My new book, A Doctor Across Borders: Raphael Cilento and Public Health from Empire to the United Nations (Canberra: ANU Press, 2019), took a long time to emerge.

AUSTRALIA’S POPULATION HITS 25 MILLION EARLIER THAN EXPECTED

By Fran Molloy, NYU Sydney Lecturer in Journalism

On August 7, Australia’s population reached 25 million, more than two decades faster than predicted.

Recently, the Australian Bureau of Statistics population clock – which adds another Australian every 1 minute and 23 seconds – rolled over to exactly 25 million.

It’s a significant benchmark, particularly when as recently as 2002, Australia’s population was predicted to climb from 19.6 million in 2002, to 25.3 million in 2042.

Instead, Australia’s already at 25 million, more than two decades earlier than expected; and if current trends continue, will likely exceed 30 million by 2030.

“When population grows rapidly, it makes it more likely that you will have further growth in the near future, because you have a younger and more fertile population,” says Professor Nick Parr, from Macquarie’s Centre for Workforce Futures.

He points out that population growth is complex; while migration has played a huge role in for Australia’s fast growth over the last couple of decades, factors like a strong economy pre-2008 and delayed childbearing also contributed to a “baby bump” in the early years of this century.

Students + Kiwis + holiday workers + expats + babies = 25 million

In 2017, net migration accounted for 62 per cent of our population increase. “That number includes international students as well as temporary workers, working holiday makers, New Zealanders and returning expatriates,” says Parr.

With house prices recently spiralling in major cities and complaints of traffic congestion and overdevelopment growing louder, rapid population growth is generally unpopular among Australians.

But there are advantages, Parr says – chief among them that population growth due to immigration both supports our ageing residents – and slows the overall rate of ageing of our population.

“When we have more people working and contributing taxes, the costs of population ageing are spread more widely,” he says.

He says that a more pressing issue for Australia than population growth, is its distribution. “Geographically, our population growth is very heavily concentrated in the major cities, which is the key factor influencing congestion and housing issues.”

What’s next? “Our population will continue to grow, and we need to plan for that as best we can,” he says. “We need to look further into the future to ensure today’s children are educated and trained in areas that would be gainfully used in the labour market, so they help defray the costs of population aging and contribute to tax dollars.”

This article has been republished with the permission of The Lighthouse, Macquarie University’s multimedia news platform.

This post comes to us from NYU Sydney Instructor Adam Gall, who teaches Australian Environmental History. 

We tend to see ants as objects of benign curiosity or perhaps annoying interlopers in our gardens or kitchens, but when the Argentine ant appeared in Australian cities and suburbs in the mid-twentieth century it was already understood as a significant pest species. These unassuming little brown ants were emerging at the time as a global problem, infesting people’s home in large numbers in Mediterranean Europe and the southern United States, and generating a great deal of attention among scientists and policymakers. They likely arrived in Australia via the global shipping networks that connected this country with the rest of the world, though their exact date of arrival remains uncertain. As they traveled to new places, they went through a population bottleneck. Instead of being surrounded by diverse, rival colonies of the same species (as they had been in their home range in northern Argentina), Argentine ants in Australia were part of one group and able to cooperate against native species and compete with them for food resources. Their arrival prompted an enormous effort to control their numbers and, in Sydney at least, to eradicate the ants entirely using pesticides.

In a new chapter, “On the ant frontier”, written for a forthcoming edited collection, Animals Count, I narrate the history of these creatures in Sydney. The focus of my research has been on records left by the Argentine Ant Eradication Committee, the government organ which oversaw the eradication initiative in New South Wales. These files are held in the State Archives in western Sydney, at a compound situated on the rural fringes of the metropolitan area. They contain all sorts of documents, including weekly reports from field officers, invoices for equipment, letters from members of the public, articles and pamphlets, as well as plans for publicity campaigns. At the forefront of the work were entomologists, the insect scientists who developed techniques for identifying and spraying Argentine ant nests, and their reports and expert contributions have been fascinating to dig into, too.

The fact that the ants were domestic pests put the campaign on a collision course with suburban middle-class people and their growing awareness of the environmental effects of organochlorine pesticides. Already in the 1960s there were household pets affected by chlordane spray, and people complained about this to the Committee and sought compensation. There are even stories of citizens standing in front of the spraying carts or refusing access to their land because they recognised–against the official positions of government and chemical companies–that these were dangerous poisons. This is all part of a global history, too: around the world, more and more citizens and activists tried to prevent the use of organochlorine pesticides, partly because of the influence of Rachel Carson’s powerful writing in The Silent Spring. There pesticides were used because they were seen as more environmentally friendly than other chemicals, and the eradication campaign was undertaken to protect people’s sense of everyday wellbeing and household amenity. Eventually, citizens and their representatives in the northern suburbs of Sydney–particularly in leafy Lane Cove–challenged the right of the ant unit to spray. In 1985 the campaign was formally ended by the state government, though the ants themselves are still seen as a huge threat to biodiversity in many places around the world.

I found this journey through the archives very interesting as a historical researcher, because it had a defamiliarising effect on the spaces of my everyday life. I grew up in this city in the 1980s and 1990s and had never heard about Argentine ants before beginning this work. I found that whenever I mentioned my topic to people I met, they would say things like ‘Oh, I remember the TV ads!’ and talk about the Trapper Tom character, and about collecting samples to send in to their local councils as kids. There is a whole submerged history of ordinary people–particularly those who were children in Sydney during the 1960s and 1970s–being really invested in the campaign against the ants through popular media.

As new campaigns begin against other species, such as fire ants in Queensland, it is fascinating to see patterns repeating. History prompts us to ask difficult questions about the decisions we are making now. While it is happening, we feel with great urgency the threat of insects infesting our homes or suburban spaces. But we should also recognise that there is usually much more going on, from the effects of changes to land use to the potential risks of whatever substances we use to control pest species.

This post comes to us from NYU Sydney biology instructor Sean Blamires. He also took the photographs. His research was the focus of the film Sixteen Legs.

Hickmania troglodytes spider

On Sunday, March 18, the documentary movie Sixteen Legs premiered in Sydney. Earlier in March, New York University students got rare behind the scenes glances at the making of the documentary and a chance to meet the director, Niall Doran.

The movie is an interlinking journey across the Tasmania culminating in rare footage of giant cave spider mating behaviours and is well worth a look. The novelty of the film is its intertwining themes that combine tourism, education, art, natural history, science fiction and fantasy. While an impressive compendium of celebrities, comedians, and scientists appear in the film, the star is unquestionably the cave spider itself, Hickmania troglodytes.

With a leg-span of up to 18 centimetres, Hickmania troglodytes is an intriguing animal on many levels. It has an evolutionary history dating over 100 million years, as such it has outlived the dinosaurs. It has a lifespan of over ten years, which is rare among spiders. Being a troglophile it spends its life in caves but can survive outside if it needs to. H. troglodytes belongs to the Family Austrochilidae. H. troglodytes is found only in Tasmania, while all other extant members reside in Chile. The Austrochilidae is of particular interest to Arachnologists because they are thought to represent the nexus between modern ‘true’, web building, spiders (the ‘Araneomorphs’) and more ancient non-web builders (the ‘Mygalomorphs’). Add to all of this H. troglodytes has a slow but deliberated, complex, and measured copulation behaviour, involving males tapping female’s heads, kinked forelegs, spider bondage, contortionism, and even cannibalism, all over the course of several hours.

A web in a cave under torch light. This distinctly shows the cribellate silks as they appear blue in this light

While this animal’s sexual exploits are undoubtedly impressive, my interest is in its massive horizontal sheet web and the types of silk it uses to construct it. My collaborators (including Niall Doran) and I have examined the main structural silks in H. troglodytes web and found that larger, older, spiders use tougher silks. We presume this is because the web needs to support the larger spider’s mass or that the webs of larger spiders catch bigger prey.

To capture insects in their webs modern spiders can make their capture threads sticky by using a type of silken (aggregate) glue, while more ancient spiders, such as H. troglodytes, secrete bundles of fine silk threads called cribellate silk to entangle prey. Interestingly, cribellar silk is thought lose its adhesion in humid environments. However, the cave environments where H. troglodytes builds their webs often have humidities exceeding 95%. We are therefore investigating how their cribellate silks can withstand moisture and whether water might even enhance their silk’s stickiness.

There are other projects on this spider and in Tasmanian caves in the pipeline, which we are keen pursue. We plan to one day take New York University students on our expeditions.

Reference:

Piorkowski, D., Blamires, S.J., Doran, N., Liao, C.P., Wu, C.L. & Tso, I.M. 2018. Ontogenetic shift towards stronger, tougher silk in a web building cave spider. Journal of Zoology. 304: 81-89.