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by Helen Thomson A brain implant that can decode what someone wants to do has allowed a man paralysed from the neck down to control a robotic arm with unprecedented fluidity – and enjoy a beer at his own pace. Erik Sorto was left unable to move any of his limbs after an accident severed his spinal cord 12 years ago. People with similar injuries have previously controlled prosthetic limbs using implants placed in their motor cortex – an area of the brain responsible for the mechanics of movement. This is far from ideal because it results in delayed, jerky motions as the person thinks about all the individual aspects of the movement. When reaching for a drink, for example, they would have to think about moving their arm forward, then left, then opening their hand, then closing their hand around the cup and so on. Richard Andersen at the California Institute of Technology in Pasadena and his colleagues hoped they could achieve a more fluid movement by placing an implant in the posterior parietal cortex – a part of the brain involved in planning motor movements. "We thought this would allow us to decode brain activity associated with the overall goal of a movement – for example, 'I want to pick up that cup', rather than the individual components," said Anderson at the NeuroGaming Conference in San Francisco, California, where he presented the work this month. © Copyright Reed Business Information Ltd.
Link ID: 20972 - Posted: 05.23.2015
Nala Rogers Alzheimer’s disease may have evolved alongside human intelligence, researchers report in a paper posted this month on BioRxiv1. The study finds evidence that 50,000 to 200,000 years ago, natural selection drove changes in six genes involved in brain development. This may have helped to increase the connectivity of neurons, making modern humans smarter as they evolved from their hominin ancestors. But that new intellectual capacity was not without cost: the same genes are implicated in Alzheimer's disease. Kun Tang, a population geneticist at the Shanghai Institutes for Biological Sciences in China who led the research, speculates that the memory disorder developed as ageing brains struggled with new metabolic demands imposed by increasing intelligence. Humans are the only species known to develop Alzheimer's; the disease is absent even in closely related primate species such as chimpanzees. Tang and his colleagues searched modern human DNA for evidence of this ancient evolution. They examined the genomes of 90 people with African, Asian or European ancestry, looking for patterns of variation driven by changes in population size and natural selection. Marked by selection The analysis was tricky, because the two effects can mimic each other. To control for the effects of population changes ― thereby isolating the signatures of natural selection — the researchers estimated how population sizes changed over time. Then they identified genome segments that did not match up with the population history, revealing the DNA stretches that were most likely shaped by selection. © 2015 Nature Publishing Group
Richard A. Friedman AMERICANS disapprove of marital infidelity. Ninety-one percent of them find it morally wrong, more than the number that reject polygamy, human cloning or suicide, according to a 2013 Gallup poll. Yet the number of Americans who actually cheat on their partners is rather substantial: Over the past two decades, the rate of infidelity among married men has been pretty constant at around 21 percent, while the percentage of married women who admitted to cheating has mostly hovered between 10 and 15 percent, according to the General Social Survey at the University of Chicago’s independent research organization, NORC. We are accustomed to thinking of sexual infidelity as a symptom of an unhappy relationship, a moral flaw or a sign of deteriorating social values. When I was trained as a psychiatrist we were told to look for various emotional and developmental factors — like a history of unstable relationships or a philandering parent — to explain infidelity. But during my career, many of the questions we asked patients were found to be insufficient because for so much behavior, it turns out that genes, gene expression and hormones matter a lot. Now that even appears to be the case for infidelity. We have long known that men have a genetic, evolutionary impulse to cheat, because that increases the odds of having more of their offspring in the world. But now there is intriguing new research showing that some women, too, are biologically inclined to wander, although not for clear evolutionary benefits. Women who carry certain variants of the vasopressin receptor gene are much more likely to engage in “extra pair bonding,” the scientific euphemism for sexual infidelity. © 2015 The New York Times Company
By Jason G. Goldman In 1970 child welfare authorities in Los Angeles discovered that a 14-year-old girl referred to as “Genie” had been living in nearly total social isolation from birth. An unfortunate participant in an unintended experiment, Genie proved interesting to psychologists and linguists, who wondered whether she could still acquire language despite her lack of exposure to it. Genie did help researchers better define the critical period for learning speech—she quickly acquired a vocabulary but did not gain proficiency with grammar—but thankfully, that kind of case study comes along rarely. So scientists have turned to surrogates for isolation experiments. The approach is used extensively with parrots, songbirds and hummingbirds, which, like us, learn how to verbally communicate over time; those abilities are not innate. Studying most vocal-learning mammals—for example, elephants, whales, sea lions—is not practical, so Tel Aviv University zoologists Yosef Prat, Mor Taub and Yossi Yovel turned to the Egyptian fruit bat, a vocal-learning species that babbles before mastering communication, as a child does. The results of their study, the first to raise bats in a vocal vacuum, were published this spring in the journal Science Advances. Five bat pups were reared by their respective mothers in isolation, so the pups heard no adult conversations. After weaning, the juveniles were grouped together and exposed to adult bat chatter through a speaker. A second group of five bats was raised in a colony, hearing their species' vocal interactions from birth. Whereas the group-raised bats eventually swapped early babbling for adult communication, the isolated bats stuck with their immature vocalizations well into adolescence. © 2015 Scientific American
By Meeri Kim The dangers of concussions, caused by traumatic stretching and damage to nerve cells in the brain that lead to dizziness, nausea and headache, has been well documented. But ear damage that is sometimes caused by a head injury has symptoms so similar to the signs of a concussion that doctors may misdiagnose it and administer the wrong treatment. A perilymph fistula is a tear or defect in the small, thin membranes that normally separate the air-filled middle ear from the inner ear, which is filled with a fluid called perilymph. When a fistula forms, tiny amounts of this fluid leak out of the inner ear, an organ crucial not only for hearing but also for balance. Losing even a few small drops of perilymph leaves people disoriented, nauseous and often with a splitting headache, vertigo and memory loss. While most people with a concussion recover within a few days, a perilymph fistula can leave a person disabled for months. There is some controversy around perilymph fistula due to its difficulty of diagnosis — the leak is not directly observable, but rather identified by its symptoms. However, it is generally accepted as a real condition by otolaryngologists and sports physicians, and typically known to follow a traumatic event. But concussions — as well as post-concussion syndrome, which is marked by dizziness, headache and other symptoms that can last even a year after the initial blow — also occur as the result of such an injury.
I’m fairly new to San Francisco, so I’m still building my mental database of restaurants I like. But this weekend, I know exactly where I’m heading to for dinner: Nick’s Crispy Tacos. Then, when I get home, I’m kicking back to a documentary I’ve never heard of, a Mongolian drama called The Cave of the Yellow Dog. An artificially intelligent algorithm told me I’d enjoy both these things. I’d like the restaurant, the machine told me, because I prefer Mexican food and wine bars “with a casual atmosphere,” and the movie because “drama movies are in my digital DNA.” Besides, the title shows up around the web next to Boyhood, another film I like. Nara Logics, the company behind this algorithm, is the brainchild (pun intended) of its CTO and cofounder, Nathan Wilson, a former research scientist at MIT who holds a doctorate in brain and cognitive science. Wilson spent his academic career and early professional life immersed in studying neural networks—software that mimics how a human mind thinks and makes connections. Nara Logics’ brain-like platform, under development for the past five years, is the product of all that thinking.. The Cambridge, Massachusetts-based company includes on its board such bigwig neuroscientists as Sebastian Seung from Princeton, Mriganka Sur from MIT, and Emily Hueske of Harvard’s Center for Brain and Science. So what does all that neuroscience brain power have to offer the tech world, when so many Internet giants—from Google and Facebook to Microsoft and Baidu—already have specialized internal teams looking to push the boundaries of artificial intelligence? These behemoths use AI to bolster their online services, everything from on-the-fly translations to image recognition services. But to hear Wilson tell it, all that in-house work still leaves a large gap—namely, all the businesses and people who could benefit from access to an artificial brain but can’t build it themselves. “We’re building a pipeline, and taking insights out of the lab to intelligent, applied use cases,” Wilson tells WIRED. “Nara is AI for the people.”
Link ID: 20967 - Posted: 05.23.2015
Carl Zimmer Octopuses, squid and cuttlefish — a group of mollusks known as cephalopods — are the ocean’s champions of camouflage. Octopuses can mimic the color and texture of a rock or a piece of coral. Squid can give their skin a glittering sheen to match the water they are swimming in. Cuttlefish will even cloak themselves in black and white squares should a devious scientist put a checkerboard in their aquarium. Cephalopods can perform these spectacles thanks to a dense fabric of specialized cells in their skin. But before a cephalopod can take on a new disguise, it needs to perceive the background that it is going to blend into. Cephalopods have large, powerful eyes to take in their surroundings. But two new studies in The Journal Experimental Biology suggest that they have another way to perceive light: their skin. It’s possible that these animals have, in effect, evolved a body-wide eye. When light enters the eye of a cephalopod, it strikes molecules in the retina called opsins. The collision starts a biochemical reaction that sends an electric signal from the cephalopod’s eye to its brain. (We produce a related form of opsins in our eyes as well.) In 2010, Roger T. Hanlon, a biologist at the Marine Biological Laboratory in Woods Hole, Mass., and his colleagues reported that cuttlefish make opsins in their skin, as well. This discovery raised the tantalizing possibility that the animals could use their skin to sense light much as their eyes do. Dr. Hanlon teamed up with Thomas W. Cronin, a visual ecologist at the University of Maryland Baltimore County, and his colleagues to take a closer look. © 2015 The New York Times Company
Athletes who lose consciousness after concussions may be at greater risk for memory loss later in life, a small study of retired National Football League players suggests. Researchers compared memory tests and brain scans for former NFL players and a control group of people who didn't play college or pro football. After concussions that resulted in lost consciousness, the football players were more likely to have mild cognitive impairment and brain atrophy years later. "Our results do suggest that players with a history of concussion with a loss of consciousness may be at greater risk for cognitive problems later in life," senior study author Munro Cullum, chief of neuropsychology at the University of Texas Southwestern Medical Center in Dallas, said by email. "We are at the early stages of understanding who is actually at risk at the individual level." Cullum and colleagues recruited 28 retired NFL players living in Texas: eight who were diagnosed with mild cognitive impairment and 20 who didn't appear to have any memory problems. They ranged in age from 36 to 79, and were an average of about 58 years old. All but three former athletes experienced at least one concussion, and they typically had more than three. Researchers compared these men to 27 people who didn't play football but were similar in age, education, and mental capacity to the retired athletes, including six with cognitive impairment. These men were 41 to 77 years old, and about 59 on average. ©2015 CBC/Radio-Canada
Scientists at Mayo Clinic, Jacksonville, Florida created a novel mouse that exhibits the symptoms and neurodegeneration associated with the most common genetic forms of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS, Lou Gehrig’s disease), both of which are caused by a mutation in the a gene called C9ORF72. The study was partially funded by the National Institutes of Health and published in the journal Science. More than 30,000 Americans live with ALS, which destroys nerves that control essential movements, including speaking, walking, breathing and swallowing. After Alzheimer’s disease, FTD is the most common form of early onset dementia. It is characterized by changes in personality, behavior and language due to loss of neurons in the brain’s frontal and temporal lobes. Patients with mutations in the chromosome 9 open reading frame 72 (C9ORF72) gene have all or some symptoms associated with both disorders. “Our mouse model exhibits the pathologies and symptoms of ALS and FTD seen in patients with theC9ORF72 mutation,” said the study’s lead author, Leonard Petrucelli, Ph.D., chair and Ralph and Ruth Abrams Professor of the Department of Neuroscience at Mayo Clinic, and a senior author of the study. “These mice could greatly improve our understanding of ALS and FTD and hasten the development of effective treatments.” To create the model, Ms. Jeannie Chew, a Mayo Graduate School student and member of Dr. Petrucelli’s team, injected the brains of newborn mice with a disease-causing version of the C9ORF72 gene. As the mice aged, they became hyperactive, anxious, and antisocial, in addition to having problems with movement that mirrored patient symptoms.
By SINDYA N. BHANOO Male Java sparrows are songbirds — and, scientists reported on Wednesday, natural percussionists. The sparrows click their bills against a hard surface while singing. That clicking is done in coordination with the song, much as a percussion instrument accompanies a melody. Researchers at Hokkaido University in Japan observed the birds producing clicks frequently toward the beginning of their songs and around specific notes. Birds that were related produced similar percussive patterns, but whether this behavior is learned or innate is unclear. Next the scientists, who described their findings on Wednesday in the journal PLOS One, would like to know whether male sparrows use bill clicks during courtship communication. © 2015 The New York Times Company
by Karl Gruber "As clever as a guppy" is not a huge compliment. But intelligence does matter to these tropical fish: big-brained guppies are more likely to outwit predators and live longer than their dim-witted peers. Alexander Kotrschal at Stockholm University, Sweden, and his colleagues bred guppies (Poecilia reticulata) to have brains that were bigger or smaller than average. His team previously showed that bigger brains meant smarter fish. When put in an experimental stream with predators, big-brained females were eaten about 13 per cent less often than small-brained ones. There was no such link in males, and the researchers suspect that their bright colours may counter any benefits of higher intelligence. They did find, Kotrschal says , that large-brained males were faster swimmers and better at learning and remembering the location of a female. "This is exciting because it confirms a critical mechanism for brain size evolution," says Kotrschal. It shows, he adds, that interactions between predator and prey can affect brain size. It might seem obvious that bigger brains would help survival. Yet previous research simply found a correlation between the two, leaving the possibility open that some third factor may have been driving the effect. Now, direct brain size manipulation allowed Kotrschal's team to pin it down as a cause of better survival. "This is the first time anyone has tested whether a larger brain confers a survival benefit," says Kotrschal. "The fact that large-brained females survived better in a naturalistic setting is the first experimental proof that a larger brain is beneficial for the fitness of its bearer. This is like watching evolution happen and shows how brain size evolves." © Copyright Reed Business Information Ltd.
Stacey Vanek Smith I'm in a booth with a computer program called Ellie. She's on a screen in front of me. Ellie was designed to diagnose post-traumatic stress disorder and depression, and when I get into the booth she starts asking me questions — about my family, my feelings, my biggest regrets. Emotions seem really messy and hard for a machine to understand. But Skip Rizzo, a psychologist who helped design Ellie, thought otherwise. When I answer Ellie's questions, she listens. But she doesn't process the words I'm saying. She analyzes my tone. A camera tracks every detail of my facial expressions. The doctor may see you now "Contrary to popular belief, depressed people smile as many times as non-depressed people," Rizzo says. "But their smiles are less robust and of less duration. It's almost like polite smiles rather than real, robust, coming from your inner-soul type of a smile." Ellie compares my smile to a database of soldiers who have returned from combat. Is my smile genuine? Is it forced? Ellie also listens for pauses. She watches to see whether I look off to the side or down. If I lean forward, she notices. All this analysis seems to work: In studies, Ellie could detect signs of PTSD and depression about as well as a large pool of psychologists. Jody Mitic served with the Canadian forces in Afghanistan. He lost both of his feet to a bomb. And Mitic remembers that Ellie's robot-ness helped him open up. "Ellie seemed to just be listening," Mitic says. "A lot of therapists, you can see it in their eyes, when you start talking about some of the grislier details of stuff that you might have seen or done, they are having a reaction." © 2015 NPR
Dan Sung A 10-year study has revealed a startling link between high levels of anxiety and an increased risk of death from liver disease. The research, carried out by scientists at the University of Edinburgh, took account for obvious sociological and physiological factors such as alcohol consumption, obesity, diabetes and class, but still the data pointed to a clear relationship between the psychological conditions of stress and depression and the physical health of the hepatic system. There were over 165,000 participants surveyed for mental distress. They were each tracked for over a decade during which time the causes of death for those who passed on were recorded and categorised. What was found was that those who’d scored highly for signs of depression and stress were far more likely to suffer fatal liver disease. “This study provides further evidence for the important links between mind and body, and of the damaging effects psychological distress can have on physical wellbeing,” said Dr Tom Russ of the Centre for Clinical Brain Sciences. The work did not uncover any reasons for direct cause and effect but is the first to identify such a link between mental states and liver damage. Previous research has described how psychological conditions can lead to increased risk of cardiovascular disease which, in turn, may develop into obesity, raised blood pressure and then eventually to liver failure but, with this methodology controlling for such factors, it appears that the link is more direct than was previously thought.
by Bas den Hond Watch your language. Words mean different things to different people – so the brainwaves they provoke could be a way to identify you. Blair Armstrong of the Basque Center on Cognition, Brain, and Language in Spain and his team recorded the brain signals of 45 volunteers as they read a list of 75 acronyms – such as FBI or DVD – then used computer programs to spot differences between individuals. The participants' responses varied enough that the programs could identify the volunteers with about 94 per cent accuracy when the experiment was repeated. The results hint that such brainwaves could be a way for security systems to verify individuals' identity. While the 94 per cent accuracy seen in this experiment would not be secure enough to guard, for example, a room or computer full of secrets, Armstrong says it's a promising start. Techniques for identifying people based on the electrical signals in their brain have been developed before. A desirable advantage of such techniques is that they could be used to verify someone's identity continuously, whereas passwords or fingerprints only provide a tool for one-off identification. Continuous verification – by face or ear recognition, or perhaps by monitoring brain activity – could in theory allow someone to interact with many computer systems simultaneously, or even with a variety of intelligent objects, without having to repeatedly enter passwords for each device. © Copyright Reed Business Information Ltd
By Susan Cosier Once a memory is lost, is it gone forever? Most research points to yes. Yet a study published in the online journal eLife now suggests that traces of a lost memory might remain in a cell's nucleus, perhaps enabling future recall or at least the easy formation of a new, related memory. The current theory accepted by neurobiologists is that long-term memories live at synapses, which are the spaces where impulses pass from one nerve cell to another. Lasting memories are dependent on a strong network of such neural connections; memories weaken or fade if the synapses degrade. In the new study, researchers at the University of California, Los Angeles, studied sea slugs' neurons in a cell culture dish. Over several days the neurons spontaneously formed a number of synapses. The scientists then administered the neurotransmitter serotonin to the neurons, causing them to create many more synapses—the same process by which a living creature would form a long-term memory. When they inhibited a memory-forming enzyme and checked the neurons after 48 hours, the number of synapses had returned to the initial number—but they were not the same individual synapses as before. Some of the original and some of the new synapses retracted to create the exact number the cells started with. The finding is surprising because it suggests that a nerve cell body “knows” how many synapses it is supposed to form, meaning it is encoding a crucial part of memory. The researchers also ran a similar experiment on live sea slugs, in which they found that a long-term memory could be totally erased (as gauged by its synapses being destroyed) and then re-formed with only a small reminder stimulus—again suggesting that some information was being stored in a neuron's body. © 2015 Scientific American
Keyword: Learning & Memory
Link ID: 20958 - Posted: 05.20.2015
by Clare Wilson Does this qualify as irony? Our bodies need iron to be healthy – but too much could harm our brains by bringing on Alzheimer's disease. If that's the case, measuring people's brain iron levels could help identify those at risk of developing the disease. And since we already have drugs that lower iron, we may be able to put the brakes on. Despite intense efforts, the mechanisms behind this form of dementia are still poorly understood. For a long time the main suspect has been a protein called beta-amyloid, which forms distinctive plaques in the brain, but drugs that dissolve it don't result in people improving. Not so good ferrous Studies have suggested that people with Alzheimer's also have higher iron levels in their brains. Now it seems that high iron may hasten the disease's onset. Researchers at the University of Melbourne in Australia followed 144 older people who had mild cognitive impairment for seven years. To gauge how much iron was in their brains, they measured ferritin, a protein that binds to the metal, in their cerebrospinal fluid. For every nanogram per millilitre people had at the start of the study, they were diagnosed with Alzheimer's on average three months earlier. The team also found that the biggest risk gene for Alzheimer's, ApoE4, was strongly linked with higher iron, suggesting this is why carrying the gene makes you more vulnerable. Iron is highly reactive, so it probably subjects neurons to chemical stress, says team member Scott Ayton. © Copyright Reed Business Information Ltd
Link ID: 20957 - Posted: 05.20.2015
By PAM BELLUCKM The largest analysis to date of amyloid plaques in people’s brains confirms that the presence of the substance can help predict who will develop Alzheimer’s and determine who has the disease. Two linked studies, published Tuesday in JAMA, also support the central early role in Alzheimer’s of beta amyloid, the protein that creates plaques. Data from nearly 9,500 people on five continents shows that amyloid can appear 20 to 30 years before symptoms of dementia, that the vast majority of Alzheimer’s patients have amyloid and that the ApoE4 gene, known to increase Alzheimer’s risk, greatly accelerates amyloid accumulation. The findings also confirm that amyloid screening, by PET scan or cerebral spinal fluid test, can help identify people for clinical trials of drugs to prevent Alzheimer’s. Such screening is increasingly used in research. Experts say previous trials of anti-amyloid drugs on people with dementia failed because their brains were already too damaged or because some patients, not screened for amyloid, may not have had Alzheimer’s. “The papers indicate that amyloid imaging is important to be sure that the drugs are being tested on people who have amyloid,” said Dr. Roger Rosenberg, the director of the Alzheimer’s Disease Center at the University of Texas Southwestern Medical Center at Dallas, who wrote an editorial about the studies. Dr. Samuel Gandy, an Alzheimer’s researcher at Mount Sinai Hospital, who was not involved in the research, said doctors “can feel fairly confident that amyloid is due to Alzheimer’s.” But he and others cautioned against screening most people without dementia because there is not yet a drug that prevents or treats Alzheimer’s, and amyloid scans are expensive and typically not covered by insurance. © 2015 The New York Times Company
Link ID: 20956 - Posted: 05.20.2015
by Ashley Yeager This guest post is by SN's web producer Ashley Yeager, who can't remember ever not knowing how to swim. Sometimes my brother-in-law will scoop up my 2-year-old niece and fly her around like Superwoman. She’ll start kicking her legs and swinging her arms like she’s swimming — especially when we say, “paddle, paddle, paddle.” My niece, Baby D, loves the water. She often looks like one of the kids captured in famed photographer Seth Casteel’s new book, Underwater Babies. But she probably won’t remember her first trips to the pool — she was only a few months old when her mom first took her swimming. Part of my sister’s reasoning for such an early start was standard water safety. Every day in the United States, accidental drowning claims the lives of two children under the age of 14 years. Our family spends a lot of time at the pool and the beach, so making sure Baby D is protected is a priority. But there’s another reason my sister was keen to get Baby D to the pool. Loosely based on something our mother told us, it’s that learning to swim early in life may give kids a head start in developing balance, body awareness and maybe even language and math skills. Mom may have been right. A multi-year study released in 2012 suggests that kids who take swim lessons early in life appear to hit certain developmental milestones well before their nonswimming peers. In the study, Australian researchers surveyed about 7,000 parents about their children’s development and gave 177 kids aged 3 to 5 years standard motor, language, memory and attention tests. Compared with kids who didn’t spend much time in the water, kids who had taken swim lessons seemed to be more advanced at tasks like running and climbing stairs and standing on their tiptoes or on one leg, along with drawing, handling scissors and building towers out of blocks. © Society for Science & the Public 2000 - 2015.
An octopus filmed off the coast of Kalaoa in Hawaii has shown that even cephalopods can get into a game of peekaboo. In the footage, shot last month by the GoPro camera of diver Timothy Ewing, the octopus bobs up and down behind a rock as a Ewing does the same in an effort to take the animal's picture. It's clear from the video that the octopus is wary of Ewing and his big, light-equipped camera — but the animal is also very curious. “Octopus are one of the more intelligent creatures in the ocean. Sometimes they are too curious for their own good. If you hide from them they will come out and look for you," the diver wrote in his online posting of the video. Ewing explained to CaliforniaDiver.com that the encounter wasn't limited to the time captured on his GoPro. "I was interacting with that octopus for about 10 minutes before I took the video," Ewing told CaliforniaDiver.com. "I normally mount my GoPro to my big camera housing, however I always carry a small tripod with me to use with the GoPro for stationary shots like this or selfie videos." The octopus, found worldwide in tropical, subtropical and temperate areas, is known for its smarts and striking ability to camouflage itself. When it feels threatened, pigment cells in its skin allow it to change color instantly to blend in with its surroundings. The animals can also adapt their skin texture and body posture to further match their background. © 2015 Discovery Communications, LLC.
by Ashley Yeager New Caledonian crows are protective of their tools. The birds safeguard the sticks they use to find food and become even more careful with the tools as the cost of losing them goes up. Researchers videotaped captive and wild Corvus moneduloides crows and tracked what the birds did with their sticks. In between eating, the birds tucked the tools under their toes or left them in the holes they were probing. When higher up in the trees, the birds dropped the tools less often and were more likely to leave them in the holes they were probing than when they were on the ground. The finding, published May 20 in the Proceedings of the Royal Society B, shows how tool-protection tactics can prevent costly losses that could keep the crows from chowing down. © Society for Science & the Public 2000 - 2015