Humans

By Sam Wong
Valeri Vatel/Alamy
PIZZA is the ultimate fast food, and the speed of cooking is vital to achieving perfection: brown and crispy on the bottom, but still tender and chewy on the inside, with a light, airy crust. This is easy to attain in a traditional pizza oven, which can reach temperatures of around 500°C and cook a pizza in under 2 minutes. At home, it is more challenging, but there are some tricks to making satisfying pizzas.
Paradoxically, it helps to think of pizza as slow food and start the process a few days early – difficult, I know, … More

Social media is awash with people claiming that regular cold dips have transformed their health and well-being. We investigate whether it is actually good for you

Health 10 March 2021
By Alison George
Plunging the body into cold water stimulates the release of a cocktail of invigorating chemicals
Jacob Staedler/EyeEm/Getty Images
“IT’S like pressing Control-Alt-Delete on a computer,” says Cath Pendleton. “When I’m in the water, I’m so focused on my body, my brain switches off. It’s just me and the swim.”
Pendleton, an ice swimmer based in Merthyr Tydfil, UK, is hardier than most. In 2020, five years after discovering she didn’t mind swimming in very cold water, she became the first person to swim a mile inside the Antarctic circle. Part of her training involved sitting in a freezer in her shed.
She is far from alone in her enthusiasm for cold water, however. Thanks to media reports of the mental health benefits of a chilly dip and pool closures due to covid-19, soaring numbers are now taking to rivers, lakes and the sea – once the preserves of a handful of seriously tough year-round swimmers. An estimated 7.5 million people swim outdoors in the UK alone, with an increasing number swimming through the winter. Global figures are hard to come by, but the International Winter Swimming Association has seen a boom in registered winter swimmers around the world, even in China, Russia and Finland, where water temperatures can drop below 0°C.
But is there anything more to it than the joy of being in nature, combined with the perverse euphoria of defying the cold? According to the latest research, the answer is maybe. Recent studies have begun to turn up evidence that cold-water immersion may alleviate stress and depression and help tackle autoimmune disorders. It might even tap into a … More

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Gut Feelings: The microbiome and our health by Alessio Fasano and Susie Flaherty reveals how understanding this alien inner world will make it possible to target medicines to an individual’s needs at the molecular level.
Instant Film
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An Impossible Project, streaming on digital platforms from 15 March, celebrates the return of analogue formats, from Polaroid to vinyl. The film highlights the work of Viennese biologist Florian “Doc” Kaps to reverse the tide of technological “progress”.

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Double Blind by Edward St Aubyn leaps from London to Cap d’Antibes in southern France to a rewilded corner of Sussex, UK, in a thrilling and mischievous tale of ecology, psychoanalysis, genetics and neuroscience.
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By Michael Marshall
This may be the oldest stone tool yet found outside Africa
Dominique Cauche
ANCESTRAL humans may have left Africa half a million years earlier than generally thought, according to archaeologists who claim to have found a primitive stone tool from 2.6 million years ago in northern India.
If early humans really were there then, it would mean they migrated out of Africa remarkably early. The oldest evidence of the Homo lineage is from 2.8 million years ago at Ledi-Geraru in Ethiopia. This means these hominins would have had to expand their range rapidly to reach India.
The claim is … More

New Scientist Future of Science Survey in association with

New Scientist, in association with IPSEN, wants to find out. Take part in our survey and help us learn how to inspire more young minds into careers in science and healthcare.

Health 8 March 2021The innovation of tomorrow will be driven by the new generation of young minds.  But what do young people really think about science?  What do they like about science, what do they dislike, and what would put them off a career in science or healthcare?
Help us find out.
We want you to answer if you are aged 16-21. If you have children aged 7 to 15 please would you fill out the survey with them. We will be publishing the results in a forthcoming issue of New Scientist.
The questionnaire takes up to 10 minutes to complete. The information you give will only be used in aggregate and your views will be completely confidential in accordance with the UK Market Research Society’s Code of Conduct.
You can complete the survey here.
ALL-UK-001204 February 2021
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By Krista Charles
People in Finland in 1941
Roman Nerud/Alamy
The second world war left a major mark on the genetic composition of Finland, researchers have found, though the work may not have included minority ethnic groups.
Matti Pirinen at the University of Helsinki, Finland, and his colleagues looked at the genomes of around 18,500 people to study how the genetic composition of 10 populations across 12 geographic regions covering most of Finland changed between 1923 and 1987.

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“We can really see with an accuracy of one year how the genetic structure has changed in Finland during the last century,” says Pirinen.
The team found that urbanisation has caused some changes in the genetics of people in Finland. But the biggest impact, increasing the number of regions each individual could trace their ancestry to,  came after the forced movement of people from Finnish Karelia to the rest of the country in 1940, following a peace treaty with the Soviet Union during the second world war.

The researchers chose the genomes of 2741 individuals who were born and whose parents were born within the 12 regions to form the basis of the 10 populations they studied. This definition could skew the results, says Eran Elhaik at Lund University in Sweden.
“Identifying people who lived closely next to each other as the most homogeneous people raises the question of how these people became so homogeneous,” says Elhaik. “These are likely farmers who have married each other for a very long time. What makes them represent the ancestors of Finns better than any other people in Finland?”
The researchers say that their populations probably don’t cover all relevant sources of genetic ancestry, such as minority ethnic groups, because it is likely that only a small number of individuals from these groups were included in the study. Individual data was pseudonymised, meaning it isn’t possible to know for sure, say the researchers, and they note that the study shouldn’t be used to define who is Finnish, in a social, legal or cultural sense.
Elhaik says this uncertainty over minority ethnic groups limits what the study can tell us about the Finnish population as a whole. “Focusing on a small data set of 10 per cent of the population carves Finns’ image as genetically homogeneous people. What about the rest of the people who are of more mixed origins and are not well represented by the model? No population is an island,” he says. “This method is not applicable to mixed individuals, which represent a growing proportion of individuals in any society.”

Journal reference: PLoS Genetics, DOI: 10.1371/journal.pgen.1009347
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By Ibrahim Sawal
The bacteria that causes tuberculosis
Phanie/Alamy
Ancient DNA reveals that people of European ancestry have lost a gene linked to tuberculosis (TB) susceptibility over centuries.
TB is one of the world’s deadliest diseases and is caused by Mycobacterium tuberculosis bacteria. People with two copies of a genetic variant called P1104A are more likely to develop symptoms of TB after being infected with the bacteria.

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To trace the frequency of P1104A over time, Gaspard Kerner at the Pasteur Institute in France and his team analysed modern human DNA from around the world and compared it to more than 1000 samples of ancient DNA from Europeans from the past 10,000 years.
They found that the variant first appeared in ancient DNA in low numbers around 8500 years ago in Western Eurasia. Using simulations and demographic models to date the origins and movements of this variant, the team predicted it may have originated in the same region around 30,000 years ago, long before the existence of TB in Europe. “It may have appeared randomly, like when animals have mutations in their genome,” says Kerner.
It then spread across central Europe 5000 years ago, and reached its highest frequency 3000 years ago, with around 10 per cent of the population carrying P1104A.
Kerner says it was able to spread without affecting an individual’s susceptibility to TB during that time as many people would only have one copy of the variant.

The frequency of the variant drastically decreased 2000 years ago, around the time modern TB bacteria became common. This may be because it was under strong negative selection from TB, Kerner says, as increasing migration made people more likely to inherit two copies of the variant and therefore become more susceptible to TB.
“Individuals carrying this mutation may have died faster than other individuals,” he says. The spread of TB during this time may have been aided by human migrations increasing populations and bringing new bacteria and diseases to Europe.

In modern Europeans and Americans, the variant appears in low frequencies, but it is absent in African and Eastern Asians populations. Kerner says this is consistent with the findings P1104A emerged in Eurasia, and that other genes may be behind the prevalence of TB in Africa and Asia today.
“People still get sick from TB, both in Europe and elsewhere,” says Vegard Eldholm at the Norwegian Institute of Public Health. Around 10 per cent of those infected with the bacteria develop TB. “This might reflect a long history of co-evolution, and humans having adapted to contain the infection. But it takes time for evolution to purge the gene,” Eldholm says.
Journal reference: The American Journal of Human Genetics, 10.1016/j.ajhg.2021.02.009., DOI: 10.1016/j.ajhg.2021.02.009.
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By Simon Ings
The symbol of the QAnon far-right conspiracy theory
Pacific Press/Lightrocket via Getty Images
You Are Here
Whitney Phillips and Ryan M. Milner

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MIT Press
THIS is a book about pollution, not of the physical environment, but of our civic discourse. It concerns disinformation (false, misleading information deliberately spread), misinformation (false, misleading information inadvertently spread) and malinformation (information with a basis in reality spread specifically to cause harm).
Communications experts Whitney Phillips and Ryan Milner finished their book just before the election that replaced Donald Trump with Joe Biden. That election and the seditious activities that prompted Trump’s second impeachment have clarified many of the issues the authors were at pains to explore. You Are Here: A field guide for navigating polarized speech, conspiracy theories, and our polluted media landscape is an invaluable guide to our problems around news, truth and fact.
The authors’ US-centric – but globally applicable – account of “fake news” begins with the rise of the Ku Klux Klan. Its deliberately silly name, cartoonish robes and the routines that accompanied all its activities, from rallies to lynchings, prefigured the “only joking” subcultures of Pepe the Frog and the like that dominate social media.
Next, their examination of the 1980s Satanic panics reveals much about conspiracy theories. They also unpick QAnon, a far-right conspiracy theory alleging that a secret cabal of cannibalistic, Satan-worshipping paedophiles plotted against Trump. This pulls together their points in a way that is more troubling for being so closely argued.
Polluted information is, they say, a public health emergency. By treating the information sphere as a threatened ecology, the authors push past factionalism to reveal how, when we use media, “the everyday actions of everyone else feed into and are reinforced by the worst actions of the worst actors”.

This is their most striking takeaway: the media landscape that enabled QAnon isn’t a machine out of alignment, or out of control, or somehow infected, but “a system that damages so much because it works so well”.
It is founded on principles that seem only laudable. Top of the list is the idea that to counter harms, we must call attention to them: “in other words, that light disinfects”. This is fine as long as light is hard to generate. But what happens when that light – the confluence of competing information sets, depicting competing realities – becomes blinding?
Take Google. The authors characterise it as an advertising platform that makes more money the more people use it. The deeper down the rabbit holes our searches go, the more Google and others earn, incentivising promulgators of conspiracy theories to produce content, creating “alternative media echo-systems”. When facts run out, create more. Media algorithms don’t care: they are designed to serve up as much as possible of what Phillips and Milner call pollution.
The authors bemoan the way memes, rumours and conspiracy theories have swallowed political discourse. They teeter on the edge of a more important truth: that our moral discourse has been swallowed too. You Are Here comes dangerously close to saying that social media has made whining cowards of us all. So what is to be done? The authors’ call for “foundational, systematic, top-to-bottom change” is mere floundering. It has taken the environmental movement decades to work out mechanisms to address the climate emergency. Nothing in You Are Here suggests the media emergency will be less intractable.

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