Abundance of introduced species at home predicts abundance away in herbaceous communities

Many ecosystems worldwide are dominated by introduced plant species, leading to loss of biodiversity and ecosystem function. A common but rarely tested assumption is that these plants are more abundant in introduced vs. native communities, because ecological or evolutionary-based shifts in populations underlie invasion success. Here, data for 26 herbaceous species at 39 sites, within eight countries, revealed that species abundances were similar at native (home) and introduced (away) sites – grass species were generally abundant home and away, while forbs were low in abundance, but more abundant at home. Sites with six or more of these species had similar community abundance hierarchies, suggesting that suites of introduced species are assembling similarly on different continents. Overall, we found that substantial changes to populations are not necessarily a pre-condition for invasion success and that increases in species abundance are unusual. Instead, abundance at home predicts abundance away, a potentially useful additional criterion for biosecurity programmes.

The paradox of invasion: Reeves’ muntjac deer invade the British Isles from a limited number of founding females

High levels of genetic diversity and high propagule pressure are favoured by conservation biologists as the basis for successful reintroductions and ensuring the persistence of populations. However, invasion ecologists recognize the ‘paradox of invasion’, as successful species introductions may often be characterized by limited numbers of individuals and associated genetic bottlenecks. In the present study, we used a combination of high-resolution nuclear and mitochondrial genetic markers to investigate the invasion history of Reeves' muntjac deer in the British Isles. This invasion has caused severe economic and ecological damage, with secondary spread currently a concern throughout Europe and potentially globally. Microsatellite analysis based on eight loci grouped all 176 introduced individuals studied from across the species' range in the UK into one genetic cluster, and seven mitochondrial D-loop haplotypes were recovered, two of which were present at very low frequency and were related to more common haplotypes. Our results indicate that the entire invasion can be traced to a single founding event involving a low number of females. These findings highlight the fact that even small releases of species may, if ignored, result in irreversible and costly invasion, regardless of initial genetic diversity or continual genetic influx.

The paradox of transparency : short-termism and the institutionalisation of Australian capital markets

As the ultimate corporate decision-makers, directors have an impact on the investment time horizons of the corporations they govern. How they make investment decisions has been profoundly influenced by the expansion of the investment chain and the increasing concentration of share ownership in institutional hands. By examining agency in light of legal theory, we highlight that the board is in fact sui generis and not an agent of shareholders. Consequently, transparency can lead to directors being 'captured' by institutional investor objectives and timeframes, potentially to the detriment of the corporation as a whole. The counter-intuitive conclusion is that transparency may, under certain conditions, undermine good corporate governance and lead to excessive short-termism.

Relative income, happiness, and utility : an explanation for the Easterlin paradox and other puzzles

The well-known Easterlin paradox points out that average happiness has remained constant over time despite sharp rises in GNP per head. At the same time, a micro literature has typically found positive correlations between individual income and individual measures of subjective well-being. This paper suggests that these two findings are consistent with the presence of relative income terms in the utility function. Income may be evaluated relative to others (social comparison) or to oneself in the past (habituation). We review the evidence on relative income from the subjective well-being literature. We also discuss the relation (or not) between happiness and utility, and discuss some nonhappiness research (behavioral, experimental, neurological) related to income comparisons. We last consider how relative income in the utility function can affect economic models of behavior in the domains of consumption, investment, economic growth, savings, taxation, labor supply, wages, and migration.

The speed paradox : the misalignment between driver attitudes and speeding behaviour

This paper reports on a study investigating preferred driving speeds and frequency of speeding of 320 Queensland drivers. Despite growing community concern about speeding and extensive research linking it to road trauma, speeding remains a pervasive, and arguably, socially acceptable behaviour. This presents an apparent paradox regarding the mismatch between beliefs and behaviours, and highlights the necessity to better understand the factors contributing to speeding. Utilising self-reported behaviour and attitudinal measures, results of this study support the notion of a speed paradox. Two thirds of participants agreed that exceeding the limit is not worth the risks nor is it okay to exceed the posted limit. Despite this, more than half (58.4%) of the participants reported a preference to exceed the 100km/hour speed limit, with one third preferring to do so by 10 to 20 km/hour. Further, mean preferred driving speeds on both urban and open roads suggest a perceived enforcement tolerance of 10%, suggesting that posted limits have limited direct influence on speed choice. Factors that significantly predicted the frequency of speeding included: exposure to role models who speed; favourable attitudes to speeding; experiences of punishment avoidance; and the perceived certainty of punishment for speeding. These findings have important policy implications, particularly relating to the use of enforcement tolerances.

Art and the sublime : the paradox of indeterminacy unknowing and (dis)orientation in the presentation of the unpresentable

the (dis)orientation of thought in its encounter with art can be understood as the direct result of an encounter with indeterminacy as a lack in meaning. As an artist I am aware of how this indeterminacy impacts on the perceived value and authority of the artistic voice and in particular its value as a research voice. This paper explores this indeterminacy of meaning, as a profound and disturbing unknowing characteristic of the sublime and argues its value to advanced thought and for any methodological understanding of practice-led research. Lyotard described the sublime as an ‘understanding’ through which art and its associated practices may be able to resist an all too easy assimilation by the public as just a consumer commodity. His thought represents an attempt to both politically and philosophically understand art’s, and particularly abstract painting’s, affect as a state of profound and positive unknowing. To talk of the sublime in art is to speak of the suspension of any comfortable certainty in being and instead to engage with the real as a limit to meaning and knowing. It is to talk of the presentation of the unpresentable as a momentary but significant dissolution of representation. This understanding of the sublime is then further explored through the cultural phenomena of the monochrome painting and applied to the work of the two contemporary artists, Franz Erhard Walter and Günter Umberg. Initially the monochrome was understood as an attempt to go beyond traditional representation and present the unpresentable. In the one hundred years or so since that initial move this understanding has broadened. The monochrome now presents itself as a genre or even project within visual art but it still has much to teach us. In the concretely abstract and performative artworks of Franz Erhard Walter and Günter Umberg, traces of this ambition remain and their work can be seen to pose questions probing our understandings and experiences of artistic meaning, its value and the real.

Re-generating the praxis of academic staff development through arts-based learning : beyond paradox

Effective staff development remains a challenge in higher education. This paper examines the non-traditional methodology of arts-based staff development, its potential to foster transformational learning and the practice of professional artistry, through perceptions of program impact. Over a three year period, eighty academics participated in one metropolitan Australian university’s arts-based academic development program. The methodology used one-on-one hermeneutic-based conversations with fifteen self-selected academics and a focus group with twenty other academics from all three years. The paper presents a learning model to engender academic professional artistry. The findings provide developers with support for using a non-traditional strategy of transformational learning.

Osteopontin expression correlates with melanoma invasion

Melanoma is one of the most aggressive cancers affecting humans. Although early melanomas are curable with surgical excision, metastatic melanomas are associated with high mortality. The mechanism of melanoma development, progression, and metastasis is largely unknown. In order to uncover genes unique to melanoma cells, we used high-density DNA microarrays to examine the gene expression profiles of metastatic melanoma nodules using benign nevi as controls. Over 190 genes were significantly overexpressed in metastatic melanomas compared with normal nevi by at least 2-fold. One of the most abundantly expressed genes in metastatic melanoma nodules is osteopontin (OPN). Immunohistochemistry staining on tissue microarrays and individual skin biopsies representing different stages of melanoma progression revealed that OPN expression is first acquired at the step of melanoma tissue invasion. In addition, blocking of OPN expression by RNA interference reduced melanoma cell numbers in vitro. Our observations suggest that OPN may be acquired early in melanoma development and progression, and may enhance tumor cell growth in invasive melanoma.

Cell invasion with proliferation mechanisms motivated by time-lapse data

Cell invasion involves a population of cells which are motile and proliferative. Traditional discrete models of proliferation involve agents depositing daughter agents on nearest- neighbor lattice sites. Motivated by time-lapse images of cell invasion, we propose and analyze two new discrete proliferation models in the context of an exclusion process with an undirected motility mechanism. These discrete models are related to a family of reaction- diffusion equations and can be used to make predictions over a range of scales appropriate for interpreting experimental data. The new proliferation mechanisms are biologically relevant and mathematically convenient as the continuum-discrete relationship is more robust for the new proliferation mechanisms relative to traditional approaches.