Developmental language disorder (DLD) is estimated to affect 8 per cent of primary school-aged children, and has lasting impacts on academic achievement and social-emotional and behavioural outcomes. DLD is classified as a severe and persistent impairment in the acquisition, understanding, production or use of language, occurring in the absence of comorbid neurodevelopmental disorder. The phenotype of DLD is well established, yet there is relatively limited understanding of its aetiology. A complex interaction of genetic variants and environmental factors is thought to be the cause. To date, linkage and association analyses have implicated a handful of genes in DLD populations, including CMIP and ATP2C2. While many of these variants are common in DLD, they are not consistently associated with severe language impairment, and many overlap with chromosome regions commonly associated with neurodevelopmental disorders such as intellectual disability. The effects of alternate genetic models such as copy number and rare variants may provide a gateway to understanding the complex genetic pathways of this disorder. Pleiotropy and generalisation are also important considerations in understanding the genetic architecture of DLD. Here we outline the phenotype of DLD and provide an overview of recently identified gene pathways implicated in this disorder.

Since 1788 settler law has provided a means to either prevent or progress certain forms of environmental change, according to the values and needs of the settler state. These exploitative interests of the settler state were in sharp contrast to the approach of First Nations law, of caring for country, as reflected in the ancient and continuing culture of Indigenous peoples. This chapter examines the shifting nature and focus of environmental law from the exploitative pioneering phase of the late eighteenth and nineteenth centuries, the national development and wise use of resources that followed Federation, and concludes with the rise of modern environmentalism from the 1960s. The statutes and cases examined in this chapter range from the free selection and public health acts of the colonial period, to the more recent Environment Protection and Biodiversity Act 1999 (Cth) and Telstra Corporation v Hornsby Shire Council (2006). The historical record suggests a reactionary pattern of environmental exploitation giving rise to settler environmental anxieties that stimulate legislative intervention. Despite the promise of the wave of environmental legislation of the 1970s and 1980s, Australia’s State, Territory and Federal environmental laws have proven to be relatively weak in restraining this reckless pattern of political expediency, developmentalism and short-sightedness.

At the beginning of the new millennium, Australia's cities and their peri-urban and rural hinterlands were in the midst of a worsening drought. Having developed in the mid-1990s, the Millennium Drought finally broke in 2010, at least in south-eastern Australia. It was the most severe drought experienced in southern Australia since instrumental records began in the early twentieth century, thanks to a combination of natural variability and anthropogenic climate change. The urgency of water restrictions and supply augmentation that had characterised the drought years gave way to more pressing matters of the electoral cycle. As Australian cities continue to grow, it remains be seen as to whether plans to shape the urban form as a water catchment of its own materialise beyond model suburbs and local initiatives and what their implementation might mean for the water infrastructure and cultures of the past.

After World War II, Australians and new migrants rushed to build their dream home and garden. As housing estates proliferated in the suburbs, local authorities struggled to keep pace with increasing demand for water supply and sewerage connection. In all five cities, suburbs were constructed with no roads, kerbing and channelling, or sewerage. New subdivisions had reticulated water, but manual night cart collection continued in some suburbs and septic tanks were common until sewer lines were built. As the housing stock increased and septic systems were replaced with reticulated sewerage, water supplies were stretched beyond capacity. Authorities turned to the well-worn path of dam construction to increase supply, but when consumption exceeded capacity, especially in hot, dry seasons, unpopular water restrictions were implemented, with hoses and sprinklers banned. The sight of green suburban lawns turning brown undermined the myth of unlimited supply at the turn of a tap, but expectations were reinstated as soon as it rained.

Both Indigenous and non-Indigenous Australians have learnt to cope with climate variability in meeting water needs over a range of time-scales. The five cities are locations that Aboriginal people cared for and maintained relationships with water over tens of thousands of years, knowledge of which is maintained today. In the face of a changing climate and continuing population growth, the five cities face challenges in developing and maintaining sustainable and equitable approaches to water provision and management. Each response to water management problems is shaped by path-dependent effects of earlier decisions and the ‘wicked’ nature of problems that defy simple solutions. The five cities are marked by climatic diversity, and all are at least partly built on floodplains. Each has a distinct relationship with the natural water of its hinterland and the proximity of ocean outlets for sewage disposal.

The diverse water systems and ecologies of the places that would become Australia’s capital cities sustained Aboriginal peoples for thousands of years because of two key factors: Aboriginal knowledge of water and associated wetland and riparian ecologies, and respect for life-sustaining water as a central tenet of Aboriginal cultures. For millennia, and often enduring in the wake of the violent rupture of colonisation, Aboriginal peoples understood the affordances and risks of different forms of water and preserved these understandings in robust oral traditions. This enabled them to follow seasonal abundances of water and avoid its seasonal hazards. For all Australian Indigenous cultures, water is a storied medium that connects the past and present in the ‘long now’: a living and lively substance that sustains their Country.

In the first half of the twentieth century, the replacement of labour-intensive methods of obtaining household water and disposing of wastes by networked infrastructure made possible a change in Australian housing layouts. The informal, mixed-use cottage gave way to the ‘bungalow’ with more specialised interior spaces and internal bathrooms, allowing rising living standards in working-class households. The extension of networked water supplies and sewerage, and increasing lot sizes with more space for gardens and lawns increased per capita water consumption in the five cities. To improve the sanitary condition of the ‘respectable’ working-class, State governments intervened in housing markets by providing access to low-cost suburban housing, but disparities in domestic water facilities persisted, with much of the inner city housing stock lacking internal bathrooms, laundries, toilets, hot water services, and taps. At the end of World War II, the five cities faced serious housing shortages, and with rising prosperity came strong demand for new suburban housing.

White settlers domesticated water by shaping and regulating natural water features into systems of dams, piped networks, and waste disposal facilities. Clean water is a common resource when there is no restriction on its use, and each use of the resource makes less available to others. Overuse of common water resources was an early feature of the five cities, and effective solutions were the product of democratic institutions that empowered citizens to take collective action and express demands for improved infrastructure. In Sydney, Melbourne, and Adelaide, sanitary reform through investment in networked water infrastructure in response to the threat of cholera was underway by the mid-nineteenth century; the development of effective sewerage was delayed by the costs of extension across large metropolitan areas and the fragmentation of political authority between local councils. The smaller cities, Brisbane and Perth, were slower to invest, and water supplies continued to be unreliable and subject to pollution from cesspits. By the start of the twentieth century, variations in water infrastructure systems reflected the path-dependent nature of earlier solutions, which would constrain the options available to future decision makers.

The signs of climate change continue to signal themselves through increased weather extremes. These events have major implications for the continued reliable supply of fresh water and safe removal of waste. As the limits to the environment become increasingly obvious and pressing, these constraints will serve as a significant challenge for future generations. In the past 200 years, Australians have learned a great deal about the fragility of their environment and the need to work within its limits – the wisdom of the country's first peoples still has much to teach us in our future responses to change.

In the wake of the ‘golden age’ of economic growth in the early 1970s, public provision of urban infrastructure came under the close scrutiny of governments seeking to reduce the size of their bureaucracies in the face of expanding budgets, rising prices, and increasing unemployment. Australian governments and water utilities followed the UK and USA by introducing price mechanisms to attain more efficient water use. This coincided with severe droughts that affected urban water supplies and led state governments to impose residential water restrictions, save for Brisbane, where catastrophic floods in 1974 reminded residents of their vulnerability to the elements. Growing concern for the environment, as well as the implications of environmental degradation for human health, meant that the sights, smells, and sounds of the Australian suburbs were on the eve of change. The use of suburban waterways as drains for industrial and domestic waste would no longer be tolerated, as local residents campaigned to protect built and natural environments from pollution and development projects. Such health and ecological concerns collided with the neoliberal reform agenda of the 1990s, when newly restructured water utilities faced a series of crises in their provision of water and disposal of wastes.