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Serotinous plants that both release seed and resprout after fire are thought to be resistant to wildfires within the range of intensities that have been experienced up until now. However, the frequency and scale of intense wildfires is increasing under climate change. We studied annual flowering and fruit‐set in a large population of Banksia spinulosa plants in south‐eastern Australia from the early 1990s to 2006. The results led us to predict that there would be little recruitment from seedlings after the next fire but good resprouting from very long‐lived lignotubers. Our study population burned in the widespread, high‐intensity wildfires of December 2019, providing an opportunity to test the hypothesis. Most above‐ground stems and cones were reduced to ash, and only 15 cones (on 10 plants) remained after the fire. We found no seedlings in the 0.3 ha site that had initially contained over 350 adult plants. Little natural mortality had been observed pre‐fire, but by 5 months after the fire, nearly 25% of lignotubers had failed to resprout. We conclude that even common and widespread resprouting species will suffer population decline and reduced genetic diversity as high‐intensity fires become more extensive and frequent. [ABSTRACT FROM AUTHOR]

Multisensory perception might provide an important marker of brain function in aging. However, the cortical structures supporting multisensory perception in aging are poorly understood. In this study, we compared regional gray matter volume in a group of middle-aged (n = 101; 49–64 years) and older (n = 116; 71–87 years) adults from The Irish Longitudinal Study on Aging using voxel-based morphometry. Participants completed a measure of multisensory integration, the sound-induced flash illusion, and were grouped as per their illusion susceptibility. A significant interaction was observed in the right angular gyrus; in the middle-aged group, larger gray matter volume corresponded to stronger illusion perception while in older adults larger gray matter corresponded to less illusion susceptibility. This interaction remained significant even when controlling for a range of demographic, sensory, cognitive, and health variables. These findings show that multisensory integration is associated with specific structural differences in the aging brain and highlight the angular gyrus as a possible "cross-modal hub" associated with age-related change in multisensory perception. • We assessed gray matter (GM) volume and sensory integration in middle and older age. • In middle-age, right Angular Gyrus (AG) GM was larger in those who integrated more. • In older age GM in the right AG was smaller in those who integrated more. • The AG may be a key structure tied to altered multisensory processing in aging. • Multisensory integration might provide a marker of neurological health in aging. [ABSTRACT FROM AUTHOR]

It is often assumed that long‐lived woody perennials with canopy‐stored seed banks steadily accumulate seeds over time since fire. Trends in flowering and fruiting have usually been inferred from synchronic studies of sites of different post‐fire ages or counting stored seeds in apparent age classes, and mostly in obligate‐seeder species. Long‐term longitudinal studies on a broader range of species are needed to fully understand the dynamics of flower and fruit production and accumulation of viable seeds. Key questions are as follows: What is the annual trend in flowering and cone production? Is this matched by accumulation of cones and seeds? How is seed germinability related to cone age at the time of a fire?We counted inflorescences and tagged cones produced annually by the resprouting shrub Banksia spinulosa in 315 plants over 13 years at one site and in 46 plants over 20 years at another. At the end of the study, we harvested all accumulated cones, burned them and assessed seed viability using germination trials.We detected enormous inter‐plant variation in reproductive effort and output. 50% of inflorescences was produced by only 10%–15% of plants. There was a potential for accumulation of massive seed banks. However, (a) only 8%–10% of inflorescences became cones; (b) only 44%–50% of these were retained until harvest; (c) many retained cones suffered seed predation; and (d) viability of retained seeds declined with cone age. The result of these processes meant that the accumulated seed bank was only two to four seeds per plant, 82%–94% of the viable seeds had been produced in 6 years prior to harvest and only 12%–26% of plants contributed to this viable seed bank.Synthesis: Cone and seed losses and declining seed viability in B. spinulosa mean that almost all viable seeds come from the past few years of flowering even though apparently intact cones may be retained for decades. If this is typical for resprouting serotinous shrubs, it is important to understand trends in flowering and fruit set over time because the magnitude of recruitment will depend on fecundity in the few years prior to a fire. [ABSTRACT FROM AUTHOR]

There is a major public health need for innovative and efficacious behavioral and cognitive interventions for smoking cessation. This randomized controlled trial evaluated the efficacy of an acceptance and commitment therapy (ACT) smartphone application in augmenting ACT group treatment for smoking cessation. One hundred fifty adults smoking 10 or more cigarettes per day were randomly assigned to 6 weekly group sessions of behavioral support, ACT, or ACT combined with the smartphone application. Access to the app was provided from the start of the in-person treatment until the 6-month follow-up assessment. Participants were encouraged to make their quit attempts after the third session, and the posttreatment assessment occurred 3 weeks later. Measures of smoking status and ACT processes were obtained at baseline, posttreatment, and 6-month follow-up. Biochemically verified quit rates in the combined, ACT, and behavioral support groups were 36% (p = .079 relative to ACT; p = .193 relative to behavioral support), 20% (p = .630 relative to behavioral support) and 24% at posttreatment, as compared with 24% (p = .630 relative to behavioral support), 24% (p = .630 relative to behavioral support) and 20% at follow-up. There was no significant difference (p = > .999) in the primary outcome of biochemically verified 7-day point-prevalence abstinence at 6-month follow-up between the combined and ACT groups. The combined group reported significantly greater smoking reduction, acceptance and present-moment awareness than the behavioral support group at posttreatment, but not at follow-up. There were no significant differences between the groups in positive mental health. Contrary to hypotheses, the ACT group did not display significant improvements in positive mental health or ACT processes relative to the behavioral support group at posttreatment or follow-up. Implications and directions for future research are discussed. [ABSTRACT FROM AUTHOR]

The article focuses on the defunct theatrical newspaper "Touchstone" in London, England in the late 19th century. A background of "Touchstone" is provided which was started by theater manager Frederick Balsir Chatterton due to his frustration of his inability to control theatre reviews, however he made it appear that editor Edgar Ray was also the proprietor. Also discussed are the factors that contributed to "Touchstone's" business failure.

The article discusses relation between Frederick Balsir Chatterton and theater critics. It states that Chatterton was the lessee of the Theatre Royal, Drury Lane, from 1866 to 1879, and mentions that Chatterton became lessee of the St James's Theatre for the 1859-60 season. It notes that Chatterton decided to take on the Lyceum again to stage Falconer's play "Woman or Love Against the World" in 1861.

Complex human cognition, such as decision-making under ambiguity, is reflected in dynamic spatio-temporal activity in the brain. Here, we combined event-related potentials with computational modelling of the time course of decision-making and outcome evaluation during the Iowa Gambling Task. Measures of choice probability generated using the Prospect Valence Learning Delta (PVL-Delta) model, in addition to objective trial outcomes (outcome magnitude and valence), were applied as regressors in a general linear model of the EEG signal. The resulting three-dimensional spatio-temporal characterization of task-related neural dynamics demonstrated that outcome valence, outcome magnitude, and PVL-Delta choice probability were expressed in distinctly separate event related potentials. Our findings showed that the P3 component was associated with an experience-based measure of outcome expectancy. [ABSTRACT FROM AUTHOR]

Background: Despite calls for integration of neurobiological methods into research on youth resilience (high competence despite high adversity), we know little about structural brain correlates of resilient functioning. The aim of the current study was to test for brain regions uniquely associated with positive functioning in the context of adversity, using detailed phenotypic classification. Methods: 1,870 European adolescents (Mage = 14.56 years, SDage = 0.44 years, 51.5% female) underwent MRI scanning and completed behavioral and psychological measures of stressful life events, academic competence, social competence, rule-abiding conduct, personality, and alcohol use. Results: The interaction of competence and adversity identified two regions centered on the right middle and superior frontal gyri; grey matter volumes in these regions were larger in adolescents experiencing adversity who showed positive adaptation. Differences in these regions among competence/adversity subgroups were maintained after controlling for several covariates and were robust to alternative operationalization decisions for key constructs. Conclusions: We demonstrate structural brain correlates of adolescent resilience, and suggest that right prefrontal structures are implicated in adaptive functioning for youth who have experienced adversity. [ABSTRACT FROM AUTHOR]

The subject matter of neuroscience research is complex, and synthesising the wealth of data from this research to better understand mental processes is challenging. A useful strategy, therefore, may be to distinguish explicitly between the causal effects of the environment on behaviour (i.e. functional analyses) and the mental processes that mediate these effects (i.e. cognitive analyses). In this article, we describe how the functional-cognitive (F-C) framework can accelerate cognitive neuroscience and also advance a functional treatment of brain activity. We first highlight that cognitive neuroscience can particularly benefit from the F-C approach by providing an alternative to the problematic practice of reducing cognitive constructs to behavioural and/or neural proxies. Next, we outline how functional (behaviour-environment) relations can serve as a bridge between cognitive and neural processes by restoring mental constructs to their original role as heuristic tools. Finally, we give some examples of how both cognitive neuroscience and traditional functional approaches can mutually benefit from the F-C framework. [ABSTRACT FROM AUTHOR]

A comprehensive account of the causes of alcohol misuse must accommodate individual differences in biology, psychology and environment, and must disentangle cause and effect. Animal models can demonstrate the effects of neurotoxic substances; however, they provide limited insight into the psycho-social and higher cognitive factors involved in the initiation of substance use and progression to misuse. One can search for pre-existing risk factors by testing for endophenotypic biomarkers in non-using relatives; however, these relatives may have personality or neural resilience factors that protect them from developing dependence. A longitudinal study has potential to identify predictors of adolescent substance misuse, particularly if it can incorporate a wide range of potential causal factors, both proximal and distal, and their influence on numerous social, psychological and biological mechanisms. Here we apply machine learning to a wide range of data from a large sample of adolescents (n = 692) to generate models of current and future adolescent alcohol misuse that incorporate brain structure and function, individual personality and cognitive differences, environmental factors (including gestational cigarette and alcohol exposure), life experiences, and candidate genes. These models were accurate and generalized to novel data, and point to life experiences, neurobiological differences and personality as important antecedents of binge drinking. By identifying the vulnerability factors underlying individual differences in alcohol misuse, these models shed light on the aetiology of alcohol misuse and suggest targets for prevention. [ABSTRACT FROM AUTHOR]

Abstract: Noninvasive investigation of human sensory processing with high temporal resolution typically involves repeatedly presenting discrete stimuli and extracting an average event-related response from scalp recorded neuroelectric or neuromagnetic signals. While this approach is and has been extremely useful, it suffers from two drawbacks: a lack of naturalness in terms of the stimulus and a lack of precision in terms of the cortical response generators. Here we show that a linear modeling approach that exploits functional specialization in sensory systems can be used to rapidly obtain spatiotemporally precise responses to complex sensory stimuli using electroencephalography (EEG). We demonstrate the method by example through the controlled modulation of the contrast and coherent motion of visual stimuli. Regressing the data against these modulation signals produces spatially focal, highly temporally resolved response measures that are suggestive of specific activation of visual areas V1 and V6, respectively, based on their onset latency, their topographic distribution and the estimated location of their sources. We discuss our approach by comparing it with fMRI/MRI informed source analysis methods and, in doing so, we provide novel information on the timing of coherent motion processing in human V6. Generalizing such an approach has the potential to facilitate the rapid, inexpensive spatiotemporal localization of higher perceptual functions in behaving humans. [Copyright &y& Elsevier]

Highlights: [•] The present study presents the first implicit measure of positive and negative future thinking. [•] Healthy and sub-clinically depressed participants completed implicit and explicit measures. [•] The findings indicate differences in the evaluation of future events between the two groups. [•] Group differences were more pronounced on the implicit measure. [ABSTRACT FROM AUTHOR]

Aló and Cançado's (this issue) primary argument is that motivation should be described in terms of an intervening variable. Furthermore, they raise secondary points concerning the status and usage of technical terms and the scope of the motivational concept in behavior analysis. We agree with Aló and Cançado that a clear definition of motivation is essential. However, we disagree with their analysis on a number of fundamental points, such as the correct use of technical terms, the range of phenomena that should be considered as motivational, and we argue that the concept of the intervening variable is incompatible with radical behaviorism. We contend that motivation is best conceptualized as factors that influence the rate of operant responding but that are not part of the operant contingency and that, as with the term reinforcement, the terms operation and process are useful distinctions that should be employed. [ABSTRACT FROM AUTHOR]

The impulsive behavior that is often characteristic of adolescence may reflect underlying neurodevelopmental processes. Moreover, impulsivity is a multi-dimensional construct, and it is plausible that distinct brain networks contribute to its different cognitive, clinical and behavioral aspects. As these networks have not yet been described, we identified distinct cortical and subcortical networks underlying successful inhibitions and inhibition failures in a large sample (n = 1,896) of 14-year-old adolescents. Different networks were associated with drug use (n = 1,593) and attention-deficit hyperactivity disorder symptoms (n = 342). Hypofunctioning of a specific orbitofrontal cortical network was associated with likelihood of initiating drug use in early adolescence. Right inferior frontal activity was related to the speed of the inhibition process (n = 826) and use of illegal substances and associated with genetic variation in a norepinephrine transporter gene (n = 819). Our results indicate that both neural endophenotypes and genetic variation give rise to the various manifestations of impulsive behavior. [ABSTRACT FROM AUTHOR]

The Ground Parrot (Pezoporus wallicus) is a rare and iconic endemic of heathlands in southern Australia. It is threatened by frequent and widespread fire. The species has been an integral element in the development of our understanding of the impacts of fire regimes in heathlands and is an integral part of conservation management of these fire-prone ecosystems. This long-term study documents the densities of Ground Parrots in three areas of long-unburnt habitat in southern New South Wales. Using area searches and aural surveys, we estimated densities of Ground Parrots at Barren Grounds Nature Reserve–Budderoo National Park (1983–2009), Beecroft Weapons Range (1997–2008) and Nadgee Nature Reserve (1995–2009). At each location, the species occurred in long-unburnt habitat (≥20 years post-fire), sometimes at high densities (≥2 birds per 10ha). We recommend that, in south-eastern Australia, fire should not be used to manipulate the ecological functioning of habitat for the persistence of Ground Parrot populations and conclude that there should be area-specific adaptive management plans that specify how the important elements of the biodiversity will be conserved and how this will be measured. [ABSTRACT FROM AUTHOR]

The concept of the motivating operation (MO) has been subject to 3 criticisms: (a) the terms and concepts employed do not always overlap with traditional behavior-analytic verbal practices; (b) the dual nature of the MO is unclear; and (c) there is a lack of adequate contact with empirical data. We offer a more parsimonious approach to motivation, extending Skinner's (1938, 1953) early work on this topic, and introduce two new key terms: consequence-valuing operation (CVO) and consequence-valuing process (CVP). Our account focuses on the value of the reinforcer in terms of the level of responding that occurs relative to some previously measured baseline. We suggest that the concepts of the CVO and CVP will facilitate the identification, analysis, and manipulation of motivational factors in the treatment of behavior disorders. [ABSTRACT FROM AUTHOR]

Adult-onset primary torsion dystonia (AOPTD) has an autosomal dominant pattern of inheritance with markedly reduced penetrance; the genetic causes of most forms of AOPTD remain unknown. Endophenotypes, markers of sub-clinical gene carriage, may be of use detecting non-manifesting gene carriers in relatives of AOPTD patients. The aim of this study was to compare the utility of the spatial discrimination threshold (SDT) and temporal discrimination threshold (TDT) as potential endophenotypes in AOPTD. Data on other published candidate endophenotypes are also considered. Both SDT and TDT testing were performed in 24 AOPTD patients and 34 of their unaffected first degree relatives; results were compared with normal values from a control population. Of the 24 AOPTD patients 5 (21%) had abnormal SDTs and 20 (83%) had abnormal TDTs. Of the 34 first degree relatives 17 (50%) had abnormal SDTs and 14 (41%) had abnormal TDTs. Discordant results on SDT and TDT testing were found in 16 (67%) AOPTD patients and 21 (62%) first degree relatives. TDT testing has superior sensitivity compared to SDT testing in AOPTD patients; although false positive TDTs are recognised, the specificity of TDT testing in unaffected relatives is not determinable. The high level of discordance between the two tests probably relates methodological difficulties with SDT testing. The SDT is an unreliable AOPTD endophenotype; TDT testing fulfils criteria for a reliable endophenotype with a high sensitivity. © 2009 Movement Disorder Society [ABSTRACT FROM AUTHOR]

Structural grey matter abnormalities have been described in adult-onset primary torsion dystonia (AOPTD). Altered spatial discrimination thresholds are found in familial and sporadic AOPTD and in some unaffected relatives who may be non-manifesting gene carriers. Our hypothesis was that a subset of unaffected relatives with abnormal spatial acuity would have associated structural abnormalities. Twenty-eight unaffected relatives of patients with familial cervical dystonia, 24 relatives of patients with sporadic cervical dystonia and 27 control subjects were recruited. Spatial discrimination thresholds (SDTs) were determined using a grating orientation task. High-resolution magnetic resonance imaging (MRI) images (1.5 T) were analysed using voxel-based morphometry. Unaffected familial relatives with abnormal SDTs had reduced caudate grey matter volume (GMV) bilaterally relative to those with normal SDTs (right Z = 3.45, left Z = 3.81), where there was a negative correlation between SDTs and GMV ( r = −0.76, r2 = 0.58, p < 0.0001). Familial relatives also had bilateral sensory cortical expansion relative to unrelated controls (right Z = 4.02, left Z = 3.79). Unaffected relatives of patients with sporadic cervical dystonia who had abnormal SDTs had reduced putaminal GMV bilaterally compared with those with normal SDTs (right Z = 3.96, left Z = 3.45). Sensory abnormalities in some unaffected relatives correlate with a striatal substrate and may be a marker of genetic susceptibility in these individuals. Further investigation of grey matter changes as a candidate endophenotype may assist future genetic studies of dystonia. [ABSTRACT FROM AUTHOR]

Background and Aims: In Australia, honey-bees have invaded systems that evolved without social insect pollinators, where many plants are adapted to vertebrate pollination. Behavioural differences between pollinators are likely to influence mating patterns, but few studies have examined this empirically in long-lived, woody, perennials. It was shown previously that outcrossing rates in Grevillea macleayana vary among populations. Here tests were conducted to determine whether the behaviour of birds and honey-bees differed between a population previously found to be highly outcrossed and two inbreeding populations. [ABSTRACT FROM PUBLISHER]

The present experiment examined temporal discounting across 3 different age bands: adolescents, adults, and older adults (mean ages 14, 46, and 73 years, respectively). A computerized task was employed in which participants were asked to choose between larger rewards available at a specified time in the future--either £100 or £1,000 (approximately $200 and $2,000, respectively)--or a smaller reward available immediately. The subjective value of the reward decreased with increasing delay for each of the 3 age groups. A hyperbola-like function adequately described the group discounting data. The adolescent group discounted significantly more than the adult group when the larger later reward (LLR) was £100 but not when the LLR was £1,000. The adolescents discounted significantly more than the older adult group when the LLR was either £100 or £1,000. There were no significant differences in discounting between the adult and older adult groups. The results of the present study suggest that the rate of temporal discounting is higher in adolescents than in adults but is stable from middle adulthood to older adulthood. Furthermore, the process of temporal discounting appears to be quantitatively similar across the life span. [ABSTRACT FROM AUTHOR]

Spatial patterns of fruit set within inflorescences may be controlled by pollination, nutrient allocation, or inflorescence architecture. Generally, flowers that have spatial and/or temporal precedence are more likely to set fruits. We sought to separate these factors by comparing patterns of fruit set on inflorescences of two species of Telopea (Proteaceae); one that flowers from the tip to the base of the rachis, the other from base to tip. In both species, most fruits were set at the top of the inflorescence (the last flowers to open for T. speciosissima) and this was extreme for T. mongaensis, where the top flowers open first. Fruit set was not generally limited by inadequate pollination for either T. mongaensis or T. speciosissima, as hand pollinations did not increase fruit set and many abscised flowers contained pollen tubes. In T. speciosissima, we tested whether removal of developing topmost fruits would ‘release’ those that had initiated but not yet aborted lower down. There was no significant effect. Plant hormones can increase the degree to which a developing fruit is a sink for nutrients, so we applied cytokinin to the developing lower fruits on some inflorescences. There was no significant effect of the hormone treatment. We conclude that temporal precedence may contribute to the skewed pattern of fruit set in T. mongaensis, because there was an extreme concentration of fruit set on the distal part of the inflorescences, but it cannot explain this pattern of fruit set in T. speciosissima, where the distal flowers are the last to open. Some other process must therefore constrain fruit set to the topmost flowers in an inflorescence. While cytokinin application had no significant effect, the power of this experiment was low and we consider that the hypothesis of hormonal control is worth further exploration. [ABSTRACT FROM AUTHOR]

Litter accumulation after fire influences the magnitude of seed predation and seed germination. How litter accumulation and patchiness influence postfire seedling recruitment is poorly known. Species with persistent seed banks have seeds available for germination in the immediate postfire period. In contrast, plants with transient seed banks must flower after fire to place seeds in the postfire habitat. In southeastern Australian sclerophyll forests, most seedling recruitment occurs within 3 yr after fire. We found that less litter had accumulated in sites <6 mo postfire than in those 2-3 yr postfire. Seedlings of species with persistent seed banks therefore encounter postfire environments with large areas covered by little or no litter. Among these species there is great variation in seed mass, including some species with very light seeds. In contrast, the seed mass of transient seed bank species is less variable, with the lightest species more than 70 times heavier than the lightest persistent seed bank species. These seeds arrive 1-3 yr postfire and encounter habitats with more litter and fewer bare patches. This pattern suggests that litter accumulation after fire has influenced the evolution of seed mass either directly, by affecting germination and seedling survival, or indirectly, by affecting seed predators. [ABSTRACT FROM AUTHOR]

Most analyses of reaction time (RT) data are conducted by using the statistical techniques with which psychologists are most familiar, such as analysis of variance on the sample mean. Unfortunately, these methods are usually inappropriate for RT data, because they have little power to detect genuine differences in RT between conditions. in addition, some statistical approaches can, under certain circumstances, result in findings that are artifacts of the analysis method itself. A corpus of research has shown more effective analytical methods, such as analyzing the whole RT distribution, although this research has had limited influence. The present article will summarize these advances in methods for analyzing RT data. [ABSTRACT FROM AUTHOR]

The Pacific eLearning Observatory at the University of the South Pacific (USP) conducted an online survey of educational technologists (n = 60) to assess levels of access to information and communication technologies (ICT) in education and identify ways of lowering the barriers to ICT in the Pacific region. Almost half of USP's 22,000 students are distance based, and access to ICT defines their learning activities. The survey addressed perceptions of educational ICT, development strategies and initiatives, and 'guesstimates' of ICT accessibility. Results show ICT access between 1 and 11%, with tertiary-level access at 70%. Capacity building, curriculum development, infrastructure, policy, and government support are the most important development factors. Findings are analysed through eight barriers to education, and proposals are made to help USP improve access to ICT in the region. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to an article about the book "Neural Theories of Mind: Why the Mind-Brain Problem May Never Be Solved" in the summer 2007 issue.

Abstract: Native plants in gardens can potentially aid conservation by contributing to genetic diversity and buffering small and otherwise isolated populations from extinction. However, gene flow from such plantings may threaten the genetic integrity of natural populations. We assessed the morphological and genetic diversity of garden plants in an urban population of Grevillea macleayana in south-eastern Australia. There were two main groups of garden plants: some similar to plants in nearby natural populations; others with unusual morphology. Multivariate analysis of morphological characters separated these groupings, which were confirmed by genetic analysis. Both groups produced seeds and flowering phenologies overlapped, indicating a potential for gene flow. Hand pollination showed that plants in each group could fertilize flowers of the other. Thus, these garden plants contributed to genetic variation in an urban/bushland metapopulation but there was potential for gene flow from the unusual plants. Unless carefully managed, garden plants may therefore cause disruption of the genetic integrity of nearby natural populations. [Copyright &y& Elsevier]

Abstract: In plants, understanding the interactions between breeding systems and pollination ecology may enable us to predict the impacts of rarity. We used a comparative approach to test whether rarity is associated with reproductive biology in two closely-related species pairs. This system has been recently altered by changes in fire regimes and the introduction of European honeybees. More than 35% of flowers matured fruits in the common species after natural-pollination compared to &#60;20% of flowers in the rare species. All species were obligate outcrossers in each of the study populations, but only the two rare species were pollen-limited, having significantly lower fruit-set on open-pollinated flowers than those cross-pollinated by hand (mean±SE; 0.18±0.02 vs. 0.42±0.05; p &#60;0.001). Native bees (Leioproctus species) and introduced honeybees (Apis mellifera) visited all species. The native bees visited fewer flowers within a plant and moved greater distances between plants while foraging than honeybees, so the native bees are expected to be more effective in promoting outcrossing. While honeybees were the most frequent visitors to flowers of all species, native bees made more visits to common than rare species (0.65±0.20 vs. 0.20±0.09). Our results suggest that the poorer reproductive success in rare Persoonia species is associated with lower pollinator effectiveness, which is exacerbated by frequent fires and introduced honeybees. If this is a causal relationship, this may increase the probability of extinction in populations of these species. [Copyright &y& Elsevier]

The current experiment investigated the effect of differential training histories on responses to a 5-term linear chain of nonsense syllables (described here with sequential, alphabetical characters; AC | E>D), All-Less (AA | C>B | D>C | E>D). The contextual cues served as sample stimuli, and 2 nonsense words as comparison stimuli. Twenty unreinforced probe trials were subsequently administered on all possible derived relations: directly trained, mutually entailed, and 1-, 2- and 3-node combinatorially entailed relation types. Comparisons of response latencies among 1-, 2-, and 3-node combinatorially entailed relations, for accurate performances on all 20 test trials, indicated that the former produced significantly longer latencies than the latter 2 relations. Comparisons of response latencies across the 3 training structures indicated that latencies were significantly lower in the All-More condition relative to both the Less-More and the All-Less conditions. The effects of nodal distance are readily predicted by both associative accounts and Relational Frame Theory, but the effect of training structure is readily predicted only by the latter theory. The reported findings are also broadly in accordance with previous studies on relational inferences reported in the literature from mainstream cognitive psychology. [ABSTRACT FROM AUTHOR]