This post was originally published last year. I’m travelling for a few weeks, so I’m reloading some of my favourite stories from 2011. Normal service will resume when I get back.

Meet the world’s smallest farmer – a “social amoeba” that seeds new land with bacteria, which it then eats. Just as human farmers carry seeds and livestock when they move to new areas, the amoeba can prepare for harsh conditions by bringing a ready food supply with it. It joins ants, termites and humans on the list of creatures that practice agriculture.

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This post was originally published last year. I’m travelling for a few weeks, so I’m reloading some of my favourite stories from 2011. Normal service will resume when I get back.
Two people are dancing a waltz, and it is not going well. One is tall and the other short; one is graceful, the other flat-footed; and both are stepping to completely different rhythms. The result is chaos, and the dance falls apart. Their situation mirrors a problem faced by all complex life on Earth. Whether we’re animal or plant, fungus or alga, we all need two very different partners to dance in step with one another. A mismatch can be disastrous.

Virtually all complex cells – better known as eukaryotes – have at least two separate genomes. The main one sits in the central nucleus. There’s also a smaller one in tiny bean-shaped structures called mitochondria, little batteries that provide the cell with energy. Both sets of genes must work together. Neither functions properly without the other.

Mitochondria came from a free-living bacterium that was engulfed by a larger cell a few billion years ago. The two eventually became one. Their fateful partnership revolutionised life on this planet, giving it a surge of power that allowed it to become complex and big (see here for the full story). But the alliance between mitochondria and their host cells is a delicate one.

Both genomes evolve in very different ways. Mitochondrial genes are only passed down from mother to child, whereas the nuclear genome is a fusion of both mum’s and dad’s genes. This means that mitochondria genes evolve much faster than nuclear ones – around 10 to 30 times faster in animals and up to a hundred thousand times faster in some fungi. These dance partners are naturally drawn to different rhythms.

This is a big and underappreciated problem because the nuclear and mitochondrial genomes cannot afford to clash. In a new paper, Nick Lane, a biochemist at University College London, argues that some of the most fundamental aspects of eukaryotic life are driven by the need to keep these two genomes dancing in time. The pressure to maintain this “mitonuclear match” influences why species stay separate, why we typically have two sexes, how many offspring we produce, and how we age.

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This post was originally published last year. I’m travelling for a few weeks, so I’m reloading some of my favourite stories from 2011. Normal service will resume when I get back.

It couldn’t be easier to make sweeping edits on a computer document. If I were so inclined, I could find every instance of the word “genome” in this article and replace it with the word “cake”. Now, a team of scientists from Harvard Medical School and MIT have found a way to do similar trick with DNA. Geneticists have long been able to edit individual genes, but this group has developed a way of rewriting DNA en masse, turning the entire genome of a bacterium into an “editable and evolvable template”.

Their success was possible because the same genetic code underlies all life. The code is written in the four letters (nucleotides) that chain together to form DNA: A, C, G and T. Every set of three letters (or ‘codon’) corresponds to a different amino acid, the building blocks of proteins. For example, GCA codes for alanine; TGT means cysteine. The chain of letters is translated into a chain of amino acids until you get to a ‘stop codon’. These special triplets act as full stops that indicate when a protein is finished.

This code is virtually the same in every gene on the planet. In every human, tree and bacterium, the same codons correspond to the same amino acids, with only minor variations. The code also includes a lot of redundancy. Four DNA letters can be arranged into 64 possible triplets, which are assigned to only 20 amino acids and one stop codon. So for example, GCT, GCA, GCC and GCG all code for alanine. And these surplus codons provide enough wiggle room for geneticists to play around with.

Farren Isaacs, Peter Carr and Harris Wang have started to replace every instance of TAG with TAA in the genome of the common gut bacterium Escherichia coli. Both are stop codons, so there’s no noticeable difference to the bacterium – it’s like replacing every word in a document with a synonym. But to the team, the genome-wide swap will eventually free up one of the 64 triplets in the genetic code. And that opens up many possible applications.

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This post was originally published last year. I’m travelling for a few weeks, so I’m reloading some of my favourite stories from 2011. Normal service will resume when I get back.
Over the last three years, a group of scientists have been going round two suburbs of Cairns, Australia, and asking local people if they could release mosquitoes on their properties. Ninety percent said yes. These were no ordinary mosquitoes. They had been loaded with bacteria that stop them from passing on the virus that causes dengue fever.

Dengue fever affects thousands of Queenslanders every year. It is caused by an alliance of two parasites – the dengue virus, and the Aedes aegypti mosquito that spreads it. In an ambitious plan to break this partnership, Scott O’Neill from the University of Queensland turned to yet another parasite – a bacterium called Wolbachia. It infects a wide variety of insects and other arthropods, making it possibly the most successful parasite of all. And it has a habit of spreading with great speed.

Wolbachia is transmitted in the eggs of infected females, so it has evolved many strategies for reaching new hosts by screwing over dead-end males. Sometimes it kills them. Sometimes it turns them into females. It also uses a subtler trick called “cytoplasmic incompatibility“, where uninfected females cannot mate successfully with infected males. This means that infected females, who can mate with whomever they like, enjoy a big advantage over uninfected females, who are more restricted. They lay more eggs, which carry more Wolbachia. Once the bacterium gets a foothold in a population, it tends to spread very quickly.

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This post was originally published last year. I’m travelling for a few weeks, so I’m reloading some of my favourite stories from 2011. Normal service will resume when I get back.

If you walk by a European river on a summer’s day, you might get to hear the animal kingdom’s champion vocalist. His song sounds like a train of chirps, and from a metre away, it’s as loud as whirring power tools. The din is all the more incredible because it is produced by an insect just two millimetres in length – the lesser water boatman, Micronecta scholtzi

Micronecta means “small swimmer” and it is aptly named. It’s among the smallest of the several hundred species of water boatmen that row across the bottom of ponds and streams with paddle-shaped legs. The males are the ones that sing, and they often do so in large choruses to attract the silent females. These songs are famously loud. Even though the insect lives underwater, you can hear its call from the riverbank, several metres away.

Now, Jérôme Sueur from the Natural History Museum in Paris has measured Micronecta’s song using underwater microphones. He found that it the small swimmer is a record-breaker. On average, it reaches 79 decibels, about the level of a ringing phone or a cocktail party. But at its peak, it reaches 105 decibels – more like a car horn, a power tool or a passing subway train.

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This post was originally published last year. I’m travelling for a few weeks, so I’m reloading some of my favourite stories from 2011. Normal service will resume when I get back.

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The wing of a fruit fly, viewed against a white background, looks very ordinary. It is transparent, with no obvious colours except for some small brownish spots. But looks can be deceptive. If you put the wing in front of a black background, it suddenly explodes in a kaleidoscope of colour. Oranges, blues, greens, violets – virtually the entire rainbow dances across the wing, except for red.

A French scientist called Claude Charles Goureau first noticed these vivid hues back in 1843. Since then, they have languished in obscurity, “apparently unnoticed by contemporary biologists”. Whenever new species of wasps or flies are described, their discoverers almost never mention the coloured patterns of the wings. The visible pigments have even been described as “evolution in black and white”. It’s like walking through an art gallery with a blindfold.

Now, Ekaterina Shevtsova from Lund University has taken off the blind. By photographing several species against dark backgrounds, she has revealed a world of hidden colour, rivalling that of more obviously beautiful insects. “The claim that fly and wasp wing patterns are no match for the incredible diversity of colourful butterfly wing patterns is obsolete,” she says.

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Some of you may remember that in September, I flew to Peru for a story I was writing for Wired UK. That story is finally out. It’s about Greg Asner, a scientist who is scanning the Amazon by air, in an effort to study and save it. Here’s how it starts:

A small twin-propeller plane flies over the Amazon rainforest in eastern Peru. The scale of the vegetation is staggering. The tree canopy stretches as far as our eyes can see – an endless array of broccoli florets bounded only by haze and horizon. Greg Asner, 43, Asner has seen the rainforest from this vantage point many times before, but he still stares out the window in rapt fascination.

This patch of forest in the Tambopata National Reserve is luxuriant with life even by the Amazon’s standards. A 50-hectare patch of forest – the size of as many rugby pitches – contains more plant species than the whole of North America. “We might as well be exploring Mars,” says Asner. “You’re looking at areas where no human has ever been. There’s no access.”

Access isn’t a problem for Asner. Behind him are three state-of-the-art sensors of his own devising which, as the plane flies along, takes the forest’s measure. “We’re trying to do something really new,” Asner says. “This world is changing and it requires science that isn’t incremental.” Using the technology he’s developed, Asner is mapping the shape and size of the trees down to individual branches from two kilometres overhead. He can measure the carbon stored in trunks, leaves and soil. He can even identify individual plant species based on the chemicals they contain. With wings and lasers, Asner is conducting one of the most ambitious ecology studies ever staged. He accumulates more data in a single hour than most ecologists glean in a lifetime. With this data, he means to influence governments, steer the course of climate-change treaties and save the forests over which he soars.

Asner’s high-flying science has roots on the ground. In 1994, Asner was working in Hawaii for Nature Conservancy, the environmental non-profit organisation. He was frustrated. His seemingly simple task of eliminating invasive plants was thwarted by an equally simple problem – he could not find them. “We were stumbling around in the dark. That’s how I started getting into this, thinking how we could get maps of this stuff.” Satellite data was too coarse and aerial photos uninformative. Eventually, during a PhD position at the University of Colorado, Asner found his answer – airborne sensors. Fifteen years and much head-scratching later, his team has developed AToMS (Airborne Taxonomic Mapping System), a suite of three plane-borne sensors that he describes as “probably the most advanced Earth-mapping system in the world”.

I’m really proud of the piece. It was my first true taste of field reporting, the science is interesting, and it’s a bit structurally more interesting than what I normally do.

For the moment, you’ll have to buy the issue (or subscribe to the iPad edition) to read it. I’d encourage you to do that (support science writing!) but for non-UK people, the story will be online by the end of the month, and I’ll stick a PDF up in a few weeks.

On 25 January 1995, the British merchant vessel SS Lima was sailing through the Indian Ocean when its crew noticed something odd. In the ship’s log, the captain wrote, “A whitish glow was observed on the horizon and, after 15 minutes of steaming, the ship was completely surrounded by a sea of milky-white color.” The eerie glow appeared to “cover the entire sea area, from horizon to horizon . . . and it appeared as though the ship was sailing over a field of snow or gliding over the clouds”. The ship took six hours to sail through it.

These glowing seas have featured in sailor stories for centuries. The crew of the Nautilius encountered the phenomenon in Jules Verne’s Twenty Thousand Leagues Under the Sea. And in 2006, Steven Miller actually managed to recover satellite images of the very same patch seen by the crew of the SS Lima – it stretched over 15,000 square kilometres, the size of Connecticut or Yorkshire.

The glowing waters are the work of bioluminescent bacteria – microbes that can produce their own light. They are found throughout the oceans, although usually in smaller numbers than the giant bloom responsible for the SS Lima’s sighting. In many cases, they form partnerships with animals like fish and squid, taking up residence inside their hosts and paying their rent by providing light for navigation or defence.

But many glowing bacteria live freely in the open ocean, and they glow nonetheless. Creating light takes energy, and it’s not something that’s done needlessly. So why do the bacteria shine? One of the most common answers – and one that Miller proposed to explain his satellite images – is that the bacteria are screaming “Eat me!” at passing fish. A fish’s guts are full of nutrients, and it can carry bacteria across large distances. The bacteria, by turning themselves into glowing bait, get a lift and a meal.

This idea has been around for more than three decades, but it has never actually been tested. Margarita Zarubin from the Interuniversity Institute for Marine Sciences has finally done so.

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Top picks

Nature and Science have been asked to withhold data on lab-made strains of flu by US govt. Carl Zimmer analyses the risks.

The last paragraph in this piece on radioactive spider-webs by Sally Adee is my favourite end to a piece. Ever

There are endless Best Of lists this year, but do have a look at The Browser’s choice of 48 top articles. They have exceedingly good taste.

Zeno’s Advent Calendar.

Do read Maryn McKenna’s wonderful piece on sepsis (and a woman who overcame it).

A fantastic animated history of fossil fuels – 300 years in 5 mins

The price of superstition: how traditional Chinese medicine is a threat to wildlife

How much does the internet weigh? Robert Krulwich is wonderful. Don’t miss: “Look what weightlessness can do”

Some of my favourite science writers – Ann Finkbeiner, Deborah Blum and Jennifer Ouellette – came together for a series on the science of mysteries. Don’t miss it.

War reporter discovers that he has Huntington’s: I will die the most horrible death

Social Networks Matter: Friends Increase the Size of Your Brain, by Eric Michael Johnson

Cloning vs. conservation: viable strategy, flawed fantasy, or Swiftian modest proposal? Great piece by John Rennie

How big is Saturn? This staggering picture will give you an idea

Jonah Lehrer speaks of a “fundamental mismatch between how the world works & how we think about the world”. And Elie Dolgin replies at Nature Medicine.

That’s the answer to light pollution: a dictatorship. Satellite images captures Kim Jong Il’s legacy.

Bizarre Kelvin-Helmholtz Waves Appear Over Alabama

World’s oldest rocks could weigh a man down. Great story. Worth it for the one para that sums 4.5bn yrs of history

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The wonderful site Longreads is collating people’s picks of the best long features of the year. Some say that the internet is triggering a renaissance for long-form writing and I very much agree. Over the past 12 days, I’ve been tweeting my picks and the full list should be up soon. Here it is:

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The world of science offers great opportunities for journalists to flex their writing muscles by fusing rich storytelling and reporting with deft explanatory skill. After all, what could make for better stories than intelligent people trying to understand how the world works?

Here are my top dozen stories from the year, originally tweeted as daily treats in the run-up to Christmas. Yes, I know everyone else has picked five, but we bloggers hate word restrictions – I’ll pick my Top 67 of 2011 and you’ll like it. Each of these features left a firm impression so, taking my lead from Jodi Ettenberg, each choice comes with a note about where I was when I read it.

Here they are, in no particular order:

The Mystery of the Canadian Whiskey Fungus by Adam Rogers (Wired; read at my desk during an uneventful work day)

This is a superb whodunit featuring James Scott, the Sherlock Holmes of fungus – an old-school scientist in the modern world, trying to solve the mystery of the “angel’s share”. It’s packaged with confident wit and vivid, sensory prose (check out that lede), and Rogers finds space to take in a brief history of distillation and a look at the dying art of mycology. The best piece about fungus you’ll likely ever read.

Could Conjoined Twins Share a Mind? by Susan Dominus (New York Times, read in a Lake District cottage)

Tatiana and Kristina Hogan are four-year-old twins, joined at the head. Over the course of five days spent with their family, Dominus asks whether they share their thoughts and senses. It’s a moving and thoughtful piece about neuroscientists struggling to explain a bizarre phenomenon, and a family raising their unique members. It is also, of course, a portrait of two extraordinary girls. By the end of the piece, you feel privileged to have met them, if only in words.

A man-made world, by Oliver Morton (Economist; read in an Islington cafe)

There is a staggering density of ideas in this piece about humanity’s impact on our world. In sentences, Morton encapsulates issues that other writers could dwell on for entire books.

The Possibilian by Burkhard Bilger (New Yorker, read on a Boston subway train)

Bilger tells the story of time-lord David Eagleman, a man who collects jokes and anecdotes, chucks volunteers off tall buildings, counts Brian Eno as a research collaborator, and studies how our brain perceives the passage of time. It is a nigh-perfect blend of solid protagonist, fascinating science, and rich, biographical reporting,

The Mouse Trap, by Daniel Engber (Slate, read on a plane to Cairo)

To write one great feature about laboratory rats may be regarded as skill; to write two looks like vanity; to write three looks like genius. In this trinity of long-reads, Engber discusses why our reliance on fat, lazy rats might be holding back medical progress,  how a strain known as Black-6 came to dominate research, and how a blind naked “anti-mouse” could be our secret weapon against cancer.

Number One with a Bullet by Rowan Jacobsen (Outside, read in Heathrow airport)

In India’s lush Kaziranga National Park, a new policy allows rangers to shoot wildlife poachers on sight. As a result, rhinos and tigers are thriving. Jacobsen introduces us to guards, conservationists and poachers to find deeper stories beyond a simple heroes-versus-villains narrative. This is essentially a superlative piece of war reporting, but with tigers.

Autistic and Seeking a Place in an Adult World by Amy Harmon (New York Times, read in Heathrow airport, immediately after Jacobsen’s piece)

Autism gets a lot of column inches, but usually in the context of silly controversies and far-off medical promises, none of which tell you anything about people with autism themselves. For that reason, Harmon’s take on Justin Canha, a young autistic man trying to find his place in the world, is wonderfully refreshing. It’s eye-opening, compassionate, and features a masterful use of dialogue. It took a year to report, which shows.

E.O.Wilson’s Theory of Everything by Howard French (Atlantic, read on the Victoria Line between Vauxhall and King’s Cross)

How do you write a worthy profile of E.O.Wilson, a man whose work spans decades and whose own writing is tinged with greatness? Apparently, you ask Howard French. Controversies over Wilson’s latest theories notwithstanding, French crafts a portrait of an inspirational figure, entranced by nature at the age of 82 as a boy would be at the age of 8. It also has the year’s best final line.

Deep Intellect: Inside the mind of the octopus by Sy Montgomery (Orion; read in bed)

Octopuses must be some of the easiest animals to write about captivatingly. They have acute intelligence, alien physique and a wondrous array of superpowers. But Montgomery does much more with this piece, which invites you to consider what life must be like with an utterly different mind and body. She is less narrating a natural history programme as inviting you to meet a friend. By the end, you get the feeling that Montgomery has slightly fallen in love with the octopus and that it’s really quite okay if you have too.

The Human Lake by Carl Zimmer (Loom, read on a bus heading for Waterloo)

The best science writers can see their beat through wide-angle lenses, finding common themes that run through seemingly disparate areas. This is a prime example of that skill – a long-form blog post that goes from the residents of a Connecticut lake to those within human intestines, told in Zimmer’s trademark simple-but-beautiful brand of storytelling.

Beautiful brains by David Dobbs (National Geographic, read on my sofa)

Starting with a great lede where his boy-racer son gets thrown in jail, Dobbs unpicks the impulsive, maddening teenage brain in his standard mix of pithy explanations and colloquial flourishes. You’re not reading a piece in National Geographic; you’re sitting by a campfire while a professor tells you a story.

What Made This University Researcher Snap? by Amy Wallace (Wired, read in a burrito joint)

In 2010, scientist Amy Bishop gunned down six of her colleagues at the University of Alabama. Just over a year later, Amy Wallace explores what made her snap. It is consistently gripping, often chilling, and frankly impossible to stop reading after the segment about her brother. It’s also the type of piece that is so intensely reported that it almost hurts to think about the rest of the iceberg.