using pooled versus separate estimates of the residual between‐studies variances

Subgroup analyses allow us to examine the influence of a categorical moderator on the effect size in meta‐analysis. We conducted a simulation study using a dichotomous moderator, and compared the impact of pooled versus separate estimates of the residual between‐studies variance on the statistical performance of the Q _{B (P)} and Q _{B (S)} tests for subgroup analyses assuming a mixed‐effects model. Our results suggested that similar performance can be expected as long as there are at least 20 studies and these are approximately balanced across categories. Conversely, when subgroups were unbalanced, the practical consequences of having heterogeneous residual between‐studies variances were more evident, with both tests leading to the wrong statistical conclusion more often than in the conditions with balanced subgroups. A pooled estimate should be preferred for most scenarios, unless the residual between‐studies variances are clearly different and there are enough studies in each category to obtain precise separate estimates.     

Status Incongruence and Supervisor Gender as Moderators of the Transformational Leadership to Subordinate Affective Organizational Commitment Relationship

Grounded in role congruity theory, we examine how status incongruence (when the subordinate is older, has more education, work experience, and/or organizational tenure than the supervisor) in subordinate–supervisor dyads affects transformational leaders’ ability to foster affective organizational commitment among their subordinates. Across two field studies, our findings show that the relationship between transformational leadership and subordinate affective organizational commitment is less positive when status incongruence is high. Furthermore, in both field studies we found a 3‐way interaction among transformational leadership, status incongruence, and supervisor gender predicting subordinate affective organizational commitment. Specifically, in Study 1 (pink‐collar employees in Turkey), low status incongruence strengthened the positive relationship between transformational leadership and subordinate affective organizational commitment for male leaders. In Study 2 (pink‐collar employees in the United States), low status incongruence strengthened the positive relationship between transformational leadership and subordinate affective organizational commitment for female leaders. Furthermore, Study 2 also revealed that collective identity was a mediator of both the significant 2‐ and 3‐way interaction effects on subordinate affective organizational commitment.     

The Roles of Child Gender and Parental Knowledge of Child Development in Parent-Child Interactive Play

In our study, we aimed to analyse the effect of child gender on parental and child interactive play behaviour, as well as to determine relations between parental general knowledge of child development and parental play behaviour in two developmental periods, namely toddlerhood and early childhood. The sample included 99 children (50 toddlers 1–3 years-old; 49 preschoolers 3–5 years-old) and their parents. Parent–child interactive play with a standard set of toys was observed and assessed in the home setting. We found that parental and child play behaviours were closely related in both age groups. In addition, child’s gender affected child, but not parental, play behaviour such that girls more frequently established the content of play, sustained play frame, and used more symbolic transformations during play than boys did. Parents’ general knowledge of child development was associated with both parental education and parental play behaviour. The findings are applicable to different professionals working with children and their parents in the preschool period.     

A structural equation modeling of executive functions,IQ and mathematical skills in primary students: Differential effects on number production,mental calculus and arithmetical problems

Though the relationship between executive functions (EFs) and mathematical skills has been well documented, little is known about how both EFs and IQ differentially support diverse math domains in primary students. Inconsistency of results may be due to the statistical techniques employed, specifically, if the analysis is conducted with observed variables, i.e., regression analysis, or at the latent level, i.e., structural equation modeling (SEM). The current study explores the contribution of both EFs and IQ in mathematics through an SEM approach. A total of 118 8- to 12-year-olds were administered measures of EFs, crystallized (Gc) and fluid (Gf) intelligence, and math abilities (i.e., number production, mental calculus and arithmetical problem-solving). Confirmatory factor analysis (CFA) offered support for the three-factor solution of EFs: (1) working memory (WM), (2) shifting, and (3) inhibition. Regarding the relationship among EFs, IQ and math abilities, the results of the SEM analysis showed that (i) WM and age predict number production and mental calculus, and (ii) shifting and sex predict arithmetical problem-solving. In all of the SEM models, EFs partially or totally mediated the relationship between IQ, age and math achievement. These results suggest that EFs differentially supports math abilities in primary-school children and is a more significant predictor of math achievement than IQ level.     

Because difficulty is not the same for everyone: the impact of complexity in working memory is associated with cannabinoid 1 receptor genetic variation in young adults

Individual differences in working memory ability are mainly revealed when a demanding challenge is imposed. Here, we have associated cannabinoid 1 (CB1) receptor genetic variation rs2180619 (AA, AG, GG), which is located in a potential CNR1 regulatory sequence, with performance in working memory. Two-hundred and nine Mexican-mestizo healthy young participants (89 women, 120 men, mean age: 23.26 years, SD?=?2.85) were challenged to solve a medium (2-back) vs. a high (3-back) difficulty N-back tasks. All subjects responded as expected, performance was better with the medium than the high demand task version, but no differences were found among genotypes while performing each working memory (WM) task. However, the cost of the level of complexity in N-back paradigm was double for GG subjects than for AA subjects. It is noteworthy that an additive-dosage allele relation was found for G allele in terms of cost of level of complexity. These genetic variation results support that the endocannabinoid system, evaluated by rs2180619 polymorphism, is involved in WM ability in humans.     

Emotional Distress Associated with Surgical Treatment and its Relationship with Coping Profiles Among Chronically ill Older Patients

The study determines the patterns of coping styles among older patients with hip osteoarthritis and assesses the derived profiles in terms of perceived stress and anxiety before and after arthroplasty. Sixty-one hospital patients (mean age 70.3 years) were analysed one day before arthroplasty and three months after. The participants were assessed with the Brief-COPE (coping style), PSS-10 (perceived stress) and STAI (anxiety) psychometric tests. Four coping patterns were yielded using data clustering: rational, enterprising (resourceful), potentially maladaptive and flexible. Repeated measures ANOVA indicated a main effect within subjects but did not indicate that decreases of stress and anxiety varied differently between groups. Cluster 1 (a coping profile characterised by high helplessness, low active coping, high avoidance) reported significantly greater stress and anxiety than all other groups before and after hip replacement, while clusters 2 (flexible), 3 (resourceful) and 4 (rational) were characterised by similar levels of anxiety and stress. Older patients with osteoarthritis might differ in terms of emotional response to surgical treatment. Screening for coping styles at admission to hospital may indicate more vulnerable individuals.     

Social Job Resources as Sources of Meaningfulness and its Effects on Nurses’ Vigor and Emotional Exhaustion: A Cross-Sectional Study Among Spanish Nurses

This study investigates the mediating role of psychological meaningfulness among social job resources (i.e., coworkers and supervisor support), vigor, and emotional exhaustion in a nursing context. In spite of progress in understanding which organizational influence affects nurses’ vigor and emotional exhaustion, the psychological mechanisms assumed to underlie the associations have not been fully explored. The sample for this study consisted of 171 nurses from Spanish hospitals (54.4 %) and Primary Care Centers (45.6 %). The mediation model was tested using the bootstrapping procedure. Our findings confirmed that psychological meaningfulness fully mediates the impact of social job resources on vigor at work. Moreover, psychological meaningfulness partially mediated the impact of social job resources on emotional exhaustion. Results suggest that meaningfulness plays an important role in the connection between job resources, vigor, and emotional exhaustion. The findings contribute to our understanding of the psychological processes that can explain how job resources contribute to the energetic aspect of burnout and engagement among nurses. Providing nurses with more social job resources, such as coworker and supervisor support, could activate their levels of personal meaningfulness and thus enhance their levels of well-being at work.