Fighting for shells: how private information about resource value changes hermit crab pre-fight displays and escalated fight behaviour

Pre-fight displays typically provide honest, but sometimes dishonest, information about resource holding potential and may be influenced by assessment of resource value and hence motivation to acquire the resource. These assessments of potential costs and benefits are also predicted to influence escalated fight behaviour. This is examined in shell exchange contests of hermit crabs in which we establish an information asymmetry about a particularly poor quality shell. The poor shell was created by gluing sand to the interior whereas control shells lacked sand and the low value of the poor shell could not be accurately assessed by the opponent. Crabs in the poor shell showed changes in the use of pre-fight displays, apparently to increase the chances of swapping shells. When the fights escalated, crabs in poor shells fought harder if they took the role of attacker but gave up quickly if in the defender role. These tactics appear to be adaptive but do not result in a major shift in the roles taken or outcome. We thus link resource assessment with pre-fight displays, the roles taken, tactics used during escalation and the outcome of these contests.

Roles for the subiculum in spatial information processing, memory, motivation and the temporal control of behaviour

The subiculum is in a pivotal position governing the output of the hippocampal formation. Despite this, it is a rather under-explored and sometimes ignored structure. Here, we discuss recent data indicating that the subiculum participates in a wide range of neurocognitive functions and processes. Some of the functions of subiculum are relatively well-known-these include providing a relatively coarse representation of space and participating in, and supporting certain aspects of, memory (particularly in the dynamic bridging of temporal intervals). The subiculum also participates in a wide variety of other neurocognitive functions too. however. Much less well-known are roles for the subiculum, and particularly the ventral subiculum, in the response to fear, stress and anxiety, and in the generation of motivated behaviour (particularly the behaviour that underlies drug addiction and the response to reward). There is an emerging suggestion that the subiculum participates in the temporal control of behaviour. It is notable that these latter findings have emerged from a consideration of instrumental behaviour using operant techniques; it may well be the case that the use of the watermaze or similar spatial tasks to assess subicular function (on the presumption that its functions are very similar to the hippocampus proper) has obscured rather than revealed neurocognitive functions of subiculum. The anatomy of subiculum suggests it participates in a rather subtle fashion in a very broad range of functions, rather than in a relatively more isolated fashion in a narrower range of functions, as might be the case for

Prospective information for pass decisional behaviour in Rugby Union

Decision-making requires the perception of relevant information variables that emerge from the player–environment interaction. The purpose of the present article is to empirically assess whether players’ decisional behavior about which type of pass to make is influenced by the spatio-temporal variable tau. Time series positional data of rugby players were analyzed from video footage taken in real match scenarios. The tau of the distance motion gap between attacker and defender was calculated, along with the duration of the next pass. Results revealed that the initial tau value predicted 64% of the variance found in pass duration. A qualitative distinction of tau dynamics between two periods of the approach between the attacker and the defender was also observed. We argue that the time-to-contact between the attacker and the defender may yield information about future pass possibilities. Additionally, the informational fields constraining attacker–defender interaction may be viewed as a convergent channeling of possibilities towards a single pass solution.

Sexual behaviour of young people in Northern Ireland: First sexual experience

Two National Surveys of Sexual Attitudes and Lifestyles in Britain (Natsal) were conducted, one in 1990 and one in 2000. Northern Ireland was excluded from both studies. Now, for the first time, comparable data about sexual attitudes and lifestyles of young people (14- to 25-year-olds) in Northern Ireland are available. Data were collected through self-administered questionnaires, one-to-one interviews and focus-group discussions. As in Natsal 1990 and 2000, young people were asked about their sexual attitudes towards sex, experiences of sex education, knowledge of sexually transmitted infections (STIs) and, if sexually active, about the circumstances in which sexual intercourse occurred. A total of 1013 young people in the target age group completed the self-administered questionnaire. Young people in Northern Ireland do not differ significantly from their counterparts in Britain in terms of sexual lifestyles and attitudes. Some 53.3% of all respondents reported that they had had sexual intercourse. Condom use at first sex was reported by 64% of sexually active respondents; 27.4% said they used no contraception; 26.7% of all respondents said they had sex before age 16. Respondents who first had sex when they were 15 or 16 years were more likely than other respondents to say that 'being drunk' was the main reason why intercourse occurred. Peer pressure to engage in sex was more prevalent among males than females. Young people in Northern Ireland regard friends as their most important source of sex education. School is the second most important source but most respondents wanted more sex education in school. It is important that it is needs focused and includes potentially sensitive and contentious information.

Making the law accessible to non-lawyers: effects of different kinds of expertise on perceived usability of online legal information services

To help design an environment in which professionals without legal training can make effective use of public sector legal information on planning and the environment - for Add-Wijzer, a European e-government project - we evaluated their perceptions of usefulness and usability. In concurrent think-aloud usability tests, lawyers and non-lawyers carried out information retrieval tasks on a range of online legal databases. We found that non-lawyers reported twice as many difficulties as those with legal training (p = 0.001), that the number of difficulties and the choice of database affected successful completion, and that the non-lawyers had surprisingly few problems understanding legal terminology. Instead, they had more problems understanding the syntactical structure of legal documents and collections. The results support the constraint attunement hypothesis (CAH) of the effects of expertise on information retrieval, with implications for the design of systems to support the effective understanding and use of information.

Using time-to-contact information to assess potential collision modulates both visual and temporal prediction networks

Accurate estimates of the time-to-contact (TTC) of approaching objects are crucial for survival. We used an ecologically valid driving simulation to compare and contrast the neural substrates of egocentric (head-on approach) and allocentric (lateral approach) TTC tasks in a fully factorial, event-related fMRI design. Compared to colour control tasks, both egocentric and allocentric TTC tasks activated left ventral premotor cortex/frontal operculum and inferior parietal cortex, the same areas that have previously been implicated in temporal attentional orienting. Despite differences in visual and cognitive demands, both TTC and temporal orienting paradigms encourage the use of temporally predictive information to guide behaviour, suggesting these areas may form a core network for temporal prediction. We also demonstrated that the temporal derivative of the perceptual index tau (tau-dot) held predictive value for making collision judgements and varied inversely with activity in primary visual cortex (V1). Specifically, V1 activity increased with the increasing likelihood of reporting a collision, suggesting top-down attentional modulation of early visual processing areas as a function of subjective collision. Finally, egocentric viewpoints provoked a response bias for reporting collisions, rather than no-collisions, reflecting increased caution for head-on approaches. Associated increases in SMA activity suggest motor preparation mechanisms were engaged, despite the perceptual nature of the task.

Imperfect assessment and limited information preclude optimal strategies in male-male fights in the orb-weaving spider Metellina mengei

Agonistic behaviour between male orb-web spiders Metellina mengei competing for access to female webs was examined in field experiments to test the major predictions of game theory. Winners of fights were significantly larger than losers, particularly with respect to the length of the first pair of legs, which are sexually dimorphic in this species and used extensively in agonistic encounters. The size of the winning male had no influence on contest intensity or duration, and neither did relative size. However, fight intensity and duration were both positively correlated with the size of the losing male. Resident males won significantly more contests than intruders. Winning intruders were significantly larger than winning residents and it was these winning intruders that tended to produce the longer fights. Female weight and hence reproductive value had a marked influence on fight intensity and duration of fights won by the intruder but not those won by the resident. This indicates that only the resident obtains information about the female. These data are discussed with reference to the discrepancy with theory and a failure of some contestants to obtain information on resource value and relative contestant size necessary to optimize fight strategy.

Information gathering and decision making about resource value in animal contests

Contestants are predicted to adjust the cost of a fight in line with the perceived value of the resource and this provides a way of determining whether the resource has been assessed. An assessment of resource value is predicted to alter an animal's motivational state and we note different methods of measuring that state. We provide a categorical framework in which the degree of resource assessment may be evaluated and also note limitations of various approaches. We place studies in six categories: (1) cases of no assessment, (2) cases of internal state such as hunger influencing apparent value, (3) cases of the contestants differing in assessment ability, (4) cases of mutual and equal assessment of value, (5) cases where opponents differ in resource value and (6) cases of particularly complex assessment abilities that involve a comparison of the value of two resources. We examine the extent to which these studies support game theory predictions and suggest future areas of research. (C) 2008 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.

Information Disclosure, Market Discipline and the Management of Bank Capital: Evidence from the Chinese Financial Sector

Is there evidence that market forces effectively discipline risk management behaviour within Chinese financial institutions? This study analyses information from a comprehensive sample of Chinese banks over the 1998-2008 period. Market discipline is captured through the impact of four sets of factors namely, market concentration, interbank deposits, information disclosure, and ownership structure. We find some evidence of a market disciplining effect in that: (i) higher (lower) levels of market concentration lead banks to operate with a lower (higher) capital buffer; (ii) joint-equity banks that disclose more information to the public maintain larger capital ratios; (iii) full state ownership reduces the sensitivity of changes in a bank's capital buffer to its level of risk;(iv) banks that release more transparent financial information hold more capital against their non-performing loans. © 2010 Springer Science+Business Media, LLC.

User behaviour, best practice and the risks of non-target exposure associated with anticoagulant rodenticide use

Usage of anticoagulant rodenticides (ARs) is an integral component of modern agriculture and is essential for the control of commensal rodent populations. However, the extensive deployment of ARs has led to widespread exposure of a range of non-target predatory birds and mammals to some compounds, in particular the second-generation anticoagulant rodenticides (SCARS). As a result, there has been considerable effort placed into devising voluntary best practice guidelines that increase the efficacy of rodent control and reduce the risk of non-target exposure. Currently, there is limited published information on actual practice amongst users or implementation of best practice. We assessed the behaviour of a typical group of users using an on-farm questionnaire survey. Most baited for rodents every year using SGARs. Most respondents were apparently aware of the risks of non-target exposure and adhered to some of the best practice recommendations but total compliance was rare. Our questionnaire revealed that users of first generation anticoagulant rodenticides rarely protected or checked bait stations, and so took little effort to prevent primary exposure of non-targets. Users almost never searched for and removed poisoned carcasses and many baited for prolonged periods or permanently. These factors are all likely to enhance the likelihood of primary and secondary exposure of non-target species. (C) 2010 Published by Elsevier Ltd.

Behavioural and cognitive behavioural training interventions for assisting foster carers in the management of difficult behaviour.

Background The provision of training for foster carers is now seen as an important factor contributing to the successful outcome of foster care placements. Since the late 1960s, foster carer training programs have proliferated, and few of the many published and unpublished training curricula have been systematically evaluated. The advent of cognitive-behavioural therapy (CBT) and the research evidence demonstrating its effectiveness as a psychotherapeutic treatment of choice for a range of emotional and behavioural problems, has prompted the development of CBT-based training programmes. CBT approaches to foster care training derive from a ’skill-based’ training format that also seeks to identify and correct problematic thinking patterns that are associated with dysfunctional behaviour by changing and/or challenging maladaptive thoughts and beliefs. Objectives To assess the effectiveness of cognitive-behavioural training interventions in improving a) looked-after children’s behavioural/relationship problems, b) foster carers’ psychological well-being and functioning, c) foster family functioning, d) foster agency outcomes. Search methods We searched databases including: CENTRAL (Cochrane Library Issue 3, 2006), MEDLINE (January 1966 to September 2006), EMBASE (January 1980 to September 2006), CINAHL (January 1982 to September 2006), PsycINFO (January 1872 to September 2006), ASSIA (January 1987 to September 2006), LILACS (up to September 2006), ERIC (January 1965 to September 2006), Sociological Abstracts (January 1963 to September 2006), and the National Research Register 2006 (Issue 3).We contacted experts in the field concerning current research. Selection criteria Random or quasi randomised studies comparing behavioural or cognitive-behavioural-base Data collection and analysis Two authors independently assessed trial quality and extracted data. We contacted study authors for additional information. Main results Six trials involving 463 foster carers were included. Behavioural and cognitive-behavioural training interventions evaluated to date appear to have very little effect on outcomes relating to looked-after children, assessed in relation to psychological functioning, extent of behavioural problems and interpersonal functioning. Results relating to foster carer(s) outcomes also show no evidence of effectiveness in measures of behavioural management skills, attitudes and psychological functioning. Analysis pertaining to fostering agency outcomes did not show any significant results. However, caution is needed in interpreting these findings as their confidence intervals are wide. Authors’ conclusions There is currently little evidence about the efficacy of behavioural or cognitive-behavioural training intervention for foster carers. The need for further research in this area is highlighted.

Information disclosure and depositor discipline in the Chinese banking sector

We investigate the relationship between information disclosure and depositor behaviour in the Chinese banking sector. Specifically, we enquire whether enhanced information disclosure enables investors to more effectively infer a banking institution's risk profile, thereby influencing their deposit decisions. Utilising an unbalanced panel, incorporating financial data from 169 Chinese banks over the 1998–2009 period, we employ generalised-method-of-moments (GMM) estimation procedures to control for potential endogeneity, unobserved heterogeneity, and persistence in the dependent variable. We uncover evidence that: (i) the growth rate of deposits is sensitive to bank fundamentals after controlling for macroeconomic factors, diversity in ownership structure, and government intervention; (ii) a bank publicly disclosing more transparent information in its financial reports, is more likely to experience growth in its deposit base; and (iii) banks characterised by high information transparency, well-capitalised and adopted international accounting standards, are more able to attract funds by offering higher interest rates.