A news story for all of you who have ever dared to suck on a warhead super-sour candy… (And for those who cringe when you see your kids flock to a burst pinata full of sour lolly treats.)

Sour gummies, sour worms, sour patch thingies, sour squirms, sour rainbows, sour bears…

You name it, there’s a super-sour hyper-acidic version of your least favourite (or your kid’s favourite) lolly.

We’ve known for years that these acidic ‘treats’ are a menace for teeth enamel (acid + carbonate, anyone?), and now researchers have confirmed what dare-devil kids have known for years:

Sour stuff increases risk-taking behaviour.

Researchers gave participants a drink of something sour, sweet, umami, salty or bitter. Straight after, they asked people to play a gambling game that involved pumping up a balloon. And there was a catch.

Money or the BANG!

The bigger the balloon, the higher the returns for the participant.

But should the balloon pop, you earned zilch.

When it came to gambling further and risking more, sour was king-kong of flavours.

Those with a sour taste in their mouth pumped the balloon up to 40 times, compared to just 20 or 30 times for other flavours.

So what does this mean in the playground?

It’s hard to say. The participants in the study were in their 20s, on average, so the results may not mean anything when it comes to kids.

But anyone who’s ever dared to suck on a super-sour warhead knows the thrill that comes with facing the pain and exploding your brain.

I’d guess that kind of adrenalin could well lead to other kinds of adrenalin-inducing behaviours…

Sweet advice for risk-takers…

If you’re about to head out lead climbing or race car driving or to a P&C meeting where they’re calling for a new president, maybe skip the margaritas. Stick to something sweet instead 🙂

If you could design your own robot, what would it be? Would you create something to tidy the house? Drive the car? Or hand you flat whites while you luxuriate on the couch with a great book? (Clearly, I vote for option 3.)

But there is another option: use modern technology for something really worthwhile. Like koala conservation…

Image: Queensland University of Technology

Flying robots with heat-sensing eyes can find koalas, even in thick bush.

The unmanned robots, called drones, look like giant flying spiders, and they’re part of an effort to help save koalas in the wild.

Researchers on the ground control the drones, which fly high above the bushland to find and count koalas much faster than humans can.

“I’m pretty good at spotting koalas,” grins Associate Professor Felipe Gonzalez, who leads the Queensland University of Technology project. “But I’m nowhere near as good as a drone.”

Where a team of experts might take two hours to search for koalas in an area of forest, a drone can cover the same area in just 20 minutes.

“When we have a better idea of where koalas are, and how many we have, we can use that information to plan conservation efforts and make decisions,” says Associate Professor Gonzalez.

Eyes in the sky

Image: Associate Professor Felipe Gonzalez, QUT

The helicopter-style drones are programmed to fly over forests “in a lawnmowing pattern”, so they don’t miss a single tree.

They can spot a koala from 20 metres away, so they don’t scare the animals either.

Each drone carries a camera that can sense the heat produced by a koala’s warm body. Remotely controlled, the cameras can twist and turn to offer researchers the best view.

Unmanned flying drones have been around for years, but Associate Professor Gonzalez says the ones being developed at QUT are “unique”.

“They use artificial intelligence,” he explains. “They’ve learned to tell the difference between a koala and other animals by the size and shape of the hot spot.”

Artificial intelligence, or AI, is a form of machine learning. It means the computers on-board the drone can train themselves—by trying and failing and learning from their failures—to correctly identify koalas.

Maths meets environment

An aerospace engineer by training, Associate Professor Gonzalez says making flying robots is a natural combination of his skills in maths and engineering and his life-long love of the environment.

“Ever since I was a kid, I’ve always been interested in animals and ecology,” he says.

He wants to use the drones to monitor other animals in the wild.

“We’re hoping to use this technology to track dingoes, on Fraser Island,” he says.

“We can also use it for wild dogs and feral cats.”

Image: Dr Viviana Gonzalez 

Koala conservation

The number of koalas in the wild is decreasing: the Australian Koala Foundation estimates there are only between 43,000 and 100,000 wild koalas left.

Koalas live in woodland and suburban areas in New South Wales, Victoria and South Australia, and are classified as endangered in Queensland.

The drones are being trialled in South East Queensland, where wild koalas must share their habitat with a growing human population.

This story first appeared in Crinkling News.

Next time you discover a mummified corpse, you’ll know who to call…

Ever wonder how carbon dating works? Or how scientists can tell how old something is, just by testing the dirt they found it in?

Well, wonder no more. Below is my article on carbon detective Dr Stewart Fallon, an ANU expert on carbon dating. It first appeared in the magnificent Crinkling News.

Carbon sleuths solve 5,000-year-old crimes

Dr Stewart Fallon is a carbon detective. By measuring how much carbon is in a once-living thing—whether it’s charcoal, shellfish, coral or bone—Dr Fallon can work out when that thing was last alive.

“We can measure back to about 50,000 years,” says Dr Fallon, who works with a team at the Australian National University.

The method is called carbon dating, and Dr Fallon uses it to help solve mysteries, fight crime, and better understand our environment.

Mysterious bones

In 2016, a human jaw bone, leg bone and arm bone were found in a Brisbane park. The police asked Dr Fallon to carbon-date the jaw bone.

Carbon levels in the bone showed it wasn’t a recent murder: the person probably died between 1800 and 1899.

Corals and ivory

Dr Fallon also uses carbon dating on coral reefs. “Corals can live for several hundred years, and have growth rings, just like trees do,” he says. “We’ve dated some deep sea black corals that have been living for 4500 years.”

Horns and tusks can also be dated, helping police work out when the animal died. “We do a lot of work with police on wildlife forensics, trying to help prevent the illegal trade in rhino horn and ivory,” says Dr Fallon.

Ötzi the Iceman

In 1991, after a warm summer melted mountain ice, hikers discovered the mummified remains of a human body, now nicknamed Ötzi the Iceman.

Carbon dating showed Ötzi died more than 5000 years ago. “He was almost perfectly preserved, he’d been covered with ice for a long time,” says Dr Fallon. “They were able to date food in his stomach, and the grass his shoes were made from.”

What are carbon atoms?

Everything is built of tiny packages, called atoms. And every living (or once-living) thing—whether it’s your lunch, your goldfish, or your bones—contains atoms of carbon. Even the air we breathe contains carbon atoms, bound up in carbon dioxide gas. But not all carbon atoms are the same:

¹²C: More than 98% of carbon atoms contain 12 particles in their central nucleus. We call this carbon-12.

¹³C: Nearly 1.1% of carbon atoms are slightly heavier than carbon-12. They’re called carbon-13, because their nucleus contains 13 particles.

¹⁴C: A teensy-tiny percentage of carbon atoms are heavier still, with 14 particles in their nucleus. These carbon-14 atoms are so heavy, they sometimes fall apart. When this happens, they ‘disappear’, decaying into nitrogen atoms instead.

How does carbon dating work?

The number of ¹⁴C atoms compared to ¹²C atoms is called the ¹⁴C to ¹²C ratio.

• While you’re alive: The ¹⁴C to ¹²C ratio in your body is the same as in the air. You add some ¹⁴C when you eat and breathe, and you lose some ¹⁴C when it decays, so the overall level stays the same.
• Once you’re dead: You can’t add more ¹⁴C (because you’re dead, so you can’t eat or breathe). But the ¹⁴C in your body can still decay. We know it takes 5730 years for half of your ¹⁴C to disappear. This means we can use ¹⁴C levels as a kind of clock
• The deadly difference: Because your ¹⁴C has been disappearing, the ¹⁴C to ¹²C ratio in your dead body will be different to the ratio in the air. This difference allows Dr Fallon to work out how long you’ve been dead.

History in the air

The ratio of ¹⁴C to ¹²C in the air is always changing. For example, the nuclear weapons tests that happened from 1955–1963 temporarily doubled ¹⁴C levels.

On the other hand, burning fossil fuels releases loads of carbon, but hardly any of it is ¹⁴C. Fossil fuels are so old that all of their ¹⁴C has decayed, Dr Fallon says.

We’re just back from a long weekend of family camping. It was loads of fun, and exciting too, because it was WET. We camped through Perth’s first real rains for the year, and within hours of them falling, our tent site (and the toilet block) was full of tiny frogs. HOW AWESOME!!

Want to know what sort of frogs they were? Well, grab your phone and start recording. Whether it’s a ribbet, croak, chirp or trill, a frog’s call can be used to identify it.

That’s the idea behind FrogID, a free app launched by Dr Jodi Rowley, a frog expert at the Australian Museum.

“FrogID is an attempt to get an army of frog biologists out there, young and old, reporting where frogs are,” says Dr Jodi Rowley, frog expert at the Australian Museum.

“We have 240 native frog species in Australia, but we don’t really know how they’re distributed, or how they’re doing.”

Since its launch, more than 20,000 frog calls have been recorded using the app!

Join the FrogID army

Discovering which frogs live in your area is as simple as waiting near a wetland, pond, dam or creek, or even in your backyard.

“The best time is just after dark, and if it has rained recently, it’s even better,” says Dr Rowley.

When you hear a frog, use the app to record its call. You then match the call with the calls of frogs likely to be in your area, and send your best guess to the Australian Museum.

“You’ll get a notification about whether your guess was right or wrong, and you’ll get better at identifying the frogs in your area,” says Dr Rowley.

The app is paired with a website that allows you to join groups and compete with other schools.

What is citizen science?

FrogID is a citizen science project. That means it’s a hands-on research project that scientists and volunteers work on together.

It’s not easy being green

Dr Jodi Rowley hopes FrogID will encourage all Australians to get involved with helping to save Australia’s native frogs. Image: Stuart Humphreys

Dr Rowley wasn’t always a lover of frogs. “I was quite a city girl, my parents didn’t take me camping. It wasn’t until I studied environmental science that I even began to realise frogs were out there.”

Now she’s discovered just how fragile frogs are. “Frogs are amazing, gorgeous, precious things that really need our help,” she says. “FrogID is a bit of a rescue mission…we need information to help them.”

Your FrogID reports will be used to track where frogs are found, how populations are changing, and to discover new populations of threatened species. “This is a cool way to monitor frogs just by listening to their calls,” Dr Rowley says. “We may even discover new species.”

Top 5 frogs to spot

The frogs you hear depend a lot on where you are, Dr Rowley says. They’re also more active during summer and spring, so now’s a great time to get out there. Her top 5 frogs to spot are:

Striped marsh frog (Limnodynastes peronii): Around 6 cm long and common along the East coast. They make a ‘bok, bok, bok’ noise, like a tennis ball being hit.

Common Eastern froglet (Crinia signifera): Around 2–3 cm long and common along the East coast. They make a ‘crick, crick, crick’ call, a bit like a cricket.

Green tree frog (Litoria caerulea):  A large frog (12 cm) found in all states except Tasmania and Victoria. Also known as the dunny frog as you can often find them in outback toilets.

Peron’s tree frog (Litoria peroni): A colour-changing frog (5 cm) found in northern Victoria, New South Wales and southern Queensland. Has a cackling, drill-like call.

Motorbike frog (Litoria moorei): A large frog (up to 14 cm) found in pools and backyards in south-west Australia. Named for the male frog’s call, which sounds like a motorbike changing gears.

Cane toad alert

Our native frogs are often confused with the cane toad—a poisonous pest. “It’s the only toad we have in Australia, and that’s our fault, we introduced them,” says Dr Rowley. “FrogID will also help us track the cane toad invasion, and how they’re moving across Australia.”

Cane toad (Rhinella marina): A warty 10–15 cm toad, found across north and south America—and spreading out in Australia. “The cane toad has a constant trill that goes on and on… None of our native frogs sound like that.”

This article first appeared in Crinkling News. The frogs-in-the-toilet-block happened yesterday 🙂