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Australia’s Ebola Risk

Credit: CDC/Cynthia Goldsmith

Credit: CDC/Cynthia Goldsmith

By Robert Cope, Joshua Ross & Phillip Cassey

Improving outbreak control in West Africa resulted in reduced risk to Australia.

In March 2014, the World Health Organization declared an Ebola outbreak in Guinea, West Africa. The outbreak gained global media attention when healthcare workers from the US and UK were infected in August, and after infected individuals entered the US and Spain during October. These events stimulated much debate in Australia about the country’s response.

Crowded Space: The Problem of Orbital Debris

In 2001, the third stage of a Delta 2 rocket re-entered the atmosphere over the Middle East. The titanium motor casing, weighing about 70 kg, landed in Saudi Arabia about 240 km from the capital of Riyadh.

In 2001, the third stage of a Delta 2 rocket re-entered the atmosphere over the Middle East. The titanium motor casing, weighing about 70 kg, landed in Saudi Arabia about 240 km from the capital of Riyadh.

By Kerrie Dougherty

The orbiting detritus of humanity’s exploration and exploitation of space poses a growing threat to operational space systems and crewed spaceflight activities.

The 2013 space thriller film Gravity, in which two astronauts become stranded in space after a cloud of fragments from an exploded satellite destroys their space shuttle, vividly depicts one of the major issues impacting on current and future space activities – the problem of “space junk”, or orbital debris.

Mother Knows Best

An adult female green turtle returning to the sea after nesting.

An adult female green turtle returning to the sea after nesting. Photo: T. Franciscus Scheelings

By Anthony Rafferty

Why do turtles lay eggs when their close relatives evolved live birth? A study of their reproductive physiology reveals how egg-laying improves the survival prospects of hatchlings.

Turtle embryos stop developing inside their eggs at just a few days old – when they are still inside the mother’s reproductive tract. They only start growing again after the eggs are laid.

By careful studies in both freshwater and marine turtles, we have found that this strategy gives turtle mothers the flexibility to choose when and where to lay their eggs for the best chances of survival of their young. What’s more, we have been able to work out how they do it.

The Evolution of Live Birth

The World’s Oldest and Most Accurate Trigonometry Table

Daniel Mansfield holds the Plimpton 322 tablet at the Rare Book and Manuscript Library at Columbia University in New York. Credit: Andrew Kelly/UNSW

Daniel Mansfield holds the Plimpton 322 tablet at the Rare Book and Manuscript Library at Columbia University in New York. Credit: Andrew Kelly/UNSW

By Daniel Mansfield

By decoding an ancient stone tablet, researchers have realised that the Babylonians employed a form of trigonometry that is very different to our own.

Plimpton 322 is one of the most famous tablets from the Old Babylonian period (19th–16th century BCE). It was obtained, perhaps illegally, in the southern Iraq desert where it found its way into the hands of Edgar Banks (the inspiration for the fictional character Indiana Jones).

In about 1922 Banks sold the tablet to the famous publisher and antiquities collector George Arthur Plimpton. Shortly before his death, Plimpton bequeathed his entire collection to the University of Columbia, where the artefact known as “Plimpton 322” remains today.

In Living Colour

Credit: Roy Caldwell

Two mantis shrimp wrestling. These animals have the most comprehensive set of colour receptors known to humans. Credit: Roy Caldwell

By Noor Gillani

Colour perception is more advanced in goldfish than humans, yet researchers have tended to focus on vision in animals similar to us. Justin Marshall says this is “fundamentally stupid” and is setting his sights on a marine creature with 12 different colour receptors.

Humans may have come a long way in their use of colour since the days of finger-painting, but we will never see it the same way creatures of the deep do. Prof Justin Marshall of the Queensland Brain Institute says that most animals live in a world more colourful than the human one. “We think that we’re quite good with colours,” he says. “Some humans will tell you we’ve got the best colour vision in the world.

“We don’t,” he adds. “Most of the other animals out there have better colour vision than we do. Even things like goldfish.”

Tasty Treats Diminish Our Capacity for Patience

Credit: tawanlubfah/Adobe

Credit: tawanlubfah/Adobe

By Bowen Fung

A new study finds that our recent experience with rewards such as food can change our capacity for patience.

In everyday life, we often make commitments to long-term goals, but in many cases we break these commitments (sometimes rather quickly). When we diet, make financial investments or try to quit smoking, it can feel like there is a constant temptation to give up and appease our more immediate desires. This kind of impulsivity – the tendency to act impatiently, without regard for the future consequences – is often considered to be a negative trait, and society praises individuals who display persistence in the face of temptation. After all, we all know that patience is a virtue.

Like, Comment, Share: Should You Share Your Genetic Data Online?

Credit: kentoh/adobe

Credit: kentoh/adobe

By Kathleen Gray

The culture of sharing our private details online is extending to health and ancestry data generated by genome testing. What are the benefits and what are the risks?

Sharing your personal facts and feelings with friends and strangers is a way of life for many people in online social networks. Think about the increase from one million to one billion Facebook users over the past decade, and the many other social media sites that have hundreds of millions of users. But who would want to share their personal genomic data this way, and why?

Testing Times

Egg Supply and Demand

Credit: Maridav/Adobe

Credit: Maridav/Adobe

By Karla Hutt & Jock Findlay

Understanding the relationship between the number of healthy eggs stored in the ovaries and the length of the fertile lifespan will lead to more accurate predictions about how long each woman will remain fertile.

Globally, more women over the age of 30 are giving birth than in any previous generation. In fact, one in seven Australian women have their first child at 35 years of age or older. Considering our grandmothers usually had their first birth in their early twenties, this is a dramatic change.

How Zombies Can Save Us from a Real Apocalypse

How Zombies Can Save Us from a Real Apocalypse

By Nick Beeton, Alexander Hoare & Brody Walker

Mathematical modelling of a zombie apocalypse has real-world applications in our responses to infectious diseases such as Ebola and HIV, wildlife conservation and even the teaching of statistics.

Zombies are big right now. They’re on your TV screens (The Walking Dead), in your computer games (Plants vs. Zombies) and have even snuck into classic literature via such books as Pride and Prejudice and Zombies. They’ve become one of those internet memes that just won’t die; people seem ready to squeeze them into every conceivable situation.

James Randi: An Honest Liar

James Randi

James Randi has used his remarkable conjuring skills and the power of his personality and intellect to show us how easily we can be deceived.

By Peter Bowditch

James Randi discusses his greatest achievements, disappointments, what woo annoys him the most, and the challenges fracturing the skeptical movement.

As a professional magician and debunker of nonsense, James Randi has long been one of the most significant public figures in the world of organised skepticism and rationality.