Australasian Science: Australia's authority on science since 1938

Cover Story

Cover Story

On the Crest of a Gravity Wave

Credit:Henning Dalhoff / Science Photo Library

Credit:Henning Dalhoff / Science Photo Library

By Stephen Luntz

Gravitational wave detectors may soon provide a new way of viewing the universe, but Australia has passed up the chance to have one located here – for now at least.

The recent detection of the Higgs boson represented the final frontier for the Standard Model of Particle Physics, for once putting science on the front page of the world's newspapers.

The search for the Higgs boson parallels the quest to detect gravitational waves, a key feature of General Relativity. Both require enormous facilities to detect something both subtle and hugely significant, and in both cases it is hoped that their discovery will be simply the first step to far greater insight into the workings of the universe.

The Earth’s First Super-Predators

Anomalocaris

Spanning 1 metre in length, the Cambrian super-predator Anomalocaris patrolled the world’s oceans more than half a billion years ago. Credit: Katrina Kenny

By Allison Daley & John Paterson

The discovery of the world’s oldest apex predators in the oceans more than half a billion years ago is a puzzling story that began well over a century ago. We now have a much clearer picture of these spectacular animals, but the debate about their feeding habits continues.

The classic Australian cliché to “throw another shrimp on the barbie” may well have an origin that dates back much further than expected – to the Cambrian Period over 500 million years ago.

Allison Daley is a postdoctoral researcher at the Natural History Museum in London. John Paterson is a Senior Lecturer at the University of New England in Armidale, NSW.

Losing Weight Subconsciously

The sympathetic nervous system subconsciously regulates blood pressure, metabolism, digestion, respiration and body temperature.

The sympathetic nervous system subconsciously regulates blood pressure, metabolism, digestion, respiration and body temperature.

By Nora Straznicky & Elisabeth Lambert

Individuals vary widely in their ability to lose weight, with new evidence suggesting that up to 45% of the variability in weight loss is caused by individual differences in subconscious nerve activity.

Sixty per cent of adult Australians are either overweight or obese, and thus at increased risk of serious diseases such as type 2 diabetes, heart disease and cancer. On both individual and societal levels, excess body weight has far-reaching ramifications on quality of life, life expectancy and healthcare costs, making it a modern public health challenge.

Nora Straznicky and Elisabeth Lambert are research scientists in the Baker IDI Heart & Diabetes Institute’s Human Neurotransmitters Laboratory.

Out of Asia

Credit: Jamie Tufrey

Credit: Jamie Tufrey

By Sue O’Connor

The discovery of ancient fish hooks and the bones of offshore fish species reveals that the people living to the north of Australia more than 50,000 years ago had the maritime skills and equipment necessary to reach Australia.

Some time prior to 50,000 years ago, modern humans left mainland Asia (Sunda) and began the first of a series of maritime voyages that was to culminate in the colonisation of Sahul (Australia and New Guinea). This was a remarkable accomplishment at this early date, and demonstrates the capacity for complex planning and technological innovation that has become the hallmark of our species.

Sue O’Connor is Professor of Archaeology and Natural History at The Australian National University.

Botulism Paralysed

Botox injection

Botox acts by paralysing small groups of muscles when injected in the face.

By Callista Harper & Frederic A. Meunier

A new class of inhibitors could prevent infection by a neurotoxin classified as a Category A biological weapon.

While the origins of botulism lie in food poisoning caused by contaminated sausages, it is probably best known under its commercial name Botox, which is used in cosmetics to smoothen wrinkles.

However, what is not widely advertised is that botulinum neurotoxin is an incredibly deadly agent capable of killing several million people with just 1 gram. For this reason it is a potential bioterrorist threat, with the USA’s Homeland Security classing it as a Category A biological weapon.

A/Prof Frederic A. Meunier is a NHMRC Senior Research Fellow and head of the Neuronal Trafficking Laboratory at the Queensland Brain Institute, University of Queensland. Callista Harper is a PhD student in his group.

The Right Dose

Ethnic differences can have a significant impact on how people respond to drugs.

Ethnic differences in cooking styles, contraception, smoking, and caffeine and alcohol consumption can have a significant impact on how people respond to drugs.

By Vidya Perera & Andrew McLachlan

Diet and lifestyle are rarely considered when assessing how people respond differently to drugs, yet ethnic differences in cooking styles, contraception, smoking, and caffeine and alcohol consumption can have a significant impact – especially in treatments for mental health.

If the same dose of the same drug is given to a group of people, no two responses will be the same – even among identical twins. As Sir William Osler (1849–1919), a famous physician and researcher, stated: “Variability is the law of life, and as no two faces are the same, so no two bodies are alike, and no two individuals react alike and behave alike”.

Vidya Perera is a doctoral student at the University of Sydney’s Faculty of Pharmacy. Professor Andrew McLachlan is Associate Dean of Research at the University of Sydney’s Faculty of Pharmacy, and Chair of Pharmacy (Aged Care) at Concord Hospital.

Is It a Bird or a Dinosaur?

Archaeopteryx

Is it a bird? Is it a dinosaur? The exact position of Archaeopteryx in the evolutionary tree remains debated. Main Illustration by Nobumichi Tamura. Inset photo by Michael Lee

By Michael Lee

As a new specimen of Archaeopteryx is unveiled, scientists argue whether this famous creature is a true bird or just another bird-like dinosaur.

As one of the most famous fossil animals, and an icon of evolution, Archaeopteryx has long attracted attention and controversy. The discovery in 1861 of a creature with the wings and feathers of a bird, but the tail and teeth of a reptile, could not have been more timely: only 2 years earlier, Charles Darwin’s theory of evolution had predicted such “missing links”. Archaeopteryx exemplified the evolutionary process caught in the act.

Michael Lee is senior research scientist at the South Australian Museum and the University of Adelaide.

Artificial Photosynthesis: Feeding and Fuelling the Future

iStockphoto

Image: iStockphoto

By Thomas Faunce

A global scientific project using nanotechnology and synthetic biology to re-engineer photosynthesis may help solve our energy, food, water and greenhouse gas problems.

Nanotechnology has been one of the most hyped terms used in science over the past decade, but the toxicological risks of various forms of nanotechnology have also caused concern. Examples have included nanoparticle forms of zinc oxide and titanium dioxide to make sunscreens that were not only effective in repelling unwanted solar radiation but also more cosmetically appealing. However, my own research revealed that one sunscreen released onto the Australian market, and never officially recalled, degraded steel roofing when accidentally applied by workmen.

A/Prof Thomas Faunce is an Australian Research Council Future Fellow at the Australian National University. He was the scientific and administrative coordinator of the first international conference dedicated to creating a Global Artificial Photosynthesis project at Lord Howe Island in August 2011.

How Was the Universe Born?

The universe in an hourglass

Image: iStockphoto

By Geraint Lewis

Modern cosmology tells us that the universe as we know it arose 13.7 billion years ago in the fiery birth of the Big Bang, but our understanding of the laws of physics is incomplete and we are currently unable to answer the questions of where the universe actually came from. Cosmologists have many ideas, ranging from the reasonably strange to the extremely outlandish.

For much of human history we were confident about the purpose of the universe, with the Bible telling us that it was born only a few thousand years ago and that it exists as a stage for humans to play out their physical existence before moving onto a more ethereal realm.

Geraint Lewis is Professor of Astrophysics at The University of Sydney.

How HIV Hides in the Brain

HIV-positive people are particularly susceptible to the early onset of dementia.

HIV-positive people are particularly susceptible to the early onset of dementia. Credit: Mehau Kulyk/Science Photo Library

By Lachlan Gray

With the introduction of the latest drugs and treatments, infection with HIV no longer represents a death sentence. However, HIV-positive people are particularly susceptible to the early onset of dementia and several other conditions of ageing, such as cardiovascular disease, frailty, cancers and bone disease. New research has found that when the HIV virus gets into the brain, it infects a key cell type, the astrocyte, leading to its dysfunction. This, in turn, triggers the development of HIV dementia, and at the same time provides HIV with a hideout where it is protected from the immune system and antiviral drugs.

The human immunodeficiency virus (HIV) infects the cells of the immune system, rendering the body defenceless to opportunistic infections and cancers and ultimately leading to the development of acquired immunodeficiency syndrome (AIDS) and the death of the patient. HIV is a blood-borne virus, and is predominantly transmitted via the exchange of bodily fluids during sexual contact, sharing of contaminated needles, and during pregnancy and breastfeeding.

Lachlan Gray is a Postdoctoral Research Fellow at the Burnet Institute and Monash University.