Children’s Reporting of Peers’ Behaviour

This thesis describes a mixed-methods investigation of young children’s everyday social communication, focusing on tattling—the reporting of a peer’s negative behaviour to an audience. There are links between tattling and the development of gossip, and thus with the evolution of cooperative norms in humans. Tattling is a daily activity for many children, but has been little studied, especially in preschool contexts. \ud Quantitative sampling and participant observation are used to characterize behavioural reporting among 3- to 4-year-olds in 2 preschools in Belfast, Northern Ireland. Quantitative sampling shows that children in these populations are biased towards reporting negative actions by peers; that they are more likely to report actions of which they themselves are the victims; that they usually tell the truth; that their reports are rarely ignored by staff; and that there are relationships between frequency of tattling and measures of social dominance and relational aggression. Participant observation shows that tattling takes place in a complex social context; that children are generally aware of its effects; and that it is driven by a range of motivations, both self-oriented and group-oriented. \ud Two story recall experiments are described, aimed at testing the hypothesis that negative bias in children’s reports arises from the greater salience of negative behaviour. The experiments do not support this hypothesis, further strengthening the idea that children are acting out of strategic considerations when they report peers’ transgressions. Behavioural reporting in preschool contexts is compared with a sample of transcripts of children’s discourse recorded in 1970s England and stored in the CHILDES database. Examples of tattling and gossip are also found in the eHRAF ethnographic database. The thesis concludes with an interactionist model of the development of tattling and gossip, in which third-party mediation helps to integrate the affective and normative components of children’s developing moral systems.\u

From hitting to tattling to gossip: An evolutionary rationale for the development of indirect aggression

Adult humans are characterized by low rates of intra-group physical aggression, relative to both human children and non-human animals. I propose that the suppression of physically aggressive tendencies has been achieved partly through the replacement of dominance hierarchies by prestige hierarchies, driven by indirect reciprocity and mediated by indirectly aggressive competition and linguistic transmission of reputations. Reviewing the developmental literature on indirect aggression and related constructs provides three pieces of evidence that evolutionarily old impulses towards physical aggression are gradually socialized into indirect aggression: (i) physical aggression falls in early childhood over the same age range during which indirect aggression increases; (ii) the same individuals engage in both physical and indirect aggression; and (iii) dominant individuals practice indirect aggression more frequently. Consideration of the developmental course of indirect aggression is complemented by analysis of similar developments in verbal behaviors that are not necessarily aggressive, namely tattling and gossip. Two developmental transitions in indirect aggression and related behaviors are postulated. The first occurs in early childhood as children become aware of norms against physical aggression. The second occurs in preadolescence with the development of increasingly covert forms of reputational competition, as children try to renegotiate their status within peer social networks

The adaptive problem of absent third-party punishment

Language is a uniquely human behaviour, which has presented unique adaptive problems. Prominent among these is the transmission of information that may affect an individual’s reputation. The possibility of punishment of those with a low reputation by absent third parties has created a selective pressure on human beings that is not shared by any other species. This has led to the evolution of unique cognitive structures that are capable of handling such a novel adaptive challenge. One of these, we argue, is the propositional theory of mind, which enables individuals to model, and potentially manipulate, their own reputation in the minds of other group members, by representing the beliefs that others have about the first party’s intentions and actions. Support for our theoretical model is provided by an observational study on tattling in two preschools, and an experimental study of giving under threat of gossip in a dictator game

Nutrient stores predict task behaviors in diverse ant species

In eusocial species, including ants and honeybees, sterile or non-reproductive workers can specialize in task-specific behaviors, such as brood care and foraging for food. The mechanisms underlying task-specific behaviors include genetic, physiological and environmental factors. Here we compare corporeal nutrient storage in nine species that differ in primary food preferences (carbohydrate-, protein- or lipid-based diet) to test whether foraging behavior is associated with lower individual nutrient stores. We also investigate whether low nutrient stores are limited to foragers or occur in other external, morphologically distinct, worker sub-castes. In six out of eight species where both brood care workers and foragers were sampled, foragers had significantly lower nutrient stores relative to brood care workers; the exceptions were two Solenopsis species. Foragers from five of these six species had lower lipid levels, supporting the link between lipid content and foraging behaviors reported in previous studies. Interestingly, three species had lower levels of both lipid and carbohydrate stores in foragers relative to brood care workers, and foragers of one species, Formica fusca, had lower carbohydrate levels but not lipid levels, suggesting that the association between nutrient stores and foraging behavior is not universal across ant species or across all seasons. In all three species with morphologically distinct sub-castes, lipid levels were lowest in non-foraging, external workers, i.e., majors or soldiers, indicating an additional link between nutrient depletion and the allocation of external tasks other than foraging

Modelling of gibbsite calcination in a fluidized bed reactor

A steady state, non‐isothermal fluidized bed reactor model for co‐current flow of gas and solids has been developed as a series of Continuous Stirred Tank Reactor (CSTR) compartments. For each CSTR compartment, mass and energy balances were coupled with a particle‐scale gibbsite calcination kinetic model previously developed by the authors. The overall solids residence time distribution is captured by the compartment calcination model. The multi‐scale model was solved numerically through an iterative procedure that alternated between solving particle‐scale and reactor‐scale parts of the model. Gas, water vapour and solids concentrations, as well as particle and gas temperatures and gibbsite conversion profiles, are predicted inside the calcination reactor. The developed model can be used to facilitate improvements in the operation and design of industrial‐scale reactors

Multi-stage shrinking core model for thermal decomposition reactions with a self-inhibiting nature

Among the variety of thermal decomposition reactions, some display self-inhibiting behaviour, where the produced gas negatively influences the reaction progress. Further, a build-up of internal pressure caused by the product gas may alter the reaction pathway over the reaction duration in a way that favours a particular pathway over others. Two well-known cases of this kind of reaction are the thermal decomposition of limestone and gibbsite, in which carbon dioxide and water vapour are the produced gases, respectively. A multi-stage, multi-reaction, shrinking core model is proposed for this type of reaction. The model emphasises the role of the produced gas, not only in the mass transfer rate, but also in the reaction kinetics. It also includes parallel and series reaction pathways, which allows for the presence of an intermediate species. The model has been applied to the conversion of gibbsite to alumina, and it includes the formation of boehmite as an intermediate product. The model results are in good agreement with experimental data for gibbsite calcination reported in the literature. Gibbsite conversion, boehmite formation and subsequent consumption, as well as alumina formation, are successfully simulated. Further, the corresponding kinetic parameters are estimated for all reactions of interest

Planar SOFC system modelling and simulation including a 3D stack module

A solid oxide fuel cell (SOFC) system consists of a fuel cell stack with its auxiliary components. Modelling an entire SOFC system can be simplified by employing standard process flowsheeting software. However, no in-built SOFC module exists within any of the commercial flowsheet simulators. In Amiri et al. (Comput. Chem. Eng., 2015, 78:10-23), a rigorous SOFC module was developed to fill this gap. That work outlined a multi-scale approach to SOFC modelling and presented analyses at compartment, channel and cell scales. The current work extends the approach to stack and system scales. Two case studies were conducted on a simulated multilayer, planar SOFC stack with its balance of plant (BoP) components. Firstly, the effect of flow maldistribution in the stack manifold on the SOFC's internal variables was examined. Secondly, the interaction between the stack and the BoP was investigated through the effect of recycling depleted fuel. The results showed that anode gas recycling could be used for managing the gradients within the stack, while also improving fuel utilisation and water management

A computational approach towards conflict resolution for serious games

Conflict is an unavoidable feature of life, but the development of conflict resolution management skills can facilitate the parties involved in resolving their conflicts in a positive manner. The goal of our research is to develop a serious game in which children may experiment with conflict resolution strategies and learn how to work towards positive conflict outcomes. While serious games related to conflict exist at present, our work represents the first attempt to teach conflict resolution skills through a game in a manner informed by sociological and psychological theories of conflict and current best practice for conflict resolution. In this paper, we present a computational approach to conflict generation and resolution. We describe the five phases involved in our conflict modeling process: conflict situation creation, conflict detection, player modeling and conflict strategy prediction, conflict management, and conflict resolution, and discuss the three major elements of our player model: assertiveness, cooperativeness, and relationship. Finally, we overview a simple resource management game we have developed in which we have begun experimenting with our conflict model concepts.peer-reviewe

A computational approach towards conflict resolution for serious games

Conflict is an unavoidable feature of life, but the development of conflict resolution management skills can facilitate the parties involved in resolving their conflicts in a positive manner. The goal of our research is to develop a serious game in which children may experiment with conflict resolution strategies and learn how to work towards positive conflict outcomes. While serious games related to conflict exist at present, our work represents the first attempt to teach conflict resolution skills through a game in a manner informed by sociological and psychological theories of conflict and current best practice for conflict resolution. In this paper, we present a computational approach to conflict generation and resolution. We describe the five phases involved in our conflict modeling process: conflict situation creation, conflict detection, player modeling and conflict strategy prediction, conflict management, and conflict resolution, and discuss the three major elements of our player model: assertiveness, cooperativeness, and relationship. Finally, we overview a simple resource management game we have developed in which we have begun experimenting with our conflict model concepts.peer-reviewe

Methodological approaches to determining the marine radiocarbon reservoir effect

The marine radiocarbon reservoir effect is an offset in 14C age between contemporaneous organisms from the terrestrial environment and organisms that derive their carbon from the marine environment. Quantification of this effect is of crucial importance for correct calibration of the <sup>14</sup>C ages of marine-influenced samples to the calendrical timescale. This is fundamental to the construction of archaeological and palaeoenvironmental chronologies when such samples are employed in <sup>14</sup>C analysis. Quantitative measurements of temporal variations in regional marine reservoir ages also have the potential to be used as a measure of process changes within Earth surface systems, due to their link with climatic and oceanic changes. The various approaches to quantification of the marine radiocarbon reservoir effect are assessed, focusing particularly on the North Atlantic Ocean. Currently, the global average marine reservoir age of surface waters, R(t), is c. 400 radiocarbon years; however, regional values deviate from this as a function of climate and oceanic circulation systems. These local deviations from R(t) are expressed as +R values. Hence, polar waters exhibit greater reservoir ages (δR = c. +400 to +800 <sup>14</sup>C y) than equatorial waters (δR = c. 0 <sup>14</sup>C y). Observed temporal variations in δR appear to reflect climatic and oceanographic changes. We assess three approaches to quantification of marine reservoir effects using known age samples (from museum collections), tephra isochrones (present onshore/offshore) and paired marine/terrestrial samples (from the same context in, for example, archaeological sites). The strengths and limitations of these approaches are evaluated using examples from the North Atlantic region. It is proposed that, with a suitable protocol, accelerator mass spectrometry (AMS) measurements on paired, short-lived, single entity marine and terrestrial samples from archaeological deposits is the most promising approach to constraining changes over at least the last 5 ky BP