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Modeling Integrated Cellular Machinery Using Hybrid Petri-Boolean Networks

Modeling Integrated Cellular Machinery Using Hybrid Petri-Boolean Networks | Social Foraging | Scoop.it

The behavior and phenotypic changes of cells are governed by a cellular circuitry that represents a set of biochemical reactions. Based on biological functions, this circuitry is divided into three types of networks, each encoding for a major biological process: signal transduction, transcription regulation, and metabolism. This division has generally enabled taming computational complexity dealing with the entire system, allowed for using modeling techniques that are specific to each of the components, and achieved separation of the different time scales at which reactions in each of the three networks occur. Nonetheless, with this division comes loss of information and power needed to elucidate certain cellular phenomena. Within the cell, these three types of networks work in tandem, and each produces signals and/or substances that are used by the others to process information and operate normally. Therefore, computational techniques for modeling integrated cellular machinery are needed. In this work, we propose an integrated hybrid model (IHM) that combines Petri nets and Boolean networks to model integrated cellular networks. Coupled with a stochastic simulation mechanism, the model simulates the dynamics of the integrated network, and can be perturbed to generate testable hypotheses. Our model is qualitative and is mostly built upon knowledge from the literature and requires fine-tuning of very few parameters. We validated our model on two systems: the transcriptional regulation of glucose metabolism in human cells, and cellular osmoregulation in S. cerevisiae. The model produced results that are in very good agreement with experimental data, and produces valid hypotheses. The abstract nature of our model and the ease of its construction makes it a very good candidate for modeling integrated networks from qualitative data. The results it produces can guide the practitioner to zoom into components and interconnections and investigate them using such more detailed mathematical models.

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With Mindware Upgrades and Cognitive Prosthetics, Humans Are Already Technological Animals

With Mindware Upgrades and Cognitive Prosthetics, Humans Are Already Technological Animals | Social Foraging | Scoop.it
In recent years, the surprising idea that we’ll one day merge with our technology has warily made its way into the mainstream. Often it’s couched in a combination of snark and fear. Why in the world would we want to do that? It’s so inhuman.

That the idea is distasteful isn’t shocking. The imagination rapidly conjures images of Star Trek’s Borg, a nightmarish future when humans and machines melt into a monstrosity of flesh and wires, forever and irrevocably leaving “nature” behind.

But let’s not fool ourselves with such dark fantasies. Humans are already technological animals; tight integration with our inventions is in our nature; and further increasing that integration won’t take place in some distant future—it’s happening now.

To observe our technological attachment, we need simply walk out the door. It’s everywhere, all around us—on the bus or train, at work, at home, in the bathroom, in bed—people gazing into screens, living digital lives right next to their ordinary ones.

In the Matrix, the experience is involuntary, a tool of control and oppression. In our world, it’s voluntary, and mostly about freedom, expansion, and expression. As Jason Silva recently noted, our devices augment our brains, like cognitive prosthetics.
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Explosive synchronization in adaptive and multilayer networks

Explosive synchronization (ES) is nowadays a hot topic of interest in nonlinear science and complex networks. So far, it is conjectured that ES is rooted in the setting of specific microscopic correlation features between the natural frequencies of the networked oscillators and their effective coupling strengths. We show that ES, in fact, is far more general, and can occur in adaptive and multilayer networks also in the absence of such correlation properties. Precisely, we first report evidence of ES in the absence of correlation for networks where a fraction f of the nodes have links adaptively controlled by a local order parameter, and then we extend the study to a variety of two-layer networks with a fraction f of their nodes coupled each other by means of dependency links. In this latter case, we even show that ES sets in, regardless of the differences in the frequency distribution and/or in the topology of connections between the two layers. Finally, we provide a rigorous, analytical, treatment to properly ground all the observed scenario, and to facilitate the understanding of the actual mechanisms at the basis of ES in real-world systems.

 

Explosive synchronization in adaptive and multilayer networks
Xiyun Zhang, Stefano Boccaletti, Shuguang Guan, Zonghua Liu

http://arxiv.org/abs/1410.2986


Via Complexity Digest
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Spectral Signatures of Reorganised Brain Networks in Disorders of Consciousness

Spectral Signatures of Reorganised Brain Networks in Disorders of Consciousness | Social Foraging | Scoop.it
Theoretical advances in the science of consciousness have proposed that it is concomitant with balanced cortical integration and differentiation, enabled by efficient networks of information transfer across multiple scales. Here, we apply graph theory to compare key signatures of such networks in high-density electroencephalographic data from 32 patients with chronic disorders of consciousness, against normative data from healthy controls. Based on connectivity within canonical frequency bands, we found that patient networks had reduced local and global efficiency, and fewer hubs in the alpha band. We devised a novel topographical metric, termed modular span, which showed that the alpha network modules in patients were also spatially circumscribed, lacking the structured long-distance interactions commonly observed in the healthy controls. Importantly however, these differences between graph-theoretic metrics were partially reversed in delta and theta band networks, which were also significantly more similar to each other in patients than controls. Going further, we found that metrics of alpha network efficiency also correlated with the degree of behavioural awareness. Intriguingly, some patients in behaviourally unresponsive vegetative states who demonstrated evidence of covert awareness with functional neuroimaging stood out from this trend: they had alpha networks that were remarkably well preserved and similar to those observed in the controls. Taken together, our findings inform current understanding of disorders of consciousness by highlighting the distinctive brain networks that characterise them. In the significant minority of vegetative patients who follow commands in neuroimaging tests, they point to putative network mechanisms that could support cognitive function and consciousness despite profound behavioural impairment.
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From decisions to disorders: how neuroscience is changing what we know about ourselves

From decisions to disorders: how neuroscience is changing what we know about ourselves | Social Foraging | Scoop.it

People have wanted to understand our motivations, thoughts and behaviors since the ancient Greeks inscribed “know thyself” on the Temple of Apollo at Delphi. And understanding the brain’s place in health and disease is one of this century’s greatest challenges – take Alzheimer’s, dementia and depression for example.


There are many exciting contributions from neuroscience that have given insight into our thoughts and actions. Three neuroscientists have just been awarded the 2014 Nobel Prize for their discoveries of cells that act as a positioning system in the brain – in other words, the mechanism that allows us to navigate spaces using spatial information and memory at a cellular level.


There are many exciting contributions from neuroscience that have given insight into our thoughts and actions. For example, the neural basis of how we make fast and slow decisions and decision-making under conditions of uncertainty. There is also an understanding how the brain is affected by stress and how these stresses might switch our brains into habit mode, for example operating on “automatic pilot” and forgetting to carry out planned tasks, or the opposite goal-directed system, which would see you going out of your usual routine, for example, popping into a different supermarket to get special ingredients for a recipe.


Disruption in the balance between the two is evident in neuro-psychiatric disorders, such as obsessive compulsive disorder, and recent evidence suggests that lower grey matter volumes in the brain can bias towards habit formation. Neuroscience is also demonstrating commonalities in disorders of compulsivity, methamphetamine abuse and obese subjects with eating disorders.


Neuroscience can challenge previously accepted views. For example, major abnormalities in dopamine function were thought the main cause of adult attention deficit hyperactivity disorder (ADHD). However, recent work suggests that the main cause of the disorder may instead be associated with structural differences in grey matter in the brain.


What neuroscience has made evidently clear is that changes in the brain cause changes in your thinking and actions, but the relationship is two-way. Environmental stressors, including psychological and substance abuse, can also change the brain. We also now know our brains continue developing into late adolescence or early young adulthood, it is not surprising that these environmental influences are particularly potent in a number of disorders during childhood and adolescence including autism.



Via Dr. Stefan Gruenwald
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Who Needs a Driver? These Navy Boats Are Programmed to Swarm Like Bees

Who Needs a Driver? These Navy Boats Are Programmed to Swarm Like Bees | Social Foraging | Scoop.it

Using algorithms based on the swarming behavior of ants and bees, the U.S. Navy is turning to driverless boats to protect its ships.

 

This August, on the James River in Virginia, the U.S. Navy staged the kind of scene you’d expect to see at the beginning of a James Bond movie. As a large ship moved through the water, a helicopter overhead spotted an unidentified boat approaching and sent a warning to a small fleet of escort boats. Some were armed with loudspeakers, others with flashing lights, another with a .50 caliber machine gun.  

 

Once the fleet zeroed in on the threatening vessel with radar and infrared sensors, some of the escort boats broke away and quickly encircled it. They flashed lights and blasted warnings through loudspeakers. Threat resolved.

All of the escort boats were unmanned—and yet they moved together as a group, thanks to what’s known as “swarm intelligence.”

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Google, Facebook and Coca-Cola unite for digital sustainability platform Collectively

Google, Facebook and Coca-Cola unite for digital sustainability platform Collectively | Social Foraging | Scoop.it
The digital platform, which launches today, is a website that "celebrates" and "connects" cutting-edge ideas that are shaping the future sustainably. It aims to "inspire" and accelerate sustainable living by showcasing the work individuals and organisations are doing to operate in a more sustainable way. It will also promote initiatives of the brands involved.

On its home page, Collectively says it has launched because: "Today's media is obsessed with fear-mongering tactics, and a pervasive pessimism that would have us all believing that 'everything is f*cked, and it's all our fault,' which has had the undesirable effect of making people feel alienated and ineffectual, unable to figure out what they can do to alter the current path we're on."

There are 29 companies signed up to the project including BT, Carlsberg, Diageo, McDonalds, Microsoft, Nestlé, Nike, PepsiCo, The Dow Chemical Company and Twitter.
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A Man Took This Photograph Of Birds, And Turned Their Positions Into Musical Notes

A Man Took This Photograph Of Birds, And Turned Their Positions Into Musical Notes | Social Foraging | Scoop.it
What would happen if birds perched on electrical wires were transformed into musical notes? How would their position in space translate sonically? Those were exactly the questions Jarbas Agnelli asked one day. “I saw this picture of birds on the electric wires,” said Jarbas Agnelli. “I cut out the photo and decided to make a song, using the exact location of the birds as notes. I was just curious to hear what melody the birds were creating." Watch the final result here.  
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The Evolutionary Mystery of Left-Handedness and What It Reveals About How the Brain Works

The Evolutionary Mystery of Left-Handedness and What It Reveals About How the Brain Works | Social Foraging | Scoop.it

From Medieval sword-fighters to Broca’s brains, or why the hand may hold the key to the link between creativity and mental illness.

 

“Sahara is too little price / to pay for thy Right hand,” Emily Dickinson wrote in a poem. “The right hand = the hand that is aggressive, the hand that masturbates,” Susan Sontag pondered in her diary in 1964. “Therefore, to prefer the left hand! … To romanticize it, to sentimentalize it!” The human hand has long carried cultural baggage, and yet we still struggle to unclutch from it the myths and reveal the realities.

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Cities as complex adaptative systems. Luis Bettencourt

http://youtu.be/vp6eKjQHNl0

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Office Networks Reveal Which Co-Workers To Avoid During Infectious Outbreaks

Office Networks Reveal Which Co-Workers To Avoid During Infectious Outbreaks | Social Foraging | Scoop.it
The way disease spreads through society is currently the subject of significant interest, not least because of the recent, frightening outbreaks of ebola and various strains of bird flu. One hope is that a better understanding of this process can lead to more efficient and cost-effective methods of vaccination.

Last week, we looked at just such a study of interpersonal contacts within schools. This suggested that an effective way to prevent an epidemic would be to close a single class rather than the entire school.

Today, Mathieu Genois at the University of Toulon in France and a few pals study the pattern of face-to-face contacts in an office building and say that this too suggests a novel and cost-effective vaccination strategy for preventing epidemics.

The team studied the face-to-face interactions over two weeks between people working in an office building belonging to the French Institute for Public Health Surveillance (the InVS) near Paris. The building hosts three different scientific departments along with a human resources fepartment and a logistics department.

Workers within the building were given wearable sensors that detect the close proximity of others nearby. Since the body acts as a shield at the radio frequencies used by the sensors, the devices only detect contacts when people face each other at distances of less than 150 centimetres. In total, the team distributed 100 of these sensors to the two thirds of the staff who agreed to take part.
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Scientists make droplets move on their own: Drops of alcohol that can find their way through a maze

Droplets are simple spheres of fluid, not normally considered capable of doing anything on their own. But now researchers have made droplets of alcohol move through water. In the future, such moving droplets may deliver medicines, etc. To be able to move on your own – to be self-moving – is a feature normally seen in living organisms. But also non-living entities can be self-moving, report researchers from University of Southern Denmark and Institute of Chemical Technology in Prague, Czech Republic.
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Qualcomm Says Future Smartphones Will Have Built-In AI for Understanding Images and Faces

Qualcomm Says Future Smartphones Will Have Built-In AI for Understanding Images and Faces | Social Foraging | Scoop.it
Future smartphones will be able to understand what you’re taking photos of and recognize faces, says mobile chip maker Qualcomm. Researchers at the company are working to make a powerful new approach to artificial intelligence known as deep learning a standard feature of mobile devices.

Smartphone camera apps often have “scene” modes to get the best shots of landscapes, sports, or sunsets. Qualcomm has created a camera app able to identify different types of scenes on its own, based on their visual characteristics. That could lead to phones that can choose their own settings without having to send or receive data over the Internet.

Charles Bergan, who leads software research at Qualcomm, demonstrated that software in a sponsored talk at MIT Technology Review’s EmTech conference last week in Cambridge, Massachusetts. He said that it should be possible to use the same approach to create software that could decide the best moment to take a photo. “Maybe it will detect that it’s a soccer game and look for that moment when the ball is just lifting off,” he said.
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Exact solution for a metapopulation version of Schelling’s model

Exact solution for a metapopulation version of Schelling’s model | Social Foraging | Scoop.it
More than 40 y ago, Schelling introduced one of the first agent-based models in the social sciences. The model showed that even if people only have a mild preference for living with neighbors of the same color, complete segregation will occur. This model has been much discussed by social scientists and analyzed by physicists using analogies with spin-1 Ising models and other systems. Here, we study the metapopulation version of the model, which mimics the division of a city into neighborhoods, and we present the first analysis to our knowledge that gives detailed information about the structure of equilibria and explicit formulas for their densities.
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Arsenal’s ‘secret’ signing: club buys £2m revolutionary data company

Arsenal’s ‘secret’ signing: club buys £2m revolutionary data company | Social Foraging | Scoop.it
US-based data company StatDNA provides expert analysis guiding everything from identifying new players to post-game tactical analysis

 

At the top of the agenda, as usual, was the subject of new signings. Why, the Arsenal shareholders wanted to know at Thursday’s AGM, had the club failed in the summer to sign the extra defender they so plainly needed? The numbers appeared simple enough. Arsène Wenger’s squad has five senior defenders while the club has £207.9m in the bank.

 

Ivan Gazidis, the club’s chief executive, did his best to explain that the vast majority of the headline cash figure was already accounted for, but down on the floor there was scepticism. He had a seven-figure signing he did want to promote. It is one that strikes a fundamental chord with him and the Arsenal majority shareholder, Stan Kroenke, even if there continues to be a hush-hush quality that underpins it.

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Site-specific group selection drives locally adapted group compositions

Group selection may be defined as selection caused by the differential extinction or proliferation of groups. The socially polymorphic spider Anelosimus studiosus exhibits a behavioural polymorphism in which females exhibit either a ‘docile’ or ‘aggressive’ behavioural phenotype. Natural colonies are composed of a mixture of related docile and aggressive individuals, and populations differ in colonies’ characteristic docile:aggressive ratios. Using experimentally constructed colonies of known composition, here we demonstrate that population-level divergence in docile:aggressive ratios is driven by site-specific selection at the group level—certain ratios yield high survivorship at some sites but not others. Our data also indicate that colonies responded to the risk of extinction: perturbed colonies tended to adjust their composition over two generations to match the ratio characteristic of their native site, thus promoting their long-term survival in their natal habitat. However, colonies of displaced individuals continued to shift their compositions towards mixtures that would have promoted their survival had they remained at their home sites, regardless of their contemporary environment. Thus, the regulatory mechanisms that colonies use to adjust their composition appear to be locally adapted. Our data provide experimental evidence of group selection driving collective traits in wild populations.

 

Site-specific group selection drives locally adapted group compositions
• Jonathan N. Pruitt & Charles J. Goodnight

Nature 514, 359–362 (16 October 2014) http://dx.doi.org/10.1038/nature1381


Via Complexity Digest
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Arjen ten Have's curator insight, October 17, 7:49 AM

Now the really interesting part would be of course to explain this emergent groups selection by gene selection. How do we define or, if you wish, describe the Evolutionary Stable Strategy that is behind this interesting phenomenon. What can we as human society learn from this?

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Cell memory and adaptation in chemotaxis

Cell memory and adaptation in chemotaxis | Social Foraging | Scoop.it
How cells direct motion in response to environmental stimuli has long fascinated biologists. Chemotaxis, the migration guided by chemical gradients, is a fundamental property of many cells and plays important roles in physiology and pathological conditions. One of the best-studied models for chemotaxis is the social amoeba Dictyostelium discoideum. In nutrient-deprived environments, Dictyostelium cells initiate a developmental program that allows them to aggregate and form fruiting bodies. During this process, cells periodically secrete cAMP, which functions as a chemoattractant to guide their migration. In a field of cells, periodic waves of cAMP are initiated from an aggregation center every ∼6 min and sweep out in concentric circles or spirals. As the waves approach cells, they first experience a spatial gradient, with the high side facing the center. Thereafter, because the spatial profile of the waves is symmetric (1), as the peak of the wave passes cells are faced with an equivalent but oppositely directed gradient (Fig. 1). Despite this change of direction, the overall movement of cells is toward the center. How chemotactic cells are able to sense the approaching wave but appear to ignore it as it moves away is known as the “back of the wave” problem, and has perplexed the field for some time. Two possible explanations have been proposed. The first explanation relies on the fact that cells adapt—or cease to respond—to constant levels of stimuli (2). Therefore, cells are more sensitive during the rising phase of the wave, when the concentration of the chemoattractant is increasing over time, and lose sensitivity at the back of the wave when the concentration is declining. The second explanation notes that over time cells develop an intrinsic polarity with well-defined anterior and posterior regions, and this polarity allows cells to maintain their direction when the guidance cue fluctuates (3). The relative importance of each process in allowing cells to move unidirectionally in periodic waves has not been known, although both suggest that in addition to the spatial profile, cells make use of the temporal information of the concentration. In PNAS, Skoge et al. address this question through careful analysis of migration and the corresponding signaling activities of cells responding to spatiotemporal patterns of cAMP generated by a novel microfluidic device (4). The authors show that cells display a memory that persists beyond—but is modulated by—the adaptation process. This interplay between memory and adaptation allows cells to move against the gradient in the back of the wave.
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A Stochastic Process Approach to Model Distributed Computing on Complex Networks

In this work we present analytic expressions for the expected values of the performance metrics of parallel applications when the distributed computing infrastructure has a complex topology. Through active probing tests we analyse the structure of a real distributed computing environment. From the resulting network we both validate the analytic expressions and explore the performance metrics under different conditions through Monte Carlo simulations. In particular we gauge computing paradigms with different hierarchical structures in computing services. Fully decentralised (i.e., peer-to-peer) environments provide the best performance. Moreover, we show that it is possible to improve significantly the parallel efficiency by implementing more intelligent configurations of computing services and task allocation strategies (e.g., by using a betweenness centrality measure). We qualitatively reproduce results of previous works and provide closed-form solutions that link topology, application’s structure and allocation parameters when job dependencies and a complex network structure are considered.

 

Distributed Computing on Complex Networks
Francisco Prieto-Castrillo, Antonio Astillero, María Botón-Fernández

http://link.springer.com/article/10.1007/s10723-014-9317-4


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Computational Biology and Data Science at the New York Times

Nearly all fields have been or are being transformed by the availability of copious data and the tools to learn from them. Dr. Chris Wiggins (Chief Data Scientist, New York Times) will talk about using machine learning and large data in both academia and in business. He shares some ways re-framing domain questions as machine learning tasks has opened up new avenues for understanding both in academic research and in real-world applications.
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Wearables, robotics and cognitive computing are the future for Tesco

Wearables, robotics and cognitive computing are the future for Tesco | Social Foraging | Scoop.it
In the next five years, robotics, wearable technology and cognitive computing will start to be commonplace in retail, according to Tesco.
Speaking at the IGD Convention, Mike McNamara, chief information officer at Tesco, said disruptive technologies would become a part of the way that retailers operate, not within 20 years, but in the next five.

"We’ve only scratched the surface, we’re only just in the foothills of how we exploit technology. In this multichannel age the customer is in charge of the shopping process. The challenge for us is to help out business to make the most of tech."

He added that the demands of customers to "get what I want" and not queue, for example, translate well in the digital world where customers have the "internet in the palm of their hands" and are "in charge of the shopping process".

As a result, the industry needs to do more to innovate, harness and exploit the capability of disruptive technologies that could improve customer experience online and in store. 

"Tech gives us the opportunity to serve our customers even better," he said, adding that some colleagues were "trialling the latest smartwatch technology for stock control".
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Impact of heterogeneity and socioeconomic factors on individual behavior in decentralized sharing ecosystems

Impact of heterogeneity and socioeconomic factors on individual behavior in decentralized sharing ecosystems | Social Foraging | Scoop.it
Tens of millions of individuals around the world use decentralized content distribution systems, a fact of growing social, economic, and technological importance. These sharing systems are poorly understood because, unlike in other technosocial systems, it is difficult to gather large-scale data about user behavior. Here, we investigate user activity patterns and the socioeconomic factors that could explain the behavior. Our analysis reveals that (i) the ecosystem is heterogeneous at several levels: content types are heterogeneous, users specialize in a few content types, and countries are heterogeneous in user profiles; and (ii) there is a strong correlation between socioeconomic indicators of a country and users behavior. Our findings open a research area on the dynamics of decentralized sharing ecosystems and the socioeconomic factors affecting them, and may have implications for the design of algorithms and for policymaking.
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Confidence Sharing: An Economic Strategy for Efficient Information Flows in Animal Groups

Confidence Sharing: An Economic Strategy for Efficient Information Flows in Animal Groups | Social Foraging | Scoop.it
Social animals may share information to obtain a more complete and accurate picture of their surroundings. However, physical constraints on communication limit the flow of information between interacting individuals in a way that can cause an accumulation of errors and deteriorated collective behaviors. Here, we theoretically study a general model of information sharing within animal groups. We take an algorithmic perspective to identify efficient communication schemes that are, nevertheless, economic in terms of communication, memory and individual internal computation. We present a simple and natural algorithm in which each agent compresses all information it has gathered into a single parameter that represents its confidence in its behavior. Confidence is communicated between agents by means of active signaling. We motivate this model by novel and existing empirical evidences for confidence sharing in animal groups. We rigorously show that this algorithm competes extremely well with the best possible algorithm that operates without any computational constraints. We also show that this algorithm is minimal, in the sense that further reduction in communication may significantly reduce performances. Our proofs rely on the Cramér-Rao bound and on our definition of a Fisher Channel Capacity. We use these concepts to quantify information flows within the group which are then used to obtain lower bounds on collective performance. The abstract nature of our model makes it rigorously solvable and its conclusions highly general. Indeed, our results suggest confidence sharing as a central notion in the context of animal communication.
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Researcher Finds Support For One Of Darwin's Controversial Theories (Jump Dispersal)

Researcher Finds Support For One Of Darwin's Controversial Theories (Jump Dispersal) | Social Foraging | Scoop.it
When Charles Darwin first put forward his revolutionary theory of evolution, he was met with considerable opposition and skepticism from both scientific and religious circles. While this is now entirely accepted by the scientific community, some of his ideas have continued to cause controversy for more than 150 years. One contentious hypothesis, for example, suggested that organisms could cross vast distances and oceans and then successfully establish themselves in a new geographic location.

To achieve this “jump dispersal,” it was proposed that organisms could hitch a ride on various objects such as mats of vegetation and icebergs, or even just blow in the wind. Although this idea has been largely dismissed by the scientific community, new research on island dwelling organisms suggests that he may have been right after all. Using statistical modeling to compare Darwin’s theory with a competing theory, strong evidence in support of jump dispersal was found.  The work has been published in Systematic Biology.

Attempting to explain how certain species ended up in particular geographical locations across the globe becomes tricky when close relatives live on different continents, separated by vast oceans. Darwin thought that some organisms might have piggybacked to get to their destinations, but opponents thought that the idea of lizards floating on bits of wood for thousands of miles was a bit too far-fetched. Instead, it was suggested that organisms must have crossed “land bridges” to colonize new areas before the continents split apart. This “vicariance” theory was well-received by scientists, so much so that models used to estimate the biogeographic history of certain species completely excluded jump dispersal.

However, there are several lines of evidence to suggest that vicariance does not always cut the mustard. For example, some species’ ancestors are thought to have evolved millions of years after the continents separated, meaning that confidence in this theory has gradually waned over time. Because of this, the National Institute for Mathematical and Biological Synthesis researcher Nicholas Matzke took it upon himself to design a computer program to compare these two contrasting theories. 
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The Neural Basis of Mark Making: A Functional MRI Study of Drawing

The Neural Basis of Mark Making: A Functional MRI Study of Drawing | Social Foraging | Scoop.it
Compared to most other forms of visually-guided motor activity, drawing is unique in that it “leaves a trail behind” in the form of the emanating image. We took advantage of an MRI-compatible drawing tablet in order to examine both the motor production and perceptual emanation of images. Subjects participated in a series of mark making tasks in which they were cued to draw geometric patterns on the tablet's surface. The critical comparison was between when visual feedback was displayed (image generation) versus when it was not (no image generation). This contrast revealed an occipito-parietal stream involved in motion-based perception of the emerging image, including areas V5/MT+, LO, V3A, and the posterior part of the intraparietal sulcus. Interestingly, when subjects passively viewed animations of visual patterns emerging on the projected surface, all of the sensorimotor network involved in drawing was strongly activated, with the exception of the primary motor cortex. These results argue that the origin of the human capacity to draw and write involves not only motor skills for tool use but also motor-sensory links between drawing movements and the visual images that emanate from them in real time.
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Social Network Analysis Shows Direct Evidence for Social Transmission of Tool Use in Wild Chimpanzees

Social Network Analysis Shows Direct Evidence for Social Transmission of Tool Use in Wild Chimpanzees | Social Foraging | Scoop.it

Social network analysis methods have made it possible to test whether novel behaviors in animals spread through individual or social learning. To date, however, social network analysis of wild populations has been limited to static models that cannot precisely reflect the dynamics of learning, for instance, the impact of multiple observations across time. Here, we present a novel dynamic version of network analysis that is capable of capturing temporal aspects of acquisition—that is, how successive observations by an individual influence its acquisition of the novel behavior. We apply this model to studying the spread of two novel tool-use variants, “moss-sponging” and “leaf-sponge re-use,” in the Sonso chimpanzee community of Budongo Forest, Uganda. Chimpanzees are widely considered the most “cultural” of all animal species, with 39 behaviors suspected as socially acquired, most of them in the domain of tool-use. The cultural hypothesis is supported by experimental data from captive chimpanzees and a range of observational data. However, for wild groups, there is still no direct experimental evidence for social learning, nor has there been any direct observation of social diffusion of behavioral innovations. Here, we tested both a static and a dynamic network model and found strong evidence that diffusion patterns of moss-sponging, but not leaf-sponge re-use, were significantly better explained by social than individual learning. The most conservative estimate of social transmission accounted for 85% of observed events, with an estimated 15-fold increase in learning rate for each time a novice observed an informed individual moss-sponging. We conclude that group-specific behavioral variants in wild chimpanzees can be socially learned, adding to the evidence that this prerequisite for culture originated in a common ancestor of great apes and humans, long before the advent of modern humans.

 
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Workshop on Neural Information Dynamics, Causality and Computation near Criticality

LOEWE-NeFF and the Frankfurt Institute for Advanced Studies (FIAS) jointly invite you to a “Workshop on Neural Information Dynamics, Causality and Computation near Criticality” December 12-13th, 2014

The workshop is preceded by a “Software course on Neural Information Dynamics with TRENTOOL, the Java Information Dynamics Toolkit and MuTE” December 10-11th, 2014.

 

Venue: Workshop and student course will be held at the Frankfurt Institute for Advanced Studies (FIAS, www.fias.uni-frankfurt.de), Ruth-Moufang-Straße 1, 60438 Frankfurt, Germany.


The workshop addresses the analysis of neural computation in large neural systems and covers three tightly related topics in the field of modern analysis of neural data:

- Causality

- Neural information dynamics

- Large scale organisation and criticality

 

The supporting software course addresses young scientists who intend to apply information theoretic measures for neuroscience hands on, and that would like to contribute code to one of the open source toolboxes on the topic.

Apply/register before October 24th


Via Complexity Digest
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