Philippa Kaur

CT scans of humans, chimpanzees and macaques reveal that human collarbones slow their growth rate in the final months of pregnancy, perhaps to make it easier for babies to squeeze through the pelvis

Humans

11 April 2022

By Christa Lesté-Lasserre
Collarbones may grow more slowly in the run-up to birthMartins Rudzitis/Getty Images
The collarbones of a human fetus grow more slowly just before birth, with growth then speeding up again during early childhood – probably an evolutionary compromise that allows humans’ relatively wide shoulders to fit through the pelvis.
Broad shoulders may help us with our balance and our ability to throw, and might even help us breathe more effectively. But a fetus with broad shoulders poses a problem during childbirth, because our upright posture has led humans to develop a relatively narrow pelvis.
The newly discovered slow-down-then-catch-up-later growth pattern in human clavicles – collarbones – around the time of birth appears to resolve this “shoulder mystery”, says Naoki Morimoto at Kyoto University in Japan.Advertisement
“There are two things that make human childbirth difficult: a big head and wide shoulders,” he says. “Since [difficult birth] is dangerous… it is sensible to think that humans evolved some ways to ease the problem.”
Previous studies have shown that the heads of human fetuses grow at fast rates in the uterus and then slow down just before birth, he says, which is a trend seen in other primates too – although human heads start to slow down their growth very late compared with other primates.

Curious to know whether the shoulders grow in a similar way, Morimoto and his colleagues examined CT scans of 81 humans (Homo sapiens), 64 chimpanzees (Pan troglodytes) and 31 Japanese macaques (Macaca fuscata). About half of these subjects were fetuses at various stages of development starting from about the beginning of the second trimester. The others were infants and adults.
The team measured the lengths of various bones in the skull, shoulders, upper arm, pelvis, thigh and vertebral column. Generally speaking, the vertebral column’s growth isn’t affected by birth constraints, so it serves as a good basis of comparison for the growth rates of the other bones, says Morimoto.
The researchers confirmed that the growth rate of the skull in all three species reduced just before birth, says Morimoto. Other bones, such as the arms and pelvis, had steady growth in the uterus, but then picked up speed after birth.
As for the collarbones, chimpanzees showed a fairly steady growth rate from before to after birth, he says. The macaques’ collarbones grew steadily before birth and then more slowly after birth.
The human collarbones, however, showed a standout growth pattern, he says. They slowed down about two months before birth and then sped up again over the next five years – creating what the researchers call a “growth depression” that lines up perfectly with when the shoulders need to fit through the pelvis.
“Currently, we simply do not know why this specific pattern in the shoulder – and not other ways like [a slower, steadier growth] – was selected in humans as a means to ease the difficult childbirth,” says co-author Mikaze Kawada, also at Kyoto University. “We need to wait for further studies.”
Journal reference: PNAS, DOI: 10.1073/pnas.2114935119
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The Antikythera mechanism, often called the world’s first computer could calculate the timing of cosmic events – and now we may know the date it was calibrated to

Space

7 April 2022

By Leah Crane
A functional model of the Antikythera mechanismA. Voulgaris
We may have figured out the date from which an ancient device often described as the first computer began its calculations. This device, called the Antikythera mechanism, was built sometime between the years 200 BC and 60 BC, and it was used to track time and predict the motions of celestial bodies.
A spiral shape inset in the back of the mechanism depicts a 223-month cycle called a Saros, which is based on the amount of time it takes for the sun, moon and … More

A tsunami 3800 years ago devastated the coastline of Chile and encouraged hunter-gatherers to move inland, where they stayed for the next 1000 years

Humans

6 April 2022

By Michael Marshall
The Atacama desert in ChileShutterstock/tjalex
An earthquake as large as any in recorded history struck the coast of Chile about 3800 years ago, triggering a tsunami that caused devastation along 1000 kilometres of coastline. In the wake of the tsunami, local hunter-gatherers began spending less time near the coast and moved cemeteries further inland, staying there for 1000 years or more, despite not having a system of writing to convey information about the disaster. 
It is a remarkable example of a society transforming itself to handle natural threats, say the researchers who studied the event.
The team, led by Gabriel Easton at the University of Chile in Santiago, spent years in the Atacama desert on the west coast of South America, gathering evidence of an ancient tsunami.Advertisement
At multiple sites, they found a layer of distinctive sediment dumped by a tsunami. Radiocarbon dates from charcoal and shells in archaeological deposits directly overlying the tsunami sediment suggest it happened about 3800 years ago.
It is impressive that the team has found evidence over such a wide area, says Eugenia Gayo, director of Millennium Nucleus Upwell in Concepción, Chile. “It’s robust.”

The coast of Chile lies on a subduction zone, where one of the tectonic plates that make up Earth’s surface is being forced under another. As a result, the region is prone to large earthquakes. However, the written record in this region is quite short, so it is unclear how big the quakes can be and how often the biggest ones occur.
“We propose that this earthquake was similar to the Valdivia earthquake that occurred in 1960 in southern Chile,” says Easton. “This is the largest earthquake ever recorded in history.” The Valdivia quake had a magnitude of about 9.5, and Easton’s team says the tremor 3800 years ago was similar.
In theory, the Valdivia quake could have been a one-off caused by a very rare combination of circumstances, says Easton. But if a similar quake happened within the past 5000 years, that can’t be true. “This is our proposal, that this area in northern Chile is capable to produce earthquakes of this size,” he says.
Other subduction zones may also have been underestimated, says Easton. He points to the 2011 Tōhoku earthquake, which caused devastation in Japan. Many seismologists thought the region could only produce earthquakes of about magnitude 8.3, but the Tōhoku quake was 9.0 or 9.1.

People have lived in the Atacama for more than 12,000 years. Although the desert gets little rainfall, the marine ecosystems along the coast are rich so hunter-gatherer societies have thrived.
However, Easton and his team documented major shifts that occurred around 3800 years ago. Archaeological sites near the coast show less evidence of habitation, suggesting people stopped going there or at least spent less time there.
Furthermore, cemeteries were moved inland and uphill. The local people mummified their relatives’ bodies and placed great value on having their dead ancestors nearby – a practice that continues to this day in communities in the Andes. “The most important thing that the families and the communities had at that time were their parents,” says Easton, and they took great care to protect them.
This new pattern of behaviour lasted a long time, with many sites only being reoccupied between 1500 and 1000 years ago. “This is kind of surprising, because people usually have a short memory for this kind of event,” says Gayo. Even maintaining the behaviour for 1000 years would have meant sustaining it for 40 generations. “That is a lot.”
It isn’t clear how the memory was preserved. Easton says the message may have been passed on orally, and perhaps through pictures on stone.
For Gayo, the lesson is that sometimes it is necessary to make big changes to adapt to natural hazards. That includes modern societies, which are threatened by growing climate extremes and rising seas. “You need to transform radically,” she says.
Journal reference: Science Advances, DOI: 10.1126/sciadv.abm2996
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An intriguing new book by a semi-professional poker player looks at why we feel lucky, and reflects on some hard-won lessons about living with uncertainty

Humans

6 April 2022

By Simon Ings

RUSSIAN novelist Fyodor Dostoevsky was a gambling addict. He believed that if he could only maintain his composure, the various strategies and systems he dreamed up to beat the roulette wheel would one day pay off. He was kidding himself. No strategy can defeat pure chance.
David Flusfeder is a semi-professional poker player, who knows all about the thrill of the gamble. In Luck, he bypasses the scientific harsh truth about randomness and probability and instead has written a book about the human side of luck, which he defines as “the operations of chance taken personally”.
His eccentric, insightful meditations focus on fortune’s favourites and its gulls throughout history. We hear the stories of the Marquis de Dangeau, 18th-century Versailles’s wiliest card shark, right up to the experience of four-time lottery winner Joan Ginther, also known as”the luckiest woman on Earth”.
In an effort to stop his project sprawling, each of the essays here is largely self-contained. They have to be, because Flusfeder decided to put the hand of fate to good use by presenting them in an order determined by an online randomiser.
Dostoevsky’s experience is perhaps the most compelling. Even after he managed to rid himself of his addiction, the novelist retained the conviction “that in games of chance, if one has perfect control of one’s will, so that the subtlety of one’s intelligence and one’s power of calculation are preserved, one cannot fail to overcome the brutality of blind chance and to win.”
Flusfeder reckons Dostoevsky was born in the wrong place at the right time; he should have been playing poker with French settlers in New Orleans. The card game invented there in 1829 really does reward composure and nerve, as well as luck.
Not that poker is an altogether rational pursuit. If it were, then Flusfeder wouldn’t be wearing green underpants to every important game. Superstition abounds on the poker circuit, as it does wherever people wield little or no control over their lives. Professional tennis is one example, writes Flusfeder. “There is so much time to think, and doubt, and lose the learned rhythms of technique, and to be afraid”, that the sport is awash with lucky tics, habits and absurd pre-match routines, he points out.
Superstition, Flusfeder argues, isn’t some primitive hangover from our distant past. It is the inevitable result of our capacity for taking mental shortcuts, which makes us capable of thinking on our feet, and without which we wouldn’t be able to function at all. If we had to constantly re-evaluate what was going on around us, we would quickly get left behind.
Instead, our brains make reasonable assumptions and update them if necessary. Along the way, we develop habits, and the impression that we live in a deterministic world in which what happened yesterday is a reliable guide for our actions today.
This works well enough in day-to-day life, but, writes Flusfeder, the extension of this very human way of thinking to economics often fails when it turns out that past results are an imperfect guide to future performance.
On this, statistician David Spiegelhalter, who studies the public perception of risk, puts it bluntly. Probability doesn’t exist outside the mind, he says: “It is not an objective aspect of the world. It’s a way to operationalise a belief.” At best, he says, it provides us with a map to help us navigate outcomes that are immeasurable and ultimately unknowable.
Given our weaknesses in the face of randomness, how should we proceed? According to Flusfeder, rather than cowering from the unknown and avoiding all randomness, we should pick our battles carefully, seizing good fortune when it arises, while swerving unnecessary risks. It is an imperfect guide to life, but it is a start at least.
Virtue may be an even better option, says Flusfeder. A life lived with honesty and integrity will at least be consistent, whether we are suffering adversity or enjoying good fortune. As the Renaissance poet Petrarch put it: “Many times whom fortune has made bond, virtue has made free.”

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Feedback is our weekly column of bizarre stories, implausible advertising claims, confusing instructions and more

Humans

6 April 2022

Josie Ford
Quantum ‘do
Feedback was relieved to read elsewhere in this august rag recently that black holes aren’t bald, featureless entities with an ever-expanding waistline, but have a bubbling frizziness around their outskirts known in some quarters as “quantum hair” (26 March, p 10). We are relieved not just because the middle-aged look has never been fashionable, but also because this promises a resolution to Stephen Hawking’s black hole information paradox, an unsolvable conundrum in fundamental physics that is also getting depressingly middle-aged.
And developing that new, fresh look is as simple as popping a daily pill, as Suzie Shrubb points out. She forwards us – with an eye on the black holes, we hope, not us – details of Quantum Nutrition Labs’ Quantum Hair, Skin, Nails capsules. These promise “Bioavailable Solubilized Keratin for Quantum-State Support for The Skin, Hair and Nails”, something we find merits the capitals, even as we wonder with Suzie whether the quantum state bit expresses some uncertainty about the product’s efficacy. Still, as she reasonably points out, you will only ever know after you have looked in the box.
For timeless style right from big bang to heat death, we can also recommend Zotos’s Quantum Classic Body hair perm, an acid perm that “creates soft, supportive body and supportive waves for a ‘non-permed’ look”. Coming soon to an event horizon near you.Advertisement
Lose friends, stay healthy
Epidemiology news, as Korean Vaccine Society vice president Ma Sang-hyuk announces that if you haven’t had the dreaded lurgy yet, it is because you have no friends. “Adults who have not yet been infected with COVID-19 are those who have interpersonal problems,” he is reported to have written on Facebook – comments that seem to have won him few friends, and so perhaps a degree of protection, as they were subsequently hastily deleted.
Feedback’s experience suggests you hardly need be in contact with anyone to catch the latest variant nasty. Certainly, we have been trying to build up immunity to infection through social isolation for years, and it didn’t work for us.
Not a prayer
Also strangely transient is Eternal Prayer, a website that briefly offered to mint the prayers of the devout as non-fungible tokens for a small consideration of real-world money.
As deities move in mysterious ways, it seems not unreasonable to us to desire non-falsifiable records of contracts entered into, even if, dinosaur that we are, we prefer the tablets of stone thing. But with the site now defunct, our eternal, fruitless search for meaning in the blockchain continues.
A mattress for all seasons
Bringing us back down to earth, Richard Bartlett notes that the care instructions for his John Lewis mattress include the advice “No turning required, rotate with the seasons.” “Perhaps I should not move it at all relative to the bed but simply allow the mattress to orbit the sun?” he asks. We consider this a wise starting point for anyone invested in a good night’s sleep. Or you could try the alternative interpretation of rotating yourself with the seasons, and see where that lands you.
Come shapely bombs
Feedback is a fan of what novelist Anthony Burgess termed the “arresting opening“. A frisson passes through us as we peruse an article from The Washington Post sent in by Mike Shefler of Gibsonia, Pennsylvania, among others. “Near steep vineyards of riesling grapes, in an underground vault at an air force base in western Germany, sits an American nuclear bomb. More than one of them, actually,” we read. “Each bomb is about the length of two refrigerators laid down end to end and as heavy as the average adult male musk ox. The bombs are slender and pointy and a little more than a foot wide.” We join Mike in a waking reverie on the slender pointiness of the adult male musk ox, and feel the mind-expanding power of quality journalism.
Naughty corner
“I know it’s a bad habit”, sighs our man with the laser sight Jeff Hecht, bringing us to our senses again as he forwards us a briefing from the Government Matters website on high-energy laser weapons. We read that the US Department of Defense plans to deploy a 300-kilowatt laser for testing this November and to develop megawatt lasers effective against some ballistic missiles within a few years. The progress is “really exciting”, says retired US Air Force colonel and director of the Mitchell Institute for Aerospace Studies, Mark Gunzinger.
From beyond the jrave
Stephen Wilhite, creator of the GIF, an invention that has done much to remove the need for words in internet communication, has died. We are commemorating him by playing our favourite GIF of UK politician Liz Truss pronouncing the words “pork markets” with relish. No reason, which is the point.
Sadly, there is no chance of reanimation for Wilhite, but his legacy has brought joy to millions, as well as a lovely debate about pronunciation. In lieu of words on accepting the 2013 Webby Award for lifetime achievement, Wilhite played a five-word animated gif: “IT’S PRONOUNCED “JIF” NOT “GIF”. Somehow, however often you repeat that one, it’s not sticking.
Got a story for Feedback?
You can send stories to Feedback by email at feedback@newscientist.com. Please include your home address. This week’s and past Feedbacks can be seen on our website. More

Shutterstock/Madlen
IT WAS out in the desert of New Mexico that humanity first tested the atomic bomb, creating an explosion that left an indelible imprint on our planet. In the same area, just a few dozen kilometres south, scientists are now finding imprints of quite a different sort: human footprints from the Stone Age. These tracks don’t have anything like the historical significance of the first nuclear test – and that is precisely why they are so important.
Archaeology often focuses on the big picture: technological shifts, epic migrations, the fall of civilisations. By contrast, the stones and bones we dig up … More

Chris Faulkes and Lorna Faulkes
Watch
The Naked Mole-rat: Animal Superhero by evolutionary ecologist Chris Faulkes will explain how this rodent altered our view of human health and ageing. This online talk by London’s Linnean Society is on 13 April at 12.30 BST.

Read
The Book of Minds by Philip Ball argues that we must look beyond our own brains and delve into the minds of other creatures if we want to truly understand ourselves and comprehend the possibility of alien or machine intelligence.Advertisement
Amazon Studios
Watch
Outer Range stars Josh Brolin as a rancher in the Wyoming wilderness whose grip on reality is called into question when a mysterious black void opens up in his western pasture. It will stream on Amazon Prime from 15 April.

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A portrait of three intrepid glaciologists brings the reality of climate change and glacial melting into sharp focus in this powerful documentary

Humans

6 April 2022

By Davide Abbatescianni
Leading glaciologist Alun Hubbard descends into a seemingly bottomless crevasseCourtesy of CPH:DOX 2022
Into the Ice
Lars Henrik Ostenfeld
CPH:DOX Film FestivalAdvertisement

A MAJESTIC aerial shot of the Arctic landscape opens Lars Henrik Ostenfeld’s epic documentary Into the Ice. Then his narration hits us with the hard truth: “The Greenland inland ice harbours a secret. You can see our future in it.” As if to illustrate what that future might look like, the camera then pans to deep rivers of meltwater.
The message of Ostenfeld’s film is familiar, yet what sets it apart is its focus on the fieldwork of three of the world’s leading glaciologists: Alun Hubbard, Dorthe Dahl-Jensen and Jason Box. Ostenfeld travels with them, on three separate trips, to the Arctic as they monitor how fast the Greenland ice sheet is melting.
Ostenfeld provides intimate portraits of the researchers, highlighting their distinct personalities and the motivations behind their work. Box is a family man who, when he isn’t playing with his daughter, is happiest digging the snow while listening to ABBA’s hit Chiquitita. Hubbard, the most adventurous of the three, embraces the idea of living every day as “a complete surprise”. His perilous descent into the depths of a seemingly bottomless crevasse is a case in point.
Dahl-Jensen, as Box describes her, is “about science with a capital S” and is dedicated to drilling ice cores as a window into the past. “When you walk through ice, you walk on climate history,” she says. She points to a darker ice layer, which dates from the last glacial period, while a more distant, lighter part is from an interglacial period.
During his time with the researchers, Ostenfeld becomes fully immersed in their work and their mission. His presence is well balanced and respectful, and his feelings of concern, fear and admiration emerge beautifully through his intimate voice-over commentary.
In this way, Ostenfeld achieves his aim of creating a strong empathic bond with the audience. This allows him to deliver a more serious message about the importance of studying changes in the ice as they are happening, no matter how perilous an undertaking it may be.
Throughout, we learn how the study of ice and its history are essential to uncovering the scope and consequences of climate change, and the importance of collecting and analysing data that will help us update our predictions of global sea level rise.
The initial light-hearted tone and good humour of the scientists gradually give way to a more serious feel as the realities of life and work in the Arctic become clear. We see the scientists face a lashing storm that forces them to hide in their tents for two days. And we feel their fear and excitement as they take on the elements to gather data.
The dangers of fieldwork become only too apparent as Box learns of the death of his mentor, climate scientist Konrad Steffen, who fell into an ice crevasse elsewhere in Greenland, on a separate research trip.
Towards the end of the film, Box and Hubbard head back into the deep crevasse to resume their work, only to discover an uncomfortable truth: the meltwater under the ice has progressed to a level never seen before. The glaciers are melting at a faster pace than we thought and our predictions of sea level rise are probably too cautious.
Accompanied by striking imagery and an engaging instrumental score, Into the Ice is a powerful documentary and one of the unmissable titles of this year’s festival season. It doesn’t try to soften the blow or to end on a hopeful note. Instead, it is a touching wake-up call, rich in sincerity and brutal home truths.

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