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Archive for November, 2012
Spaun, the simulated brain that performs simple tasks
There have been many attempts to create a virtual brain, by simulating massive networks of neurons. But brains aren’t just piles of neurons. They also do things. They perceive. They reason. They solve tasks. Enter Spaun – the first brain simulation that actually shows simple behaviour, from recognising and copying a number, to solving simple reasoning problems.
It simulates 2.5 million virtual neurons, including the electricity that course through them, and the signalling chemicals that pass between them. It’s almost as accurate as the average humans at 8 separate tasks and, rather delightfully, reproduces many of our strange quirks – like the tendency to remember items at the start and end of a list.
I’ve written about Spaun for Nature News. Head over there for more
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We’re back… but comments have changed.
The good news: the blogs are back online, and speeds are back to normal. Thanks for your patience.
The bad news: the comment system has now changed so that you can only comment after you have created an account and signed in. This overwrites my old comment policy of being able to comment freely once your first comment is approved.
For the record, I found out about this change on Monday and I’m not happy about it. If you feel the same, just bear with me – I’ll have an update in a week or so. Or feel free to voice your views by… erm… registering and leaving a comment, or sending me an email.
In the meantime, plenty of cool science coming up…
DNA Lego bricks produce nano-sculptures
For tens of thousands of years, humans have created sculptures by carving pieces from a solid block. They have chipped away at stone, metal, wood and ceramics, creating art by subtracting material. Now, a group of scientists from Harvard University have figured out how to do the same thing with DNA.
First, Yonggang Ke builds a solid block of DNA from individual Lego-like bricks. Each one is a single strand of the famous double helix that folds into a U-shape, designed to interlock with four neighbours. You can see what happens in the diagram below, which visualises the strands as two-hole Lego bricks. Together, hundreds of them can anneal into a solid block. And because each brick has a unique sequences, it only sticks to certain neighbours, and occupies a set position in the block.
This means that Ke can create different shapes by leaving out specific bricks from the full set, like a sculptor removing bits of stone from a block. Starting with a thousand-brick block, he carved out 102 different shapes, with complex features like cavities, tunnels, and embossed symbols. Each one is just 25 nanometres wide in any direction, roughly the size of the smallest viruses.
Bear with us…
You may have noticed that Discover has had a redesign. This has been accompanied by a migration to new servers, which means that the site is currently loading slowly, if at all, and that comments aren’t working yet.
Apologies for the inconvenience. If you have any complaints, please leave a comme… never mind.
Enter the hyperparasites – wasps that lay eggs in wasps that lay eggs in caterpillars
(Left by Nina Fatouros, centre by Hans Smid, right by Harald Süpfle)
A very hungry caterpillar munches on a cabbage leaf and sets off an alarm. The plant releases chemicals into the air, signalling that it is under attack. This alarm is intercepted by a wasp, which stings the caterpillar and implants it with eggs. When they hatch, the larval wasps devour their host from the inside, eventually bursting out to spin cocoons and transform into adults. The cabbage (and those around it) are saved, and the wasp—known as a parasitoid because of its fatal body-snatching habits—raises the next generation.
But that’s not the whole story.
Some parasitic wasps are “hyperparasitoids”—they target other parasitoid wasps. And they also track the cabbage’s alarm chemicals, so they can find infected caterpillars. When they do, they lay their eggs on any wasp grubs or pupae that they find. Their young devour the young of the other would-be parasites, in a tiered stack of body-snatching. It’s like a cross between the films Alien and Inception.
Will we ever… make a safe cigarette?
Here’s the 13th piece from my BBC column
There’s an old saying among people who work in public health: Tobacco is the only legal product that, when used as intended, will kill you. Decades of research have thoroughly documented the health problems that result from inhaling tobacco smoke – more than a dozen different types of cancer, heart disease, stroke, emphysema and other respiratory diseases, among others. Are these risks an inevitable part of smoking? Or is there a way of creating safe cigarettes without any of these hazards?
“I think it’s very unlikely,” says Stephen Hecht from the University of Minnesota Cancer Center, who studies tobacco carcinogens – substances that cause cancer. Tobacco smoke is a complex cocktail of at least 4,000 chemicals including at least 70 known carcinogens. No one has made a “cigarette that is significantly decreased in all of these [chemicals] and is still something people would want to smoke, even though the industry has worked on this for around 50 years,” says Hecht. “There’s no indication that it’s possible.”
I've got your missing links right here (24 November 2012)
Top picks
One woman’s craving for sleep led to the discovery of a mystery sleep-inducing chemical. This is an amazing piece. Virginia Hughes is science writing royalty.
Attack of the mutant pupfish: a spectacularly written feature by Hillary Rosner on a bold approach to conservation—hybridising species to save them
Excellent longread on a 50-year quest to find cases of “laughing death” (kuru), which led to the discovery of prions
Animal vision evolved 700 million years ago. This is a *beautifully* written post by Lucas Brouwers. Highly recommend
“Where is your mind?” Tom Stafford on the fine line between cultural & neural networks
Don’t miss Charles Seife’s investigation into how drug company money is influencing scientists.
Nature takes a hard look at its own sexism & commits to do better. Massive kudos to them for this
If you’re 27 or younger, you’ve never experienced a month when the global temperature was colder than the 20thC average
Yet more evidence of Retraction Watch’s continuing effect on scientific integrity. Congrats to Ivan Oransky and Adam Marcus
Check out Gaia Vince’s radio series on the anthropocene.
NatGeo GIFs: it’s like wonder on a loop.
Feather by feather, scientists reconstruct primitive wing of Archaeopterx, a prehistoric bird. By Carolyn Johnson
The story of the portable beetle, with handles that termites can hold, as told by Matthew Cobb the style of Kipling. And then, a follow-up story on a handled wasp!
Hunt for life under Antarctic ice heats up. This is a marvellous quote: “This is the very pinnacle of the science I’ve been doing since the turn of the millennium. Now guess if I’m excited.”
Mankind isn’t a gender-neutral term. Let’s use humanity instead, argues Annaleen Newitz. Lovely piece on etymology
Vaccines: because it’s great when babies don’t sh*t themselves to death. A hard-hitting chart.
Mind-blowing Jennifer Frazer post: Zombified bacteria are a thing.
Troubled bonobo facility reinstates controversial researcher, Sue Savage-Rumbaugh. Great coverage from Kate Wong.
Science/news/writing
Coming soon: Africa, a new 6-part Attenborough series.
British physicist jailed for smuggling 2kg of cocaine into Argentina, says he was duped by bikini model
It’s the final stretch for Ethan Perlstein’s attempt to crowdfund his research on meth addiction. And here’s more cool crowd-funded science, on beetles that dupe super-organisms
DNA has been around for billions of yrs — but that doesn’t mean scientists can’t make it better.
Where did it go? Scientists ‘undiscover’ Pacific island
Bats adjust squeaks to focus sonar http://t.co/l9K0uj3E
DROPBATS! Ancient tree-wombat behaved like a koala http://t.co/nUDCTcvV
“Counting white animals against a white backdrop from a helicopter, over 100,000s of sq.kms, is actually pretty tricky”
It is frankly amazing that the guy behind the “Things I Learned as a Field Biologist” blog is even alive.
Self-filling water bottle that condenses water from the air, modelled on namib desert beetle
Here’s a campaign to stop animal rights groups who are targeting firms that transport animals for medical research
Carin Bondar launches a new web series on animal sex
‘Lonesome George has relatives’
Bora Zivkovic on expertise. I love the point about the difference between a good writer and a seductive writer.
Oliver Morton on the Martian organic molecules scientists have already found and studied
In case you need to sort gorilla sperm from human sperm… Jennifer Ouellette on telling one sperm from another
Physicist Paul Davies is back with his ideas about cancer. Except they’re hogwash. See these rebuttals from Genotripe (“…article offers no new insight & crucially, no actual evidence.”) and PZ Myers.
Google engineer turns vacuum cleaner into dirt-cheap book scanner
Nutrition recession: Families struggle to eat healthily amid rising food bills and shrinking budgets
Gamers prove equal to surgeons in operating robotic surgery tools. But they keep dragon-punching my spleen.
Excellent post by Melanie Tannenbaum on the psychology of the Petraeus affair – much better than the usual tripe in this vein.
Why being able to hold your booze might not be a good thing, but could lead to targeted interventions
Man CT scans and 3D prints own skull, makes art of forensic facial reconstruction
To horn or to sneak? It’s all about balls. Tom Houslay on beetle sex lives.
Winter to be cold, say Met Office to press, with tremendous weariness
Gorillas & humans last shared a common ancestor 10m yrs ago— how do we know that? Nice explainer
“It is quite usual that an amputated penis is tossed out of an open window, where it may be captured by a duck.”
The cost of basic lab equipment is absurd. Can 3D-printing help?
First randomised controlled trial to show spinal cord regeneration in dogs
Nice campaign from Parkinson’s UK – fund research by sponsoring a C. elegans worm for £5/mth
Great website on the incredible Burgess Shale by the Royal Ontario Museum
JNK Nature paper has 3 corrections and counting… Very rich comment thread
BBC makes absurd decision to axe the great popular science radio show, Naked Scientists
On this story on apes and midlife crises, virtually *every* outside comment I’ve seen about this ape-midlife-crisis story has been skeptical & critical
Breast Checking mitt loses fight to prove credibility
‘Super-Jupiter’ Dwarfs Solar System’s Largest Planet. Jupitest?
How birds are used to monitor pollution. They’re like canaries in the coa… wait.
Science isn’t necessarily hard, nor scientists necessarily clever, and both tropes are unhelpful.
Which Bond villain schemes might actually have made economic sense?
Fascinating paper: how the Mian of Papua New Guinea use rivers to represent space & time how education is changing it
This is a thing? DESTROY ALL TICKS. Evidence mounting that tick bites cause unusual allergy to meat
Relocating rattlesnakes as conservation tool for homeowners?
A teacher’s perspective on the study on neuromyths held by teachers
Skeleton might be Richard III; DNA results delayed from December to January. So… winter of discontent?
Heh/wow/huh
Picture taken at London’s Natural History Museum. “We are evolving.” Charles approves.
In which Dean Burnett single-handedly fixes the British economy
“They have pictures on the boxes that mean science.” Humans buying any sh*t with ‘immune system’ written on it
Beautiful Chinese leopard wins wildlife camera-trap photo prize
“Using your brains to think of an idea? That’s the old model.” The Onion on social media “gurus”
WTFs from textbooks.
Excited frog is excited.
Robot spider seeks missing legs
Spiders from Mars! (made of dry ice)
“Irrational hatred of fruit” and other hidden motivations of video game characters
Second cutest book ever! ZooBorns has new book of dangerously adorable baby animals.
Gaze in wonder at Professor Walter Lewins’ best chalk lines.
No fair, I wanna ride a capybara.
Mechanical Arthropods and Insects Made from Watch Parts and Light Bulbs
Oh HAI, baby mantis!
Internet/journalism/society
On dead pigeon’s leg, an unbreakable code
Writer/journalist and scientist are among kids’ dream jobs, proving again that kids are morons 
Della Thomas has an interesting post and survey on self-promotion via Twitter. Here’s my simple guide
Are Japan’s ninjas heading for extinction? Or are they just hiding?
The John McAfee story is unbelizeable
The next generation of touchscreen tech or the emperor’s cumbersome new clothes?
Freelancers, find a home for your science story, by reading what editors want
What does war sound like now?
How many times should the government rebuild at-risk areas? The “retreat” quote is chilling.
Here are 10 golden rules of Twitter
A Q&A about MATTER, the new long-form science publishing initiative
Portraits of politicians made from collages of bits of pornography.
Lord McAlpine plans to Sue 10k Twitter Users
Dystopic, awful read on a possible future for Twitter
This is a shocking example of men who hate strong women. Also: terribly written. Skip to the letter at end
Neurons can silence each other without any direct connections
The chatter in your brain largely depends on special junctions called synapses – meeting places between two neurons, through which they transmit chemical signals or electric currents.
But neurons don’t always need synapses to communicate—some in the antennae of a fly can influence one another without any direct connections. The electric field produced by one can silence its neighbour, like two individuals standing side by side and whispering “Sssssshhhh” at each other.
This phenomenon, known as ephaptic coupling, has been discussed for a long time but it’s always been a bit obscure and arcane. There are very few examples of it, and none where this indirect silencing actually affects an animal’s behaviour. Su has changed that – his study shows that ephaptic coupling affects a fly’s or mosquito’s sense of smell. That knowledge might be useful for protecting crops from hungry insects, or people from disease-carrying ones.
I’ve written about this story for The Scientist, so head over there for more details.
Image by Martin Hauser
Why are stabby mantis shrimps so much slower than punchy ones?
Credit: Professor Roy Caldwell at UC Berkeley.
If you want to find an ocean animal that kills with speed, don’t look to sharks, swordfishes, or barracuda. Instead, try to find a mantis shrimp. These pugilistic relatives of crabs and lobsters attack other animals by rapidly unfurling a pair of arms held under their heads. One group of them—the smashers—have arms that end in heavily reinforced clubs, which can lash out with a top speed of 23 metres per second (50 miles per hour), and hit like a rifle bullet. These powerful hammers can shatter aquarium glass and crab shells alike.
Most research on mantis shrimps focuses on smashers, but these pugilists are in the minority. The majority are “spearers”, whose arms end in a row of fiendish spikes, rather than hard clubs. While the smashers actively search for prey to beat into submission, the spearers are ambush-hunters. They hide in burrows and wait to impale passing victims. They’re Loki to the smashers’ Thor.
Given their differing lifestyles, you might expect the spearers to be faster than the smashers. They rely on quick strikes to kill their prey, and they target fast victims like fish and shrimp rather than the tank-like, slow-moving crabs favoured by smashers. But surprisingly, Maya DeVries from the University of California, Berkeley, found that the fastest spearer strikes at just a quarter of the speed of the fastest smasher.
Wormholes in old books preserve a history of insects
Absence can speak volumes. The lack of sediment in a flat piece of ground—a track—can testify to the footstep of a dinosaur that once walked on it. The lack of minerals in a solid shell—a hole—can reveal the presence of parasite that was once trapped in it. The world’s museums are full of such “trace fossils”, but so are many of the world’s art galleries.
The image above is taken from a woodcut currently residing in Amsterdam’s Rijksmuseum. It was made by etching a pattern into a block of wood, so that the remaining raised edges could be dipped in ink and used to print an image. These woodcuts were the main way of illustrating European books between the 15th and 19th centuries, and were used for at least 7 million different titles.
But as you can see, the print is littered with tiny white holes. These are called wormholes, and inaccurately so—they’re actually the work of beetles. The adults laid their eggs in crevices within the trunks of trees. The grubs slowly bored their way through the wood, eventually transformed into adults, and burrowed their way out of their shelters. The artists who transformed the tree trunks into printing blocks also inherited the exit-holes of the adult beetles, which left small circles of empty whiteness when pressed onto pages.
The beetles only emerged a year or so after the blocks were carved. The holes they left must have been frustrating, but remaking them would have been expensive. So the blocks were kept and reused despite their defects, unless the beetles had really gone to town. The holes they left behind preserve a record of wood-boring beetles, across four centuries of European literature. These holes are trace fossils. They’re evidence of beetle behaviour that’s been printed into old pages, just as dinosaur tracks were printed into the earth.
Now, Blair Hedges from Pennsylvania State University has used these fossils to study the history of the beetles that made them.
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