From toilet-trained calves to eco-friendly glitter, here’s our pick of the year’s weird and wonderful scientific advances. 

Let’s face it, 2021 has been a bit rough. So keeping up with the latest, non-Covid, science news might not have been high on the ol’ priority list. 

So, in case you missed it, or just because you want a boost, here are 10 scientific achievements from the year that’s been.

1. Calves learned to use the potty

Apparently calves are easier to toilet train than infants. 

In the name of reducing greenhouse gases, pollution and water contamination, scientists from Auckland and Germany trained calves to use a MooLoo, a kind of latrine toilet for cows. 

The researchers first fitted calves with a collar that vibrated when they “went” in the wrong place. They also rewarded the calves with food when they walked over to use the MooLoo. After less than a month, three-quarters of the calves were using the loo for most of their wee trips.

According to the scientists, if cows did at least 10 to 20% of their wees in an area like the MooLoo, which would capture the urine before it ran off into soil or streams, it could significantly reduce greenhouse gases. 

2. Finger-clicking figured out

Pretty sure most people have the one awkward friend who can’t click their fingers. Never fear, science is here to help.

Turns out you need just the right amount of friction to store up movement energy (kinetic energy) and then release it to make the “pop” sound. Fingers that are too slippery won’t store up enough energy and those that are too grippy can’t release that pent-up energy. Neither will give you a great snap.

Scientists figured this out by filming people using high-speed cameras as they snapped their fingers and measured the power of their snap using force sensors. 

The researchers also rigged how slippery or squishy a person’s finger was by covering the thumb and middle finger with different materials like a rubber glove with lube or a thimble. In science terms, this changed how much friction and compressibility heir fingers could make.

As well as helping the snap-challenged, the research has a practical application too. It could help biologists understand certain animals with high-speed snaps better, like the Panamanian termite soldier, which snaps its jaws together ultrafast to deter a rival. Plus, understanding the dynamics of the finger snap can help engineers fine tune the movement of prosthetics or make better soft robots with great grip.

3. How a duck learned to swear

Ripper, an Aussie musk duck that lives in the Tidbinbilla Nature Reserve in Canberra, has been heard uttering the phrase “you bloody fool” to try to woo lady ducks. He’s also pretty good at imitating doors slamming.

By recording and analysing these vulgar vocalisations, researchers concluded that Ripper was imitating voices in a similar frequency range (pitch) to human speech, different to the pitch or normal duck quacking.

The researchers think Ripper probably heard and learned the sounds early on in life, similar to how some songbirds learn their melodies.

The reason scientists are so interested in this chatty duck is because it’s quite uncommon for ducks to imitate sounds like this. By studying Ripper and other ducks like him they might get more information about how sound-making evolved in birds.

4. Movies were rated using breath smell

The system for rating movies (G, PG, M, R16 etc) kinda sucks. But scientists might have figured out a better way: use people’s breath to understand how they’re feeling – scared, relaxed or turned on – and use that to determine a rating. 

The idea is, our bodies create chemicals as they go about their business of living and those can change based on how we’re feeling. Those chemicals, called volatile organic compounds, are let off through our breath. If you’re scared, say, you might breathe quicker and give off more CO2. 

Scientists, including a computer scientist from Auckland, first had to do it the other way around. That is, see if the levels of any of those compounds were different for movies that had already been rated. So they hooked a breath-monitoring device (mass spectrometer) up to a cinema’s air filtration system and measured what was coming out.

One compound, called isoprene, matched up pretty well with the ratings for a couple of films. It was lower for kids’ movies and higher in a PG-type film. Isoprene is made when you move around so maybe more suspenseful scenes make people fidget more, letting off more isoprene.

The researchers want others to take their technique and run it on a bunch of other movies to see if it holds up. 

5. Astronomers figured out how old one of the Southern Cross’s stars is

An international team of astronomers has worked out the age and size of Beta Crucis, the second brightest star in the Southern Cross.

It’s a young (relatively in star-speak) 11 million years old and 14.5 times bigger than the sun. 

Beta Crucis is now the heaviest star ever to be measured using a technique called asteroseismology, which looks at how sound waves bounce around inside a star and cause changes in its light. 

6. We’ve bred coral IVF babies for the first time

The world’s first coral IVF babies, corals born by combining coral egg and sperm then growing the babies in floating pens at sea, have now had their own babies “naturally” in the wild. 

Coral IVF is a technique that’s being used to try and restore coral ecosystems that are dying due to climate change. Without enough individuals in a colony, the corals can’t reproduce. By artificially creating and then replanting corals, the colonies should hopefully be able to survive on their own.  

These particular corals were replanted back into the Great Barrier Reef in 2016.

Researchers hope this is the start of restoring reefs worldwide.

7. Archeologists found a new moa skeleton on Rakiura

Bits of a moa skeleton dating back to between 1297 and 1395 were found on West Ruggedy Beach on Rakiura (Stewart Island). 

Researchers think this moa (a South Island giant moa) probably died of natural causes rather than being hunted because it didn’t have any cut marks on the bones and had stains on the bones from its gut contents slowly decomposing (yum).  

The age of the bones also says that this moa was alive when Māori were on the island. Researchers also think there were a few other moa roaming around the island at this time. 

The discovery helps paint a picture of what it was like on Rakiura when humans had first settled there.

8. Scientists partially restored a man’s sight 

Genetically inherited blindness is near-impossible to treat right now. Some inherited forms of blindness can, and have, been treated by fixing faulty genes that make someone slowly start to lose the cells in the eye that pick up light. 

But once those cells are gone, it’s no use tinkering with those genes.

Instead, researchers figured out a way to use pulses of light to control the activity of nerve cells in a blind person and partially restore a man’s sight. 

The technique is called optogenetics and was originally used as a research tool to turn particular genes on and off using light. In this latest feat of scientific awesomeness, doctors bypassed the damaged eye cells and went straight to the nerves (called retinal ganglion cells) that link up the eye with the brain. 

They injected the retinal ganglion cells with the genetic instructions for making a protein that responds to light. They then triggered this protein using light pulses, delivered by a special headset that translates light from the world around us into pulses of amber-coloured light the protein responds to. 

It took time, training and patience and the man who had his sight restored still can’t recognise faces or see all that much. But scientists are hopeful this is the first step towards even better methods that could help more than two million people worldwide who have rare forms of inherited blindness.

9. Kea can use touchscreens but can’t tell what’s real and not

Kea are pretty darn smart. They understand probability, can pick the right tool for a task and now can find their way around a touchscreen with their tongues. 

Auckland researchers taught the birds to use the computers as part of an experiment to see whether kea view the virtual world as the real world, also called being a naïve realist.

In the experiment, kea watched a real ball placed onto a seesaw, which tilted so that the ball would roll into one of two real boxes. If they picked the box the ball went into, they got a reward. The birds did the same task again but with a virtual ball, seesaw and boxes. 

Then the experimenters had a virtual ball-seesaw combo lead to a real-world box. The kea tapped the real boxes, expecting the ball to be in there. 

And as fun as it is to see a kea work an iPad, the study has actual consequences for how animal behaviourists study the birds. It means they could use computers to simulate tasks to test their wits and it would be (in the kea’s mind anyway) the same as in real life. 

Bonus kea story: a bird with a broken beak named Bruce learned to clean himself using pebbles.

10. There’s eco-friendly glitter now

OK, to be fair, I hate glitter. It’s annoying as, and hangs around far too long. 

But for fans of the stuff, you’ll be pleased to know there’s now an eco-friendly version. It’s non-toxic and biodegradable because it’s made of the stuff that plant cell walls are made of, aka cellulose. 

Researchers used a plant called Pollia condensata that makes bright, shiny blue berries. They watered down the cellulose from the berries’ cell walls and poured it onto a flat mould. As the liquid dried, it created microscopic spiral structures. By tweaking the angle of those spirals, scientists could change the colour the cellulose reflected. 

They transformed that into ribbons, which were cut up to make glitter. 

These scientists used the berry pulp but they say you could just as easily use other fruit peels or cotton fibres leftover from fabric-making.