Humans

From frankincense to cacao and vanilla, Scent: A natural history of fragrance shows how aromatic substances have helped shape human culture

Humans

17 August 2022

By Chris Stokel-Walker
Fragrances from plants such as roses help make established and new perfumesOliver Rossi/Getty Images
Scent: A natural history of fragrance
Elise Vernon Pearlstine
Yale University Press
FOR countless people worldwide, their first inkling that they had covid-19 didn’t come from a test, but from something far more visceral: anosmia, the loss of the ability to smell.
Our sense of smell, and our understanding of it, helps us to navigate the world, protecting us from harm and adding to the joy of living in equal measures. Catching a whiff of mercaptan, the eggy-smelling chemical … More

Kostiantyn Filichkin/Getty Images
Visit
The Science of Psychedelics, and how to apply them to mental health conditions, is a focus for neuroscientist Maria Balaet. Hear her talk at the Lord Ashcroft Building, University of Cambridge, at 7pm BST on 22 August.
Watch
See, a dystopian fantasy set in a future where people have lost their sense of sight, returns for its third and final season. Created by screenwriter Steven Knight and starring Jason Momoa, you can catch it on Apple TV+ from 26 August.
Apple TV
Read
Tomorrow’s Parties, edited by Jonathan Strahan, shows us life in the Anthropocene as climate change bites deeper. … More

By cleverly capturing the behaviour of our feline friends, Stray offers a great experience for those who fancy spending time as a cat, says Jacob Aron

Humans

17 August 2022

By Jacob Aron
One of Dead City’s humanoid robots – from the perspective of a catBlueTwelve Studio
Stray
BlueTwelve Studio
PC, PlayStation 4 and 5
MY VIDEO game-playing career is littered with incarnations of the post-apocalypse, a setting that is such a cliché that I have probably explored the ruined wastelands of most US states in various guises. But I have never done it as a cat.
On the face of it, Stray‘s premise – you are a cat trying to escape from an underground city populated by robots – sounds like a … More

Expand your plant collection for free by saving seeds this year, storing them over the winter and sowing them next spring, says Clare Wilson

Humans

17 August 2022

By Clare Wilson
GAP Photos/Chris Burrows
GROWING your own plants using seeds saved from the previous year has several benefits. It is free, easy and you already know if these plant varieties grow well in your garden.
You can also branch out, if you have been coveting any of your neighbours’ flowers, by asking them if they could donate a few flower heads once they have set seed. I have acquired some tall ornamental grasses by taking a few seeds from some striking specimens at my local park.
Bear in mind that some hybrid “F1” varieties of fruits and vegetables shouldn’t have their seeds stored. These … More

Waste water contains a treasure trove of data on our health, well-being and inequality, and can be used to head off epidemics, track pandemics and even spot new designer drugs before their effects show up in the population. But how much information are we willing to flush down the toilet?

Humans

16 August 2022

By Claire Ainsworth
The countless chemicals and pathogens that you flush away end up in your nearest sewage treatment plantAbstract Aerial Art/Getty Images
WHAT’S the largest source of mass moving in and out of a city every day? You think, if it’s a port city, it must be boats – or, you know, maybe if it’s a landlocked city, it’s trains or trucks or cars or planes. No, it’s water. It’s water. There’s so much more water moving in and out of a city any day than there is any kind of cargo. It’s basically pure water coming in. And then the water that leaves has some traces of almost every human activity that’s going on in the city.”
Once Eric Alm is in full flow, it is hard to stop him. But it isn’t hard to understand his enthusiasm. Alm, a biological engineer at the Massachusetts Institute of Technology, is one of a growing band of researchers turning their attention to the fluid coursing through our sewers. This waste water, as it is known, contains the whispered biochemical confessions of millions of people, and by listening to them, scientists can paint surprisingly detailed pictures of our health, wealth and environment, head off epidemics, track pandemics and even spot new “designer” drugs before their effects show up in the population.
Water treatment plantSuriyapong Thongsawang/Getty Images
The field, called waste water-based epidemiology, not only has the potential to revolutionise public health but also transform our view of sewage from disgusting waste to … More

Unlike people, 43 species of monkeys and apes are known to have so-called vocal membranes, which may prevent them from having precise voice control

Humans

11 August 2022

By Clare Wilson
Unlike in other primates, the human voice box has lost small tissue structures called vocal membranes, which may have been involved in the evolution of speechSEBASTIAN KAULITZKI/SCIENCE PHOTO LIBRARY
The loss of small tissue structures from the voice box may have been essential for the evolution of human speech.
In a study of 43 non-human primates, all the animals had “vocal membranes”, a small extension of the throat’s vocal cords that makes their sounds louder and higher but also more irregular and harder to control.
As humans lack vocal membranes, this suggests they were lost when our ancestors diverged from chimpanzees to allow more precise voice control, says Tecumseh Fitch at the University of Vienna in Austria.Advertisement
While many animals make calls to communicate, the evolution of complex human speech seems to have required anatomical changes, as well as changes in the brain. In humans, the vocal cords are flaps of tissue in the throat that vibrate as air is expelled from the lungs, allowing us to make “voiced” sounds, as opposed to breathy ones.
We already knew that a few species of monkeys and apes have vocal membranes. To better understand the loss of these structures in humans, Fitch’s team looked at the voice box, also known as the larynx, of 43 species of apes and monkeys. This was done by carrying out magnetic resonance imaging (MRI) or computed tomography (CT) scans on dead or anaesthetised animals in the first such large-scale study of primates. The researchers found that all 43 species had this vocal cord extension.
The team also analysed video footage that showed the voice box of an anaesthetised chimpanzee with an endoscope in its throat while the animal made grunts and growls as it was waking up. They did the same for anaesthetised rhesus macaques and squirrel monkeys that were stimulated to make noises by having an electrode put into the part of their brain that causes them to produce vocalisations.

The researchers found that in all these animals, vibration and collision of the vocal membranes are the primary source of their calls, as their vocal cords were in motion less often.
If humans still had vocal membranes, our speech would probably sound more rough and variable, with abrupt pitch changes, like someone with laryngitis, says Fitch.
“A key thing that distinguishes human speech from animal sounds is our fine-grained control over the sounds we make. That is only possible if our vocal apparatus is easy for our brains to control,” says Richard Futrell at the University of California, Irvine. “If the system is complex, then it will behave in a way that is chaotic and unpredictable.”
But Adriano Lameira at the University of Warwick in the UK says many apes and monkeys make both loud and irregular calls as well as some quieter and more controlled noises. “The alleged limiting effect [of vocal membranes] on primate vocal production seems exaggerated,” he says.
Journal reference: Science, DOI: 10.1126/science.abm1574

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Based on the book by journalist Sheri Fink, this TV mini-series dramatises the shocking stories of health workers and patients whose lives are changed forever as Hurricane Katrina overwhelms a US hospital in 2005, finds Bethan Ackerley

Humans

10 August 2022

By Bethan Ackerley
Anna Pou (Vera Farmiga), front, and Karen Wynn (Adepero Oduye)Courtesy of Apple
Five Days at Memorial
Apple TV+
ON 11 September 2005, 45 bodies were recovered from Memorial Medical Center, New Orleans. The hospital had been hit by Hurricane Katrina, then the most devastating storm in US history. Patients, staff and their families were stranded for five days by floodwaters. Conditions were apocalyptic. Deaths were expected.
The aftermath brought uncomfortable revelations. Some bodies contained potentially dangerous levels of morphine and other drugs. The actions of Anna Pou, a doctor at the hospital, were … More

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

Humans

10 August 2022

Josie Ford
Hair-raising heirloom
Tidying the stationery cupboard throws up many archaeological treasures, but nothing so exciting, or terrifying, as the discovery made by a gentleman sorting through his deceased brother’s attic in Kent the other day. He found a head.
This Egyptian mummy’s remains, brought to England as a souvenir, must have been passed down the family line for several generations. You would think it might have come up in conversation now and again. But no: the discoverer, who has gifted the grisly object to Canterbury Museums and Galleries, says he knew nothing about it. A CT scan has established that … More