Inter-individual and age differences in exploration, neophobia and problem-solving ability in a Neotropical raptor (Milvago chimango)

Animal innovations have far-reaching ecological and evolutionary consequences. The occurrence and persistence of an innovation require several processes, including exploration, social and asocial learning, and low neophobia. In addition, the identity of the innovator may determine how these new behaviours are socially transmitted. Taking into account inter-individual and age differences, we investigated three correlates of animal innovation: object exploration, neophobia level and novel problem-solving ability in an opportunistic generalist raptor, the Chimango Caracara (Milvago chimango). Eighteen individuals (7 adults and 11 juveniles) were caught during the non-breeding period and housed in individual cages in outdoor aviaries. Each bird was given three tests: exploration, neophobia and problem-solving. Individuals differed in their response to novel situations both within and between age groups. Most of the juveniles were more explorative and had a lower neophobic response to a strange object than adult birds, but both age groups were able to solve a novel problem when given a food reward. In juveniles, neophobia level and problem-solving performance were inversely related; however, we found no relationship between these behaviours in adults. Exploration did not correlate with neophobia or problem-solving ability for either age group. This research is one of the few studies exploring the inter-individual and age differences in behavioural innovation and their correlates in a bird of prey. The explorative tendency, low neophobia and ability to innovate showed by M. chimango may be advantageous for this generalist and opportunistic raptor and might be some of the factors underlying its ecological success.     

Me, myself, and lie: The role of self-awareness in deception

Deception has been studied extensively but still little is known about individual differences in deception ability. We investigated the relationship between self-awareness and deception ability. We enlisted novice actors to portray varying levels of deception. Forty-two undergraduates viewed the videotaped portrayals and rated the actors’ believability. Actors with high private self-awareness were more effective deceivers, suggesting that high self-monitors are more effective at deceiving. Self-awareness may lead to knowledge of another’s mental state (i.e., Theory of Mind), which may improve an individual’s deception ability.     

Evolution of the wealth gap in child development and mediating pathways: Evidence from a longitudinal study in Bogota,Colombia

Large gaps in cognition and language on the Bayley‐III between the top and bottom household wealth quartiles in 1,330 children aged 6–42 months in a representative sample of low‐ and middle‐income families in Bogota were previously shown. Maternal education and the home environment mediated these wealth effects, whereas height‐for‐age mediated a small amount of the language deficit only. At ages 6–8 years, we relocated 72% of the children and assessed their IQ on the WISC‐V, school achievement, and behavior to investigate the evolution of the wealth gaps and potential mediators. The wealth gap in IQ at 6–8 years was significantly larger than that in a factor combining Bayley‐III language and cognition at 6–42 months; whereas the gap in achievement was larger but not significantly. Moreover, in cross‐sectional analysis, the IQ gap increased from 6 to 8 years reaching over 1 SD. In contrast, the gap in behavior was not significant in either childhood stage. Parental education and early home environment remained major mediators of the wealth gap in IQ and achievement at 6–8 years; later home environment and attending private education also had an effect; and early height‐for‐age was no longer significant. The home environment partly mediated the effect of parental education on wealth. All mediators combined explained most of the variance in the wealth gap; the remaining gaps being not significant. Results highlight the importance of the early home environment and suggest that interventions focusing on that should have long‐term benefits. Also, continued intervention through to 8 years may be desirable. A video abstract of this article can be viewed at https://youtu.be/_U53iXNww3I .     

Variables related to the emergence of differential patterns in work motivation

Several longitudinal studies have shown that motivation at work acts chaotically. In very few cases, it may be linear or random. However, the factors that might explain why these different patterns emerge have not been analysed to date. In this exploratory study, we interviewed 73 employees whose motivational patterns were previously known. The results revealed that chaotic patterns were associated with high levels of motivation, self-efficacy beliefs, and perceptions of instrumentality, and also with intrinsic personal goal orientation and a perception of high work control. Linear patterns were associated with extrinsic goals and a perception of work as difficult, and random patterns were linked to high flexibility at work.     

Body dissatisfaction in Latin and Spanish adolescents

The present paper has two aims: firstly to analyse and compare body dissatisfaction of Spanish and Latin adolescents, and secondly to determine the impact of sociocultural factors and Body Mass Index (BMI) on dissatisfaction. The sample is made up of 403 adolescents, 191 Spaniards and 212 Latin-Americans, all of them students in Basque Country high schools. They were assessed by the Body Shape Questionnaire (BSQ), the CIMEC-26 (a questionnaire designed to assess the influence of the aesthetic body model), and the BMI. The results show that the Latin adolescents have a higher level of body dissatisfaction than the Spanish. This is due to the greater influence in the Latin adolescents of sociocultural factors.     

Central ghrelin increases anxiety in the Open Field test and impairs retention memory in a passive avoidance task in neonatal chicks

Ghrelin (Grh) is an endogenous ligand for the growth hormone secretagogue receptor. Although Ghr stimulates feeding in rats, it inhibits feeding in neonatal chicks. However, little is known about other central behavioral effects of Ghr. Therefore, we investigated the Ghr effects, injected intracerebroventricularly, on anxiety and memory retention of neonatal chicks in an Open Field test and in a one-trial passive avoidance task, respectively. In the Open Field test, the administration of Ghr in a dose-dependent manner increased the latency to ambulate but decreased ambulation activity, indicating an anxiogenic effect. Furthermore, chicks trained on a passive avoidance task and injected with a dose of 30 pmol of Ghr immediately after training showed an impairment of memory retention. However, there were no significant effects on the number of pecks during the pretraining, training, retention and discrimination. In addition, different doses of Ghr produced an inhibition in food intake at different times after injection. Our results indicate that Ghr induces anxiogenesis in chicks. Moreover, we have shown for the first time that Ghr can decrease memory retention in a non-mammalian species, suggesting that Ghr may play an important role in the processes of memory retention in birds.     

On the autonomy of phonological encoding: Evidence from slips of the tongue in Spanish

The present study focuses on the relationship between the processes of lexical retrieval and phonological encoding in sentence production. An analysis of spontaneous slips of the tongue in Spanish reveals that (1) there is as yet no clear evidence for a lexical bias effect on sublexical errors (segment movement and substitution), and hence for positive feedback from phonological encoding to the level of lexical representation; and (2) meaning and form appear to be largely dissociated in lexical errors, which lends support to the hypothesis that lexical retrieval proceeds in two independent stages during sentence production. These findings are discussed in the light of two alternative accounts of language production mechanisms: the interactive activation model and the structural, processing-stages model.This research has been supported by grant no. PB87-0531 from the Dirección General de Investigación Científica y Técnica, Spanish Ministry of Education. We thank Kathryn Bock, Gary Dell, and David Swinney for helpful comments and discussion.     

Fluid intelligence, working memory and executive functioning

The causes underlying the correlation between working memory and fluid intelligence remain unknown. There are some researchers who argue that the answer can be found on the presumed executive component of working memory. However, the available empirical evidence is far from conclusive. The present study tested a sample of 229 participants. Intelligence, working memory, and executive functioning were measured by one analytic reasoning test (TRASI), a dual task combining a primary task of deductive reasoning with a secondary task of counting, and the Tower of Hanoi task, respectively. All the 3 measures were computer administered. The results indicate that the shared variance between executive functioning and working memory do not account for the relationship between intelligence and working memory. Some theoretical implications are discussed.