Time dependency of molecular rate estimates and systematic overestimation of recent divergence times

Studies of molecular evolutionary rates have yielded a wide range of rate estimates for various genes and taxa. Recent studies based on population-level and pedigree data have produced remarkably high estimates of mutation rate, which strongly contrast with substitution rates inferred in phylogenetic (species-level) studies. Using Bayesian analysis with a relaxed-clock model, we estimated rates for three groups of mitochondrial data: avian protein-coding genes, primate protein-coding genes, and primate d-loop sequences. In all three cases, we found a measurable transition between the high, short-term (<1–2 Myr) mutation rate and the low, long-term substitution rate. The relationship between the age of the calibration and the rate of change can be described by a vertically translated exponential decay curve, which may be used for correcting molecular date estimates. The phylogenetic substitution rates in mitochondria are approximately 0.5% per million years for avian protein-coding sequences and 1.5% per million years for primate protein-coding and d-loop sequences. Further analyses showed that purifying selection offers the most convincing explanation for the observed relationship between the estimated rate and the depth of the calibration. We rule out the possibility that it is a spurious result arising from sequence errors, and find it unlikely that the apparent decline in rates over time is caused by mutational saturation. Using a rate curve estimated from the d-loop data, several dates for last common ancestors were calculated: modern humans and Neandertals (354 ka; 222–705 ka), Neandertals (108 ka; 70–156 ka), and modern humans (76 ka; 47–110 ka). If the rate curve for a particular taxonomic group can be accurately estimated, it can be a useful tool for correcting divergence date estimates by taking the rate decay into account. Our results show that it is invalid to extrapolate molecular rates of change across different evolutionary timescales, which has important consequences for studies of populations, domestication, conservation genetics, and human evolution.

Concept combination and the origins of complex cognition

At the core of our uniquely human cognitive abilities is the capacity to see things from different perspectives, or to place them in a new context. We propose that this was made possible by two cognitive transitions. First, the large brain of Homo erectus facilitated the onset of recursive recall: the ability to string thoughts together into a stream of potentially abstract or imaginative thought. This hypothesis is sup-ported by a set of computational models where an artificial society of agents evolved to generate more diverse and valuable cultural outputs under conditions of recursive recall. We propose that the capacity to see things in context arose much later, following the appearance of anatomically modern humans. This second transition was brought on by the onset of contextual focus: the capacity to shift between a minimally contextual analytic mode of thought, and a highly contextual associative mode of thought, conducive to combining concepts in new ways and ‘breaking out of a rut’. When contextual focus is implemented in an art-generating computer program, the resulting artworks are seen as more creative and appealing. We summarize how both transitions can be modeled using a theory of concepts which high-lights the manner in which different contexts can lead to modern humans attributing very different meanings to the interpretation of one concept.

Chlamydia pneumoniae : modern insights into an ancient pathogen

Chlamydia pneumoniae is an enigmatic human and animal pathogen. Originally discovered in association with acute human respiratory disease, it is now associated with a remarkably wide range of chronic diseases as well as having a cosmopolitan distribution within the animal kingdom. Molecular typing studies suggest that animal strains are ancestral to human strains and that C. pneumoniae crossed from animals to humans as the result of at least one relatively recent zoonotic event. Whole genome analyses appear to support this concept – the human strains are highly conserved whereas the single animal strain that has been fully sequenced has a larger genome with several notable differences. When compared to the other, better known chlamydial species that is implicated in human infection, Chlamydia trachomatis, C. pneumoniae demonstrates pertinent differences in its cell biology, development, and genome structure. Here, we examine the characteristic facets of C. pneumoniae biology, offering insights into the diversity and evolution of this silent and ancient pathogen.

Impediments to Cosmopolitan Engagement: Technology and Late-Modern Cosmopolitanism

What characterises late modern variety of cosmopolitanism from its classical predecessors is the inherent connection between cosmopolitanism and technology. Technology enables a vital dimension of the cosmopolitan experience – to move beyond the cosmopolitan imagination to enable active, direct engagement with other cultures. Different types of technologies contribute to cosmopolitan practice but in this paper we focus on a specific set of these enabling technologies: technologies which play a crucial role in regulating the free movement of people and populations. We briefly examine how three of the great surveillance states of the 20th century – Nazi Germany, the Soviet Union, and the German Democratic Republic – used hightech solutions in pursuing an anti-cosmopolitanism. We suggest that in the period from 2001 to the present, important elements of the cosmopolitan ethos are being closed down, and once again high-tech is intimately connected to this moment. The increasing (and proposed) use of identity cards, biometric identification systems, ITS and GIS all work to make the globalised world much harder to traverse and inhibit the full expression and experience of cosmopolitanism. The result of these trends may be that the type of cosmopolitan sentiment exhibited in western countries is an ersatz, emptied out variety with little political-ethical robustness.

On medium specificity and discipline crossovers in modern art : An interview with Jacques Ranciére on Medium-Specificity and Discipline Crossovers in Modern Art

Jacques Ranciere's work on aesthetics has received a great deal of attention recently. Given his work has enormous range – taking in art and literature, political theory, historiography, pedagogy and worker's history – Andrew McNamara and Toni Ross (UNSW) seek to explore his wider project in this interview, while showing how it leads to his alternative insights into aesthetics. Rancière sets aside the core suppositions linking the medium to aesthetic judgment, which has informed many definitions of modernism. Rancière is emphatic in freeing aesthetic judgment from issues of medium-specificity. He argues that the idea of autonomy associated with medium-specificity – or 'truth to the medium' – was 'a very late one' in modernism, and that post-medium trends were already evident in early modernism. While not stressing a simple continuity between early modernism and contemporary art, Ranciere nonetheless emphasizes the ethical and political ramifications of maintaining an a-disciplinary stance.

Modern landscape

Landscape is a perennial source of conceptual material for most creative disciplines, and, arguably, everything else, but it is always irritating to landscape architects how it is seized on by architects when their own canon is boring them or their language of form is getting a bit straight. What is frustrating is that while landscape architecture attempts to come to terms with factors, systems and nuances of situations that may result in form, there is a tendency in architecture to make icons of generic 'natural' archetypes. This is not to say that landscape architecture has yet developed a strong formal language that engages with these nuances, just that the struggle with them is at its root, and this struggle with specificity in the face of generic-ness is a noble one. In the face of this, to see architecture describe a 'new' and 'innovative' interest in landscape in 'the ground' seems like a diversion: surely there must be innovation in a real, articulate and sophisticated understanding of the architectural canon.

Evolutionary optimisation methods with uncertainty for modern multidisciplinary design in aeronautical engineering

One of the new challenges in aeronautics is combining and accounting for multiple disciplines while considering uncertainties or variability in the design parameters or operating conditions. This paper describes a methodology for robust multidisciplinary design optimisation when there is uncertainty in the operating conditions. The methodology, which is based on canonical evolution algorithms, is enhanced by its coupling with an uncertainty analysis technique. The paper illustrates the use of this methodology on two practical test cases related to Unmanned Aerial Systems (UAS). These are the ideal candidates due to the multi-physics involved and the variability of missions to be performed. Results obtained from the optimisation show that the method is effective to find useful Pareto non-dominated solutions and demonstrate the use of robust design techniques.

Modern Times : The Untold Story of Modernism in Australia

Richly illustrated and beautifully designed, Modern Times - The Untold Story of Modernism in Australia reveals how modernism transformed all aspects of Australian culture across five tumultuous decades from 1917 to 1967. The influence of modernism was far-reaching. "Modern Times" looks at all things modern and as diverse as art, advertising, photography, film, fashion, the body, architecture, interiors, recreational sites such as the new swimming pools and fountains, milk bars and auto culture.Modernism embodied the utopian possibilities of the twentieth century. It transformed Australian cities into complex metropolises and offered access to new cosmopolitan cultures. This is the first time that such diverse material has been brought together in one volume.

Undressing Kellerman, Uncovering Broadhurst : the modern woman and "un-Australia"

This article explores the contributions of two unique Australian women, Annette Kellerman and Florence Broadhurst, to global fashion and aesthetics through subverting and challenging female gender roles of the early twentieth century. These two women are brought together here as a means of highlighting their markedly contrasting social tactics: undressing versus layering. Kellerman's body became an instrument in her quest for global fame, engaging in daring public "undress" in swimming and diving performances around the world that served to show case her innovative swimwear design. In contrast, Broadhurst, through repeated reconstructions of her persona and constant relayering of identities, concocted versions of herself in order to pass through Shanghai, London, and Sydney societies. Their lives exist as binaristic parallels, expressing contrasting values of un-Australianness - the disavowal of national identity; and Australianness - the promotion of national identity. Both Kellerman and Broadhurst tested the limits of body, dress and national identity as vehicles for global recognition. The recent interest in their historical roles is evidenced in the films "The original Mermaid"( 2004) and "Unfolding Florence" (2005) in addition to numerous books and journal articles. Despite this resurgent public recognition of their lives and achievements, scholarly analysis of their legacies in the fields of fashion and design are still relatively neglected. This article explores their contributions to celebrity and modernity, fashion and gender as modern un-Australian women.