Parental perception of social risk and of positive potentiality of outdoor autonomy for children: The development of two instruments

An important factor that limits children's autonomy outdoors is parental perception of social danger and traffic danger. To obtain quantitative instruments for these dimensions, this work aimed to explore the validity and reliability of three scales. Two of them describe, respectively, problematic aspects of the area of residence linked to traffic and situations of social degradation that could constitute risk factors for the child's psychological and physical safety (Traffic Danger Perception Scale, Social Danger Perception Scale). The third scale investigates parental perception of the positive potentiality of outdoor autonomy for children's maturation and growth. Interviews were conducted with 377 mothers of children between 8 and 10 years of age residing in six different areas in Italy. The results indicated weak reliability of the Traffic Danger Perception Scale, which requires further investigation, and they confirmed the reliability and the construct validity of the Social Danger Perception Scale and the Perception of Positive Potentiality of Outdoor Autonomy for Children Scale. The perception of social danger was higher in mothers who live in larger urban contexts and who have more personal fear of crime and a lower sense of community. The positive perception of children's autonomy of movement was higher among mothers who live in greener areas, who have a greater sense of community and who have more neighbourhood relations.     

What can economic experiments tell us about institutional change in social–ecological systems?

Today, economic experiments are well accepted in mainstream economics. They are also widely applied in ecological economics, often focusing on institutions. Yet, many empirical studies in this field lack a sound theoretical foundation of institutions and institutional change. In this paper, I show that in a structure–agency framework three theoretical viewpoints on institutions can be distinguished. They can be viewed as (1) structures that shape incentives, (2) cognitive media, embedded in beliefs and cognition of agents, or (3) evolving from a process of agents’ choices and structural aspects. Using examples from the empirical experimental literature, I argue that all three viewpoints are mirrored in experimental practice, and that these can be organized into an institutional typology of economic experiments. Placing special emphasis on experiments with endogenous institutional choice and their relationship to evolutionary economic theory, I discuss under which conditions experiments are a useful method for the analysis of social–ecological systems, concluding that methodological and methodical innovations are an important prerequisite for challenging the dominant paradigm of neoclassical economics.     

Bankfull Regional Curves for the Alleghany Plateau/Valley and Ridge,Piedmont, and Coastal Plain Regions of Maryland

Regional curves are empirical relationships that can help identify the bankfull stage in ungaged watersheds and aid in designing the riffle dimension in stream restoration projects. Bankfull regional curves were developed from gage stations with drainage areas less than 102 mi² (264.2 km²) for the Alleghany Plateau/Valley and Ridge (AP/VR), Piedmont, and Coastal Plain regions of Maryland. The AP/VR regions were combined into one region for this project. These curves relate bankfull discharge, cross‐sectional area, width, and mean depth to drainage area within the same hydro‐physiographic region (region with similar rainfall/runoff relationship). The bankfull discharge curve for the Coastal Plain region was further subdivided into the Western Coastal Plain (WCP) and Eastern Coastal Plain (ECP) region due to differences in topography and runoff. Results show that the Maryland Piedmont yields the highest bankfull discharge rate per unit drainage area, followed by the AP/VR, WCP, and ECP. Likewise, the Coastal Plain and AP/VR streams have less bankfull cross‐sectional area per unit drainage area than the Piedmont. The average bankfull discharge return interval across the three hydro‐physiographic regions was 1.4 years. The Maryland regional curves were compared to other curves in the eastern United States. The average bankfull discharge return interval for the other studies ranged from 1.1 to 1.8 years.     

Use of total 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol as an independent biomarker to classify smoking status

Biomarkers of exposure to tobacco smoke are needed. The objective of this study was to develop total 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) as a biomarker of tobacco smoke independent of serum cotinine. Data from National Health and Nutrition Examination Survey were used to estimate cut-off points on NNAL scale to differentiate participants in various classes of smoking status. A cut-off of 13.4 pg/mL for NNAL differentiated smokers from nonsmokers with a specificity and sensitivity of 92%. NNAL can be used as an independent biomarker of exposure to tobacco smoke with high specificity and sensitivity.     

From eavesdropping on performance to copying the behavior of others: a review of public information use

Public information (PI), a form of indirect social information, is used by individuals to estimate the quality of environmental parameters. It can be acquired in two ways. One way is by noting the performance of others. The other way it can be acquired is by noting the behavioral decisions of other individuals. Performance-based PI has been observed most often in the context of food and breeding patch estimation, as well as by individuals eavesdropping on contests between others in the context of assessing the fighting ability of opponents and the quality of mates. Evidence for the acquisition of PI from behavioral decisions of others comes mostly from studies of copying behavior, although recent work suggests that it also occurs when individuals estimate the tendency of others to be altruistic. PI use appears to be widespread across many taxa, although most work has been conducted on birds and fish. Absent from the literature are clear examples of PI use in mammals. The use of PI appears to often depend on its cost of acquisition and whether it contradicts an individual’s personal prior experience. PI can be an important benefit of associating with others.     

Reproductive suppression and inbreeding avoidance in wild populations of co-operatively breeding meerkats (Suricata suricatta)

Meerkats live in co-operatively breeding familial groups in which reproduction is monopolised by a dominant pair of breeders. Offspring of the breeders are behaviourally subordinate, and typically remain in their natal group as sexually mature, non-breeding helpers. In this study, we investigated the proximate factors limiting subordinate reproduction. Evidence for reproductive suppression by dominants was investigated by comparing life history, behaviour and hormonal profiles of dominants and subordinates. Baseline levels of plasma luteinising hormone (LH) were significantly higher in dominant than in subordinate females. However, following an exogenous injection of gonadotrophin-releasing hormone (GnRH), both categories had comparable concentrations of circulating LH. There were no significant differences in pre- or post-GnRH challenge LH levels in dominant or subordinate males. Reproduction in both dominant and subordinate females rarely occurred in the absence of unrelated males. Given that groups typically comprise parents and offspring, lack of suitable mates emerged as the primary constraint on subordinate reproduction. When this constraint was removed, subordinates typically bred but at a lower rate than dominants. This difference in reproduction may be attributed to intrasexual competition manifested through direct interference by dominant females through subordinate evictions, infanticide and the abandoning of subordinate litters. We argue that differences in reproductive regulation within mammalian co-operative breeding systems may be explained by differences in the mating strategy (inbreeding versus outbreeding) and the probability that subordinates in obligate outbreeding species will encounter unrelated opposite-sex partners. Received: 19 April 2000 / Accepted: 17 July 2000     

Disease resistance: a benefit of sociality in the dampwood termite Zootermopsis angusticollis (Isoptera: Termopsidae)

The benefit of sociality in relation to disease susceptibility was studied in the dampwood termite Zootermopsis angusticollis. Although contact with high concentrations of fungal conidia is lethal, the survivorship of nymphs exposed to spore suspensions ranging from 6 × 10⁶ to 2 × 10⁸ spores/ml of the fungus Metarhizium anisopliae increased with group size. The survivorship (measured as LT₅₀) of isolated individuals ranged from 3.0 to 4.8 days, but infected nymphs living in groups of 10 and 25 individuals survived significantly longer (5.6–8.3 and 5.6–9.1 days, respectively). In most cases, there were no significant differences in the survival distributions of the 10- and 25-termite groups. When nymphs were infected with concentrations of 7 × 10¹–7 × 10⁴ spores/ml and allowed to interact with healthy nestmates, fungal infections were not contracted by the unexposed termites. Moreover, infected termites benefitted from social contact with unexposed nestmates: their survival rates were significantly higher than those of infected termites living with similarly infected nestmates. Allogrooming, which increased in frequency during and after exposure to conidia, appeared to remove potentially infectious spores from the cuticle, thus increasing termite survivorship. These results suggest that allogrooming plays a crucial role in the control of disease and its death hazard in termites. The infection-reducing advantage of group living may have been significant in the evolution of social behavior in the Isoptera. Received: 18 March 1998 / Accepted after revision: 31 May 1998     

Opportunistic discrimination of alien eggs by social wasps (Polistes biglumis, Hymenoptera Vespidae): a defense against social parasitism?

Foundresses of the social wasp Polistes biglumis were tested to see whether they were able to recognize alien eggs experimentally introduced into their own nests. Foundresses removed alien conspecific reproductive-destined eggs while they accepted worker-destined eggs. The results indicate that social wasps discriminate among eggs and that they discriminate against alien eggs destined to produce unrelated reproductives. P. biglumis is a strictly solitary founding species, with no reproductive competition within colonies; thus, brood discrimination abilities could have evolved as a counteradaptation against intra- and inter-specific brood parasitism. Received: 12 May 2000 / Revised: 15 July 2000 / Accepted 20 July 2000     

Expert risk perceptions and the social amplification of risk: A case study in invasive tree pests and diseases

The Social Amplification of Risk Framework (SARF) is often used as a conceptual tool for studying diverse risk perceptions associated with environmental hazards. While widely applied, it has been criticised for implying that it is possible to define a benchmark ‘real’ risk that is determined by experts and around which public risk perceptions can subsequently become amplified. It has been argued that this objectification of risk is particularly problematic when there are high levels of scientific uncertainty and a lack of expert consensus about the nature of a risk and its impacts. In order to explore this further, this paper examines how ‘experts’ – defined in this case as scientists, policy makers, outbreak managers and key stakeholders – construct and assemble their understanding of the risks associated with two invasive tree pest and disease outbreaks in the UK, ash dieback and oak processionary moth. Through semi-structured interviews with experts in each of the case study outbreaks, the paper aims to better understand the nature of information sources drawn on to construct perceptions of tree health risks, especially when uncertainty is prevalent. A key conclusion is that risk assessment is a socially-mediated, relational and incremental process with experts drawing on a range of official, anecdotal and experiential sources of information, as well as reference to past events in order to assemble the risk case. Aligned with this, experts make attributions about public concern, especially when the evidence base is incomplete and there is a need to justify policy and management actions and safeguard reputation.     

The effects of age and relatedness on mating patterns in thornbug treehoppers: inbreeding avoidance or inbreeding tolerance?

The social environment of many species includes synchronous maturation of siblings in family groups, followed by limited dispersal of adults from their natal site. Under these conditions, females may experience high encounter rates with same-age siblings during mate searching, increasing their risk of inbreeding. If inbreeding depression occurs, mating with a sibling is often considered maladaptive; however, in some contexts, the inclusive fitness benefits of inbreeding may outweigh the costs, favoring females that tolerate some level of inbreeding depression. We evaluated mating patterns in the treehopper Umbonia crassicornis, a semelparous species in which females encounter same-age siblings during mate searching. A female U. crassicornis that mates with a brother suffers from inbreeding depression. We used a free-choice mating design that offered females simultaneous mating opportunities with three groups of males: siblings, same-age nonsiblings, and older nonsiblings. These groups represent the types of males typically encountered by females during mate searching. Our goal was to assess whether mating patterns were influenced by inbreeding avoidance by evaluating two hypotheses: kin discrimination and age-based mating (older males cannot be siblings in this species). There was no difference in the proportions of females mating with siblings vs nonsiblings, suggesting an absence of kin discrimination. However, females mated with a greater proportion of older vs younger males. Given that females do not avoid siblings as mates despite a cost to inbreeding, our results provide a possible example of inbreeding tolerance. We also discuss some factors that may have contributed to the mating advantage of older males.