Cuckoo forgeries – a bird’s eye view

Cuculus canorus vogelartinfo chris romeiks CHR0791Furry Logic physics hits January’s Physics World magazine with my feature on the lengths some cuckoos will go to trick foster parents into rearing their young. And why other cuckoos don’t bother. Read the full article in PDF form for free.

Huge thanks to Martin Stevens of the University of Exeter, UK, and Cassie Stoddard of Princeton University, US, for generously sharing their vast knowledge of cuckoo vision.

 

Can wildlife films convince us to save nature?

by Liz Kalaugher

A pack of African wild dogs closes in on a wildebeest, racing across the plains at up to 40 km per hour. The lead dog is tiring but a youngster behind powers ahead and snaps at the wildebeest’s hind-legs. Risking broken jaws, the dogs must kill before their prey reaches the safety of its herd. As Keith Scholey of Silverback Films revealed at the Richard Gregory Memorial Lecture on Tuesday, this scene from BBC wildlife documentary The Hunt couldn’t have reached us without the Cineflex kit that stabilises cameras when fixed onto a helicopter, a jeep, a boat or even an elephant.

It’s not all about the equipment, though. “You need a good operator for that technology too, that’s where the art comes in,” former BBC producer Scholey told an audience at the University of Bristol made up of the public and natural history film-makers in town for the Wildscreen Festival.

Science and technology help filming a great deal, by reducing camera vibration, enabling divers to stay underwater longer using rebreathers rather than SCUBA kit, or bringing us high dynamic range TVs that in two or three years’ time will have the brightness and colour we perceive in nature. Wildlife film-makers often turn to biologists too, to discover how animals behave or even where to find them. When Scholey’s colleague Alastair Fothergill wanted to film killer whales teaming up to make waves that wash their prey into danger, he turned to satellite-tracking experts John Durban and Robert Pitman of NOAA Fisheries in the US. Killer whales migrate such long distances that, before satellite tags, it was almost impossible to be in the right place at the right time to capture their actions.

The result? The first footage – in Frozen Planet – of orca using water power to knock a seal off an ice floe into the ocean, and a clip in The Hunt of a pod thwarted in their attempts to wash a humpback whale calf from the safe swimming spot above its mother’s back by the arrival of two “escort” male humpbacks. For many years, divers alongside female humpback whales had known to expect a less friendly male to turn up; the shots revealed why the males do this.

As Scholey explained, orca have only recently resumed hunting humpback whale calves, whose numbers have crept back up following the whaling ban. Since 1985, the ocean off Hawaii has seen 10% more humpback whales each year. Other conservation efforts have had less success. The ban on the ivory trade worked until the sale of stockpiles of legal ivory; now elephant poaching is as bad as it was before. Yet Scholey is hopeful that we can protect the elephant once more, adding that The Ivory Game is the best wildlife conservation film he’s ever seen.

Hidden change

There’s more to this than crisis, however. “I’m passionate about elephants, don’t get me wrong, but I’m more worried about the slow insidious changes,” Scholey said. In his lifetime, one-fifth of coral reefs have vanished and a further fifth are in a desperate state. By protecting 40% of each reef area with marine parks we can restore coral reefs – the zones act as breeding grounds for the large fish that keep the reef healthy but are removed by fishing. This habitat protection would work until 2050. Then ocean acidification is likely to kick in. The 30 billion tonnes of carbon dioxide we release into the atmosphere each year, through activities like burning fossil fuels, also dissolves in the ocean, boosting its acidity. This is bad news for corals, which have calcium carbonate shells that become harder to make as seawater grows more acidic.

Not only is this harming the oceans but the extra carbon dioxide in the air pushes up temperatures around the globe. “We are squeezing the natural world into a tight bottleneck,” Scholey said. Yet film-makers haven’t told us about these issues and the solutions well enough. “It has to stay entertaining enough for enough people to watch it but…you have to communicate the problems as well,” Scholey added. “We can communicate crisis but insidious change is difficult. Time is running out, we’ve got 5-10 years to get it right.”

With that in mind, Silverback Films, where Scholey is a director, has teamed up with WWF to create the Our Planet series for Netflix. Due out in 2019, the show will reveal “the huge riches left in the natural world” and there will be information available alongside it on where the problems are and how we can solve them.

Virtual reality could also engage people by helping them visualise what the natural world looks like, how it will change and the no-brainer solutions that can save it, Scholey explained, citing Pokémon’s use of augmented reality, GPS and gaming.

Past 2050, he believes, the situation will improve, with industry creating less carbon dioxide and world population decreasing. “If we find the solutions and get everything [all species] through the bottleneck, we can turn the clock back and get something as good as now or even the ‘50s or ‘60s,” the film-maker said. “And that is something worth striving for.”

Zebra stripes are in for horses, black is a definite nay

The 2016 Ig Nobel prize for physics has gone to Susanne Åkesson of Lund University in Sweden and her colleagues for discovering why blood-sucking horseflies plague dark-coloured horses more than their white neigh-bours. The win means animal physics researchers have swept up this prestigious prize, awarded last week for research that makes people laugh then think, for two years in a row.

“We have found that you’d rather be a white horse than a black one if you like to avoid being bitten by horseflies,” said Åkesson at the awards ceremony at Harvard University, US, “but you can also dress either in stripes like a zebra, or like myself, in a dotted coat.” The webcast of the ceremony indicates that Åkesson remained unplagued by horseflies throughout.

The flies, which are also known as tabanids, detect horizontally polarized light to find their victims. And white coats, unlike the bodies of black or brown horses, reflect depolarised light that flies find hard to spot.

The prize-winning research was kick-started when biologist Åkesson invited physicist Gábor Horváth from Eötvös University in Hungary to join her for an expedition to the North Pole. There they investigated how birds might use the sky’s polarisation pattern to navigate. And they got talking about other types of biology. “We started to discuss … how animals, in particular water-seeking insects, may be attracted to hosts or may be fooled by artificially reflecting surfaces,” Åkesson told me in an email. “The tabanid flies are seeking both water and hosts from which they may extract blood for egg-laying, and they have developed the capacity to see polarized light. This cue is central for them.”

Like dark horse coats, water surfaces reflect horizontally polarised light – light made up of waves that vibrate in just one plane. Once a female horsefly has got a horse in her sights and fed on its blood she’s able to produce more eggs, which she lays near water so that her larvae fall into the liquid when they hatch.

Stripes or spots are even better than a white coat at preventing horsefly attack, the team discovered, probably because they “not only break [up] the…black surface reflecting linearly polarized light, but also introduce a camouflage pattern,” Åkesson says. “A white object will show a large contrast with the surroundings, which may be used to detect it.”

Horseflies aren’t just a nagging – and painful – annoyance, they also transmit diseases. So you can now buy a zebra-striped coat for your pet horse to wear whilst it’s out to graze. Stripes are definitely in this season. For horses, at least.

Flying in the face of fashion

Black, that perennial fashion favourite, has proved a problem for dragonflies as well as ponies. Horváth and his team also received the 2016 physics Ig Nobel for finding that certain dragonflies are drawn to shiny black tombstones. Like horseflies, these insects look for the horizontally polarized light reflected from water so they can lay their eggs nearby. But shiny black tombstones reflect horizontally polarised light too, making them so attractive to some Sympetrum dragonflies that they lay eggs there instead. This makes the tombstones an “ecological trap” for the insects because these graveyard eggs can’t succeed – they don’t have access to the water they need.

Horváth holds a Hungarian patent for an actual insect trap based on polarisation. The horsefly problem could be solved by a trick of the light.

So last season

In 2015, the physics Ig Nobel went to Patricia Yang, David Hu, Jonathan Pham and Jerome Choo for discovering that all mammals weighing more than 3 kg take 21 seconds (plus or minus 13 seconds) to empty their bladders. A larger animal has a bigger bladder that contains more liquid when it’s full. For an elephant, the figure is a colossal 18 litres. You might think it would take longer to get rid of that urine. But a bigger animal also has a longer urethra (the tube to its bladder), which means the pressure on the liquid in that pipe will be higher and it will flow out faster. Hu’s research into the energy it takes a dog to shake itself dry and how mosquitoes avoid death by raindrop collision both feature in Furry Logic: the Physics of Animal Life.

Sadly, in 2014, the Ig Nobel slipped through the paws of animal physics when Kiyoshi Mabuchi, Kensei Tanaka, Daichi Uchijima and Rina Sakai, won the physics prize for measuring the friction when a person steps on a banana skin.

A busy week for Furry Logic

It’s been all go on the Furry Logic book front this week.img_4812

On Sunday morning the new Furry Logic webpage went live, thanks to Katja Durrani – check it out for an extract where you can find out about gender-swapping snakes and soggy dogs.

Last Wednesday I got home to this fine postcard from Jim Martin and Anna MacDiarmid at Bloomsbury, editors of the Sigma Science list, saying our book was finished and had gone to press.

On Saturday the book itself appeared at the local post office depot. It’s great to be able to hold the hardback after nearly two years’ work. Co-author Matin Durrani and I did just that simultaneously at Physics World Towers on Monday, where Hamish Johnston snapped our picture for the Physics World Facebook page.

 

The tale of Furry Logic

One day in the office I and my science journalist colleague Matin Durrani were chatting about a popular science book. We hadn’t enjoyed it. We reckoned we could do better. So we decided to put our money – or at least our words – where our mouths were. And the tale of Furry Logic: The Physics of Animal Life began.

As the name suggest, Furry Logic is about animals. And physics. The link doesn’t seem obvious but animals, including people, use physics every day, whether they’re aware of it or not. That bee buzzing round a flower is exploiting fluid dynamics to stay in the air. Pondskaters “know” enough about surface tension to perform miracles and walk on water. And when you run your body “calculates” how much force you need to push off the ground and speed yourself along.

In November 2012, PhysicsWorld magazine, which Matin edits, did a special issue on Animal Physics (hat-tip to PhysicsWorld features editor Louise Mayor for the idea). Stars included dogs that use simple harmonic motion to shake water from their fur and dodge hypothermia, mosquitoes that use Newton’s laws of motion to defy death by raindrop, and the hornet that has a built-in solar cell. These originals made it into Furry Logic, along with loggerhead turtles that loop round the Atlantic with the aid of their own magnetic compass, Miguel the tweeting electric eel, elephants that sense danger through their feet, and more.

There is no such thing as a “Department of Animal Physics” so the researchers working in this area are scattered far and wide – in departments of biology, of engineering, of physics… After nearly two years tracking these scientists down and crafting their fascinating discoveries, and the lives of the animals they study, into stories, our work is done. The illustrations and cover design are ready and we’re all set to check the proofs. Then it’s next stop, publication – on October 6th in the UK and January 31st 2017 in the US.

That chat in 2013 led not to a coffee break, a match analysis or a pub trip, but a book. A chance for us both to turn over, or at least create, a new leaf. We hope you enjoy it.