Humans

The interior of the monument in Spain known as the Menga dolmenMiguel Ángel Blanco de la Rubia
Neolithic people seem to have understood sophisticated concepts in science, such as physics and geology, using this knowledge to construct a megalithic monument in southern Spain.
Called the Menga dolmen, it is among the earliest European megaliths, dating to between 3600 and 3800 BC. Its roofed enclosure was constructed from 32 large stones, some of which are the biggest used in such structures. The heaviest one weighs in excess of 130 tonnes, more than three times as much as the heaviest stone at Stonehenge in the UK, which was erected more than 1000 years later.
“[In the Neolithic Period], it must have been very powerful to experience this building made with these enormous stones,” says Leonardo García Sanjuán at the University of Seville in Spain. “It still stirs you. It still causes an impression even today.”Advertisement

García Sanjuán and his colleagues have now performed detailed geological and archaeological analyses of the stones to infer what knowledge Menga’s builders would have needed to construct the monument, which is in the city of Antequera.
Paradoxically, they found that the rocks are a type of relatively fragile sandstone. While this means a greater risk of breaking, the team discovered that this was compensated for by shaping the stones so they locked into a very stable overall structure.
Neolithic people would have needed some way to make the blocks fit very tightly together, says Garcia Sanjuán. “It’s like Tetris,” he says. “If you look at the precision involved and how well each stone locks with each other, you have to think that they had an idea of angles, however rudimentary.”
The researchers also found that the 130-tonne stone, which was placed horizontally on top to form part of the roof, had been shaped so that its surface rises in the centre and declines towards the edges. This distributes force in a similar way to an arch, improving the roof’s strength, says García Sanjuán. “To the best of our knowledge, this is the first time that the principle of the arch has been documented in human history.”
Menga – whose purpose is unknown – is also aligned to produce distinct patterns of light in the interior during the summer solstice and has stones that are protected from water damage by several layers of carefully beaten clay, which adds to evidence supporting the builders’ knowledge around architecture and engineering.
“They knew about geology and the properties of the rocks they were using,” says García Sanjuán. “When you put all this together – you know, engineering, physics, geology, geometry, astronomy – it is something we can call science.”

There are Neolithic structures in France that rival Menga in size, but how they were built is less well understood, says García Sanjuán. “As it stands today, Menga is unique in Iberia and in western Europe.”
“What’s surprising about this is the level of sophistication,” says Susan Greaney at the University of Exeter, UK. “The architectural understanding of how the weight distribution works, I’ve not seen that anywhere else before.” But she adds that this is perhaps less a demonstration of an understanding of science than of architecture and engineering.

Topics:archaeology More

The interior of the monument in Spain known as the Menga dolmenMiguel Ángel Blanco de la Rubia
Neolithic people seem to have understood sophisticated concepts in science, such as physics and geology, using this knowledge to construct a megalithic monument in southern Spain.
Called the Menga dolmen, it is among the earliest of such structures, dating to between 3600 and 3800 BC. Its roofed enclosure was constructed from 32 large stones, some of which are the biggest used in this sort of monument. The heaviest one weighs in excess of 130 tonnes, more than three times as much as the heaviest stone at Stonehenge in the UK, which was erected more than 1000 years later.
“[In the Neolithic Period], it must have been very powerful to experience this building made with these enormous stones,” says Leonardo García Sanjuán at the University of Seville in Spain. “It still stirs you. It still causes an impression even today.”Advertisement

García Sanjuán and his colleagues have now performed detailed geological and archaeological analyses of the stones to infer what knowledge Menga’s builders would have needed to construct the monument, which is in the city of Antequera.
Paradoxically, they found that the rocks are a type of relatively fragile sandstone. While this means a greater risk of breaking, the team discovered that this was compensated for by shaping the stones so they locked into a very stable overall structure.
Neolithic people would have needed some way to make the blocks fit very tightly together, says Garcia Sanjuán. “It’s like Tetris,” he says. “If you look at the precision involved and how well each stone locks with each other, you have to think that they had an idea of angles, however rudimentary.”
The researchers also found that the 130-tonne stone, which was placed horizontally on top to form part of the roof, had been shaped so that its surface rises in the centre and declines towards the edges. This distributes force in a similar way to an arch, improving the roof’s strength, says García Sanjuán. “To the best of our knowledge, this is the first time that the principle of the arch has been documented in human history.”
Menga – whose purpose is unknown – is also aligned to produce distinct patterns of light in the interior during the summer solstice and has stones that are protected from water damage by several layers of carefully beaten clay, which adds to evidence supporting the builders’ knowledge around architecture and engineering.
“They knew about geology and the properties of the rocks they were using,” says García Sanjuán. “When you put all this together – you know, engineering, physics, geology, geometry, astronomy – it is something we can call science.”

There are Neolithic structures in France that rival Menga in size, but how they were built is less well understood, says García Sanjuán. “As it stands today, Menga is unique in Iberia and in western Europe.”
“What’s surprising about this is the level of sophistication,” says Susan Greaney at the University of Exeter, UK. “The architectural understanding of how the weight distribution works, I’ve not seen that anywhere else before.” But she adds that this is perhaps less a demonstration of an understanding of science than of architecture and engineering.

Article amended on 27 August 2024The headline and second paragraph of this article have been changed to correctly refer to the monument that was constructed.Topics:archaeology More

Coca leaves have psychoactive and therapeutic propertiesFabiano Sodi/Alamy
The mummified brain tissue of two people found in a 17th-century crypt in Milan, Italy, contains traces of cocaine, revealing that the drug was being used in Europe 200 years earlier than previously recorded.
Coca leaves, from which cocaine is derived, have been chewed in the plant’s native South America for thousands of years, but the drug only took off in Europe in the 19th century, when it was chemically isolated from the plant.
Spanish conquerors learned of the psychoactive and therapeutic properties of coca leaves, but… More

The altar stone lies inside Stonehenge’s two big rings of stonesGavin Hellier/roberthrding/Getty Images
A study of the 6-tonne altar stone at the heart of Stonehenge has shown that it was almost certainly brought there from north-east Scotland, much further than any other stone in the megalithic structure.
“All of us were stunned. We couldn’t believe it,” says geologist Anthony Clarke at Curtin University in Perth, Australia.
How the altar stone was transported all the way from Scotland to the south of England isn’t known, but it is most likely to have been brought by sea, says Clarke. There is evidence that people at this time were making sea journeys, he says.Advertisement

Stonehenge is thought to have been built over about 1500 years, starting around 5100 years ago. It consists of an outer circle of large stones weighing around 25 tonnes each, known as sarsens, and an inner ring and altar made of smaller stones generally of around 3 tonnes, known as bluestones. The term bluestone just means any rock that isn’t a sarsen – the bluestones are made of various kinds of rock.
“The thing that’s unique about Stonehenge is the distance that stones have been transported,” says geologist Richard Bevins at Aberystwyth University, UK. Most stone circles are made from rocks found within a kilometre of the site, says Bevins.
The source of the sarsens, however, has been traced to the West Woods of Wiltshire, around 25 kilometres from the site. And Bevins’s team has shown that almost all the bluestones come from the Preseli hills in Wales, about 280 kilometres away. One idea is that they were part of an even older Welsh stone monument that was moved.
The altar stone at Stonehenge is different to the other bluestones. “By the end of 2021, we’d come to the conclusion that the altar stone didn’t match any of the geology that we knew in Wales,” says team member Nick Pearce, also at Aberystwyth University.
This 5-metre-long stone is embedded in the ground with only one surface showing and is partly covered by two other stones. It is thought to have been put in place about 4500 years ago.
Stonehenge’s altar stone (embedded in the ground under the other stones) came from north-east ScotlandNick Pearce, Aberystwyth University
Now, Clarke has taken sophisticated equipment usually used in the mining industry and analysed samples of the altar stone. It is a sandstone, which means it is made of eroded grains of rock that piled up at the bottom of an ancient ocean and eventually stuck together to form a new rock. The age of each grain varies depending on when the rock it eroded from first formed, so different sandstones have a distinctive mix of grains of different ages.
Clarke analysed individual crystals of the minerals zircon, apatite and rutile within samples of the stone. These minerals contain uranium, which very slowly decays to lead, allowing them to be dated from the ratio of uranium to lead. For instance, the zircon in the stone is between 500 million and 3 billion years old.
The pattern of ages shows with greater than 95 per cent certainty that the altar stone is Old Red Sandstone from the Orcadian basin in north-east Scotland, says team member Chris Kirkland at Curtin University. This basin was once a massive ancient water body called Lake Orcadie.

The nearest matching Old Red Sandstone to Stonehenge is 750 kilometres away in the vicinity of Inverness, and the furthest is in the Shetland Islands up to 1000 kilometres away – hence why the team thinks the altar stone was probably transported by sea.
Glaciers can carry boulders long distances, but the evidence is that during the last glacial period, the flow of ice in the Orcadian region was northwards rather than southwards, says Kirkland.
So why was the altar stone brought such a long distance? “That is the great unanswerable question,” says Clarke. “All we know is it’s a 6-tonne piece of rock that’s come from 750 kilometres away. That, by itself, tells us an awful lot about the Neolithic society and its connectivity.”
“What they’ve done is pretty rigorous,” says David Nash at the University of Brighton, UK, whose team identified the precise source of the sarsens in Wiltshire. “It’s a really sound piece of work.”

Pinning down the source of the altar stone more precisely will be difficult because the Orcadian basin extends over a vast area and is up to 8 kilometres deep, says Nash. “That’s a big, big job, because there’s an awful lot of Old Red Sandstone in northern Scotland.”
With the sarsens, by contrast, there were fewer potential sources, so locating the exact one was easier, he says.
Genetic studies have shown that the people who did most of the construction of Stonehenge were largely replaced by a new wave of migrants by about 4000 years ago. This could be because a plague pandemic wiped out a large proportion of Europe’s inhabitants around this time.

Topics:archaeology/Stonehenge More

The Altamura Man skeleton in Lamalunga caveCostantino Buzi
This is an extract from Our Human Story, our newsletter about the revolution in archaeology. Sign up to receive it in your inbox for free every month.
Have you heard of Altamura Man? Since it was new to me, I’m going to guess that you may be unfamiliar with it. Which is peculiar, because it’s an astonishing specimen.
To find Altamura Man you would need to travel to Puglia (also known as Apulia) in southern Italy: if you think of Italy as looking like a boot, Puglia is… More

Excavations at Mololo cave on the island of Waigeo, where ancient plant resin was foundTristan Russell (The Raja Ampat Archaeological Project)
A tiny chunk of plant resin shows humans were living on an island in eastern Indonesia at least 55,000 years ago – revealing the likely route that modern humans took when migrating to Australia.
We know that modern humans journeyed to Australia by heading south-east from mainland Asia, travelling through what is now Indonesia and many other islands of South-East Asia. The exact timing is contested, says Dylan Gaffney at the University of Oxford. Modern genetic evidence suggests humans arrived less than 50,000 years ago, but archaeological evidence points to an earlier arrival, “perhaps 65,000 or even 80,000 years ago”, he says.
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What is more, the exact route they took is also contested because the geography of the region at the time was different. Earth was in a cold glacial period, so more water was locked up in ice sheets and sea levels were lower, meaning some landmasses that are now islands were connected to continents. In the western part of this region, Borneo, Sumatra and Java were all part of mainland Asia – while in the eastern part, New Guinea was joined to Australia.
This means there were two possible routes humans could have taken to reach Australia. The northern route heads directly east from Borneo to Sulawesi and on to New Guinea, then south into Australia. The southern route goes via Java, passing through Bali and Timor to northern Australia.
Possible routes to AustraliaDylan Gaffney/The Raja Ampat Archaeological Project
To help find out how people made the journey, Gaffney and his colleagues excavated Mololo cave on the island of Waigeo, one of the Raja Ampat islands just west of New Guinea and along the northern route. In the sediments on the cave floor, the team found evidence of human occupation such as charcoal and a few stone flakes.
Crucially, Gaffney’s team found a piece of resin just 1.4 centimetres across. It has an angular shape, suggesting it was cut from a tree rather than pooling naturally. Radiocarbon dating indicates it is at least 55,000 years old.
The resin was probably used as fuel for fires, says Gaffney. “It is very flammable and is a good light source in caves.” But there are other possibilities, such as fragrance or adhesive. Whatever its use, it shows that humans were on Waigeo at least 55,000 years ago. “We are demonstrating that people used the northern route,” says Gaffney.
Modern tree resin can help make fire and ancient resin may have been used in the same wayDylan Gaffney/The Raja Ampat Archaeological Project
The finding adds to the evidence that people first reached Australia via the northern route, says Kasih Norman at Griffith University in Queensland, Australia. Geographical models always pointed to the northern route because the sea crossings are easier. “You have more water crossings between islands to do along the northern route, but the crossings themselves are shorter,” she says. Furthermore, “you can always see to the next island”.
However, most archaeological excavations focused on the southern route, says Norman. Only in recent years have researchers like Gaffney begun exploring the northern option.
One key discovery, published in July, is a 50,000-year-old cave painting of a pig found on Sulawesi, along the northern route. Likewise, a study published in May found that there was no evidence of humans on Timor before 44,000 years ago. Timor lies on the southern route, suggesting this pathway was only used later.

A final intriguing mystery in all this concerns the absence of the Denisovans – an extinct group of humans known to have lived on mainland Asia – from Australia’s fossil record. Many populations in South-East Asia carry Denisovan DNA: this includes people from Papua New Guinea, who have DNA from two distinct Denisovan groups. That hinted, but didn’t prove, that Denisovans lived on New Guinea. Yet there is no sign of Denisovans on Australia. “As far as we’re aware,” says Norman, “there’s never been anyone else [but Homo sapiens] here.”

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Michael Kirkham
I am an only child. Saying this sometimes feels like a confession – not least when people respond with a well-meaning “oh, you don’t seem like it!”. Now, as the mother of a preschooler, I see my daughter navigating the same assumptions. “Does she have older siblings?” one teacher asked recently. “She plays so well with the other kids!”
If it seems like I am bragging about my (or my daughter’s) behaviour, you will have to excuse me: I am, after all, an only child.
For over a century, we have been seen as odd, at best; antisocial, neurotic and narcissistic, at worst. “Being an only child is a disease in itself,” declared 19th-century child psychologist Granville Stanley Hall.

Whether there are actually any differences between the personalities and well-being of singleton children and those with siblings remains a contentious question – one given fresh impetus by the growing trend of one-and-done parenting.
Single-child families have become more common since the 1970s in high-income countries, including the US and UK, whether “by constraint or by choice”, says éva Beaujouan, a demographer at the University of Vienna, Austria. In Europe, nearly half of all households with children have just one child.
Despite their growing popularity, one-child families continue to encounter a long-held view that this arrangement is somehow harmful. Fortunately, delving into contemporary research can offer a degree of clarity – and it hints that being an only child can come with surprising outcomes. The findings may offer some reassurance for one-and-done parents and those still debating how many… More

The Xingu Indigenous Territory in the Amazon may contain over 900 square kilometres of dark earthLeo F Freitas/Getty Images
Rich soil in the Amazon cultivated over centuries by Indigenous communities may store billions of tonnes of carbon, suggesting that the rainforest plays an even larger role in stabilising the global climate than previously thought.
The soil, known as “terra preta” or “dark earth” for its distinctive colour, is formed by people spreading ash and other organic waste around settlements. It is more fertile than the region’s typically sandy, nutrient-poor soils, and stores around double the carbon. In some areas,… More