In June 2022, it was estimated that around 7.3 percent of Australians were aged between 25 and 29, and the same applied to people aged between 30 and 34. All in all, about 55 percent of Australia’s population was aged 35 years or older as of June 2022. At the same time, the age distribution of the country also shows that the share of children under 14 years old was still higher than that of people over 65 years old. A breakdown of Australia’s population growth Australia is the sixth-largest country in the world, yet with a population of around 26 million inhabitants, it is only sparsely populated. Since the 1970s, the population growth of Australia has remained fairly constant. While there was a slight rise in the Australian death rate in 2022, the birth rate of the country decreased after a slight rise in the previous year. The fact that the birth rate is almost double the size of its death rate gives the country one of the highest natural population growth rates of any high-income country.
National distribution of the population Australia’s population is expected to surpass 28 million people by 2028. The majority of its inhabitants live in the major cities. The most populated states are New South Wales, Victoria, and Queensland. Together, they account for over 75 percent of the population in Australia.

Since the 1960s, Australia's urbanization rate has consistently been above 80 percent, and in 2024 it has reached its highest ever rate at 86.75 percent. Historically, Australia has been one of the most urbanized countries in the world, due to high rates of immigration since the 20th century, which were generally to coastal, urban areas. However, despite its high urbanization rate, Australia is among the largest countries in the world; therefore its population density is among the lowest in the world.

Life history variation can often reflect differences in age-specific mortality within populations, with the general expectation that reproduction should be shifted away from ages experiencing increased mortality. Investigators of life history in vertebrates frequently focus on the impact of predation, but there is increasing evidence that predation may have unexpected impacts on population density that in turn prompt unexpected changes in life history. There are also other reasons why density might impact life history independently of predation or mortality more generally. We investigated the consequences of predation and density on life history variation among populations of the Pacific leaping blenny, Alticus arnoldorum. This fish from the island of Guam spends its adult life out of the water on rocks in the splash zone, where it is vulnerable to predation and can be expected to be sensitive to changes in population density that impact resource availability. We found populations invested more in reproduction as predation decreased, while growth rate varied primarily in response to population density. These differences in life history among populations are likely plastic given the extensive gene flow among populations revealed by a previous study. The influence of predation and density on life history was unlikely to have operated independently of each other, with predation rate tending to be associated with reduced population densities. Taken together, our results suggest predation and density can have complex influences on life history, and that plastic life history traits could allow populations to persist in new or rapidly changing environments.

An earthquake of magnitude 6.0-6.5 in the Sydney region of Australia is viewed by the global insurance community as one of the top 40 risks it faces worldwide from natural disasters . The high ranking of this perceived risk is due to the high population density, standards of construction and the level of insurance exposure in Sydney. Consequently, earthquake hazard and risk in Sydney is an important issue, and one that requires a focused and detailed study in order for the implications of such an earthquake to be fully understood.The presence of regolith (soils, sediments and weathered rock) can dramatically affect the level of ground shaking experienced during an earthquake. The relatively soft materials that constitute regolith tend to have low seismic velocities that amplify ground shaking during an earthquake, increasing the potential for damage to buildings and other infrastructure in the affected area. Therefore, models of the response of regolith to an earthquake (referred to as site response) form an integral part of any earthquake risk assessment.This report documents a preliminary study of potential ground motion amplification due to the regolith in the Botany area of Sydney, Australia. Botany was chosen due to the presence of a significant thickness of regolith and a high value and concentration of critical infrastructure. This report is intended to highlight the potential for significant levels of amplification within the study area, and draw attention to the need for more work on assessing the actual earthquake risk faced by the Sydney region.In order to determine the amount of ground motion amplification that could be seen in the Botany area, the regolith was classified into a series of four site classes. These regolith site classes are differentiated in terms of geotechnical properties that control ground shaking potential. This classification was based upon published and unpublished geotechnical data as well as seismic velocities obtained by Geoscience Australia. Once geotechnical models were defined for each regolith site class, amplification factors were calculated using a vertically propagating shear wave model. This model accounts for the softening and critical damping of the regolith column during large earthquakes. The results demonstrate that there is significant potential for amplification of ground shaking within the study area. For example, the site class that covers the vast majority of the study area has a maximum amplification factor greater than 3.0 at a fundamental site period of approximately 0.5 s. This period of motion would be expected to strongly affect the structures in the study area.The modelled amplification factors suggest that, should an earthquake impact the area, the potential for high levels of ground shaking would be dramatically increased due to the properties of the local regolith. An earthquake similar to the event experienced in Newcastle in 1989 was simulated, in order to demonstrate the potential amplification effect of the regolith during an earthquake. Whilst this simulation is in no way a full probabilistic risk analysis of the area, it does demonstrate that the amplification of ground shaking could cause response spectral accelerations in excess of 1.0 g, at periods of vibration that would be expected to cause damage to structures in the area.It is important to emphasise that this work is intended to provide a point of focus to initiate discussion rather than be a definitive seismic hazard assessment product. The results have been derived with limited geotechnical data, and without a detailed analysis of the uncertainties present within either the data or the modelling process. Nevertheless, this work does provide a starting point for recognising and addressing the potential risk that earthquakes pose to the study area.

Due to Australia’s size and relatively low population density, domestic travel for a holiday, business, or visiting family and friends often involves long hours of driving or a domestic airline flight. Nevertheless, in the year ended December 2024, Australians spent millions of nights away from home on domestic travel trips, with the strongest accommodation preference being staying with friends or relatives. The second most popular choice of accommodation was at a hotel, resort, motel, or motor inn. Urban centers and surfing spots dominate While Australians enjoy diverse accommodation options, their choice of destinations focuses on major cities and beloved coastal areas. Sydney emerged as the top destination for domestic overnight visitors in 2024, attracting over **** million people. Melbourne and Brisbane also proved popular, along with renowned beach and surfing locations along New South Wales' North and South Coast. Interestingly, Melbourne outpaced Sydney in terms of visitor expenditure, with domestic overnight tourists spending over **** billion Australian dollars in the Victorian capital compared to **** billion in Sydney. Domestic travel motivations The primary motivation for domestic overnight travel in Australia was to go on holiday, accounting for almost ** million trips in 2024. The city of Melbourne snatched Sydney's crown for the second year running as the most popular holiday or leisure destination, with Sydney the previous winner in 2022. Visiting family or friends was the next most common reason for domestic overnight travel, with around ** million trips taken. Business trips came in third, followed by uncategorized visit purposes.

In 2019, Queensland was the Australian state with the highest density of general practitioners with 125.4 GPs per 100,000 of the population. The Australian Capital Territory had the fewest number of GPs in relation to its population.