Influence of historical landscapes, drainage evolution and ecological traits on patterns of genetic diversity in Southeast Asian freshwater snakehead fishes

Snakehead fishes in the family Channidae are obligate freshwater fishes represented by two extant genera, the African Parachannna and the Asian Channa. These species prefer still or slow flowing water bodies, where they are top predators that exercise high levels of parental care, have the ability to breathe air, can tolerate poor water quality, and interestingly, can aestivate or traverse terrestrial habitat in response to seasonal changes in freshwater habitat availability. These attributes suggest that snakehead fishes may possess high dispersal potential, irrespective of the terrestrial barriers that would otherwise constrain the distribution of most freshwater fishes. A number of biogeographical hypotheses have been developed to account for the modern distributions of snakehead fishes across two continents, including ancient vicariance during Gondwanan break-up, or recent colonisation tracking the formation of suitable climatic conditions. Taxonomic uncertainty also surrounds some members of the Channa genus, as geographical distributions for some taxa across southern and Southeast (SE) Asia are very large, and in one case is highly disjunct. The current study adopted a molecular genetics approach to gain an understanding of the evolution of this group of fishes, and in particular how the phylogeography of two Asian species may have been influenced by contemporary versus historical levels of dispersal and vicariance. First, a molecular phylogeny was constructed based on multiple DNA loci and calibrated with fossil evidence to provide a dated chronology of divergence events among extant species, and also within species with widespread geographical distributions. The data provide strong evidence that trans-continental distribution of the Channidae arose as a result of dispersal out of Asia and into Africa in the mid–Eocene. Among Asian Channa, deep divergence among lineages indicates that the Oligocene-Miocene boundary was a time of significant species radiation, potentially associated with historical changes in climate and drainage geomorphology. Mid-Miocene divergence among lineages suggests that a taxonomic revision is warranted for two taxa. Deep intra-specific divergence (~8Mya) was also detected between C. striata lineages that occur sympatrically in the Mekong River Basin. The study then examined the phylogeography and population structure of two major taxa, Channa striata (the chevron snakehead) and the C. micropeltes (the giant snakehead), across SE Asia. Species specific microsatellite loci were developed and used in addition to a mitochondrial DNA marker (Cyt b) to screen neutral genetic variation within and among wild populations. C. striata individuals were sampled across SE Asia (n=988), with the major focus being the Mekong Basin, which is the largest drainage basin in the region. The distributions of two divergent lineages were identified and admixture analysis showed that where they co-occur they are interbreeding, indicating that after long periods of evolution in isolation, divergence has not resulted in reproductive isolation. One lineage is predominantly confined to upland areas of northern Lao PDR to the north of the Khorat Plateau, while the other, which is more closely related to individuals from southern India, has a widespread distribution across mainland SE Asian and Sumatra. The phylogeographical pattern recovered is associated with past river networks, and high diversity and divergence among all populations sampled reveal that contemporary dispersal is very low for this taxon, even where populations occur in contiguous freshwater habitats. C. micropeltes (n=280) were also sampled from across the Mekong River Basin, focusing on the lower basin where it constitutes an important wild fishery resource. In comparison with C. striata, allelic diversity and genetic divergence among populations were extremely low, suggesting very recent colonisation of the greater Mekong region. Populations were significantly structured into at least three discrete populations in the lower Mekong. Results of this study have implications for establishing effective conservation plans for managing both species, that represent economically important wild fishery resources for the region. For C. micropeltes, it is likely that a single fisheries stock in the Tonle Sap Great Lake is being exploited by multiple fisheries operations, and future management initiatives for this species in this region will need to account for this. For C. striata, conservation of natural levels of genetic variation will require management initiatives designed to promote population persistence at very localised spatial scales, as the high level of population structuring uncovered for this species indicates that significant unique diversity is present at this fine spatial scale.

Fear, trust and Aborigines : The historical experience of state institutions and current encounters in the health system

Troubled dynamics between residents of an Aboriginal town in Queensland and the local health system were established during colonisation and consolidated during those periods of Australian history where the policies of 'protection' (segregation), integration and then assimilation held sway. The status of Aboriginal health is, in part, related to interactions between the residents' current and historical experiences of the health and criminal justice systems as together these agencies used medical and moral policing to legitimate dispossession, marginalisation, institutionalisation and control of the residents. The punitive regulations and ethnocentric strategies used by these institutions are within the living memory of many of the residents or in the published accounts of preceding generations. This paper explores current residents' memories and experiences.

Phylogenetic placement of the sugarcane orange rust pathogen Puccinia kuehnii in a historical and regional context

Sugarcane orange rust, caused by Puccinia kuehnii, was once considered a minor disease in the Australian sugar industry. However, in 2000 a new race of the pathogen devastated the high-performing sugarcane cultivar Q124, and caused the industry Aus$150–210 million in yield losses. At the time of the epidemic, very little was known about the genetic and pathogenic diversity of the fungus in Australia and neighbouring sugar industries. DNA sequence data from three rDNA regions were used to determine the genetic relationships between isolates within two P. kuehnii collections. The first collection comprised only recent Australian field isolates and limited sequence variation was detected within this population. In the second study, Australian isolates were compared with isolates from Papua New Guinea, Indonesia, China and historical herbarium collections. Greater sequence variation was detected in this collection and phylogenetic analyses grouped the isolates into three clades. All isolates from commercial cane fields clustered together including the recent Australianfield isolates and the Australian historical isolate from 1898.The other two clades included rust isolates from wild and garden canes in Indonesia and PNG. These rusts appeared morphologically similar to P. kuehnii and could potentially pose a quarantine threat to the Australian sugar industry. The results have revealed greater diversity in sugarcane rusts than previously thought.

Historical and Personal Perspectives on the Fall of the Berlin Wall, 1989: address to 20th anniversary forums.

The story of the fall of the Berlin Wall was an aspect of the “imagination gap” that we had to wrestle with as journalists covering the collapse of the Eastern Bloc in Europe. It was scarcely possible to believe what you found yourself reporting, and that work became a two-track process. On one hand a mass social movement was dictating the pace and direction of events; on the other, the institutional business of politics as usual, to provide a framework for all the change that was happening, had to be managed – and reported on. In later analyseds we could see, that crisis in the Soviet Union led to the crisis over the Berlin Wall; and from the fall of the Wall, came Germany’s reunification, and with that also, formation of the European Union as it is today. The government of the Federal Republic of Germany convinced its neighbours that a reunited Germany, within an expanded EU, would be a very acceptable “European Germany” -- not the leader of a “German Europe”. It committed itself financially, supporting the new Euro currency. The former communist states of Eastern Europe demanded to join and expand the EU; in order to remove themselves from the Soviet Union, enjoy human rights, and share in Western prosperity. So today, following on from the events of 1989, the European Union is an amalgam of 27 member countries, with close to 500 million citizens and accounting for 30 % of world Gross National Product.

Historical timelines : analyzing multimodal text design

The recent focus on literacy in Social Studies has been on linguistic design, particularly that related to the grammar of written and spoken text. When students are expected to produce complex hybridized genres such as timelines, a focus on the teaching and learning of linguistic design is necessary but not sufficient to complete the task. Theorizations of new literacies identify five interrelated meaning making designs for text deconstruction and reproduction: linguistic, spatial, visual, gestural, and audio design. Honing in on the complexity of timelines, this paper casts a lens on the linguistic, visual, spatial, and gestural designs of three pairs of primary school aged Social Studies learners. Drawing on a functional metalanguage, we analyze the linguistic, visual, spatial, and gestural designs of their work. We also offer suggestions of their effect, and from there consider the importance of explicit instruction in text design choices for this Social Studies task. We conclude the analysis by suggesting the foci of explicit instruction for future lessons.

How current pedagogy methods in games teaching in the UK, Australia and the US have been shaped by historical, socio cultural, environmental and political constraints

Crucial to enhancing the status and quality of games teaching in schools is a developed understanding of the teaching strategies adopted by practitioners. In this paper, we will demonstrate that contemporary games‟ teaching is a product of individual, task and environmental constraints (Newell, 1986). More specifically, we will show that current pedagogy in the U.K., Australia and the United States is strongly influenced by historical, socio-cultural environmental and political constraints. In summary, we will aim to answer the question „why do teachers teach games the way they do.‟ In answering this question, we conclude that teacher educators, who are trying to influence pedagogical practice, must understand these potential constraints and provide appropriate pre-service experiences to give future physical education teachers the knowledge, confidence and ability to adopt a range of teaching styles when they become fully fledged teachers. Essential to this process is the need to enable future practitioners to base their pedagogical practice on a sound understanding of contemporary learning theories of skill acquisition.

Deeply divergent mitochondrial lineages reveal patterns of local endemism in chironomids of the Australian Wet Tropics

The Wet Tropics bioregion of north-eastern Australia has been subject to extensive fluctuations in climate throughout the late Pliocene and Pleistocene. Cycles of rainforest contraction and expansion of dry sclerophyll forest associated with such climatic fluctuations are postulated to have played a major role in driving geographical endemism in terrestrial rainforest taxa. Consequences for the distributions of aquatic organisms, however, are poorly understood.The Australian non-biting midge species Echinocladius martini Cranston (Diptera: Chironomidae), although restricted to cool, well-forested freshwater streams, has been considered to be able to disperse among populations located in isolated rainforest pockets during periods of sclerophyllous forest expansion, potentially limiting the effect of climatic fluctuations on patterns of endemism. In this study, mitochondrial COI and 16S data were analysed for E. martini collected from eight sites spanning theWet Tropics bioregion to assess the scale and extent of phylogeographic structure. Analyses of genetic structure showed several highly divergent cryptic lineages with restricted geographical distributions. Within one of the identified lineages, strong genetic structure implied that dispersal among proximate (<1 km apart) streams was extremely restricted. The results suggest that vicariant processes, most likely due to the systemic drying of the Australian continent during the Plio-Pleistocene, might have fragmented historical E. martini populations and, hence, promoted divergence in allopatry.

An historical analysis of the development of thinking in the principal writings of Malcolm Knowles

Malcolm Shepherd Knowles was a key writer and theorist in the field of adult education in the United States. He died in 1997 and left a large legacy of books and journal articles. This thesis traced the development of his thinking over the 46-year period from 1950 to 1995. It examined the 25 works authored, co-authored, edited, reissued and revised by him during that period. The writings were scrutinised using a literature research methodology to expose the theoretical content, and a history of thought lens to identify and account for the development of major ideas. The methodology enabled a gradual unfolding of the history. A broadly-consistent and sequential pattern of thought focusing on the notion of andragogy emerged. The study revealed that after the initial phases of exploratory thinking, Knowles developed a practical-theoretical framework he believed could function as a comprehensive theory of adult learning. As his thinking progressed, his theory developed into a unified framework for human resource development and, later, into a model for the development of self-directed lifelong learners. The study traced the development of Knowles’ thinking through the phases of thought, identified the writings that belonged within each phase and produced a series of diagrammatic representations showing the evolution of his conceptual framework. The production of a history of the development of Knowles’ thought is the major outcome of the study. In addition to plotting the narrative sequence of thought-events, the history helps to explicate the factors and conditions that influenced Knowles’ thinking and to show the interrelationships between ideas. The study should help practitioners in their use and appreciation of Knowles’ works.

Cherbourg State School in historical context.

Cherbourg State School is some 300 kilometres northwest of Brisbane. It is situated in an Aboriginal community at Cherbourg with approximately 250 students, all of whom are Indigenous Australian children. Cherbourg State School aims to generate good academic outcomes for its students from kindergarten to Year 7 and nurture a strong and positive sense of what it means to be Aboriginal in today's society. In a context where the community continues to grapple with many social issues born of the historical processes of dispossession and disempowerment, Cherbourg State School is determined that its children can and will learn to become 'Strong and Smart'. It is a journey that has been charted by Chris Sarra, the school's first Aboriginal principal, in his paper Young and Black and Deadly: Strategies for Improving Outcomes for Indigenous Students, which describes how pride and expectations were engendered in the school over a four-year period from 1998. In this article the author discusses the historical context of the school and its impact on the Indigenous people of Cherbourg. The aim is to consider the historical, political, social and cultural context around the creation of Cherbourg State School. The author critically examines the historical records of the role of the State Government and the white settlers in the setting up and creation of the Aboriginal Reserve and later the primary school. Throughout the author addresses an absence � a voice missing from history � the voice of the Aboriginal people. This exercise in collective memory was designed to provide an opportunity for those who have seldom been given the opportunity to tell their story. Instead of the official view of Cherbourg School it provides a narrative which restores the victims of history to a place of dignity and indeed humanity.

The historical understandings : an overview

This chapter will explore some of the pioneering ideas about adolescence. It begins with origin of the word 'adolescence,' before probing into various perspectives related to the emergence of modern day adolescent. It then offers a look at the theoretical models of adolescence. Finally, it looks at the evolution of an adolescent in the school...

Adiabatic compression testing - part I : historical development and evaluation of fluid dynamic processes including shock-wave considerations

Adiabatic compression testing of components in gaseous oxygen is a test method that is utilized worldwide and is commonly required to qualify a component for ignition tolerance under its intended service. This testing is required by many industry standards organizations and government agencies. This paper traces the background of adiabatic compression testing in the oxygen community and discusses the thermodynamic and fluid dynamic processes that occur during rapid pressure surges. This paper is the first of several papers by the authors on the subject of adiabatic compression testing and is presented as a non-comprehensive background and introduction.

Disclosure in insurance law : contemporary and historical economic considerations

This article examines the importance of accurate classification and identification of risk with particular reference to the problem of adverse selection. It is argued that, historically, this concern was the paramount consideration influencing standard form contract formation and disclosure laws. The scope of its relevance today however is less apparent in that contemporary insurance contracting is conducted in a vastly different environment from that which prevailed at the time Lloyd's was better known as a coffee house. Accordingly, the second part of this article looks at the contemporary framework of information disclosure and those dynamics within it designed to elicit information weighing on risk forecasting : specifically, (a) direct inquiry and testing requirements; (b) signaling - or incentive based structuring of insurance contractual and (c) bargaining in the shadow of the utmost good faith doctrine. Finally, certain conclusions arising out of contemporary and historical economic considerations underpinning disclosure in insurance law are outlined.