Abstract: In the run-up to the recent financial crisis, an increasingly elaborate set of financial instruments emerged, intended to optimize returns to individual institutions with seemingly minimal risk. Essentially no attention was given to their possible effects on the stability of the system as a whole. Drawing analogies with the dynamics of ecological food webs and with networks within which infectious diseases spread, we explore the interplay between complexity and stability in deliberately simplified models of financial networks. We suggest some policy lessons that can be drawn from such models, with the explicit aim of minimizing systemic risk.
The Newest Synthesis: Understanding the Interplay of Evolutionary and Ecological Dynamics, Science
Excerpt: The effect of ecological change on evolution has long been a focus of scientific research. The reverse‚Ä"how evolutionary dynamics affect ecological traits‚Ä"has only recently captured our attention, however, with the realization that evolution can occur over ecological time scales. This newly highlighted causal direction and the implied feedback loop‚Ä"eco-evolutionary dynamics‚Ä"is invigorating both ecologists and evolutionists and blurring the distinction between them.
Excerpt: (...) swarm intelligence occurs when two or more individuals independently, or at least partly independently, acquire information that is processed through social interactions and is used to solve a cognitive problem in a way that would be impossible for isolated individuals. We propose at least one example of swarm intelligence in plants: coordination of individual roots in complex root systems.
Excerpt: Here we show that the social amoeba Dictyostelium discoideum has a primitive farming symbiosis that includes dispersal and prudent harvesting of the crop. About one-third of wild-collected clones engage in husbandry of bacteria. Instead of consuming all bacteria in their patch, they stop feeding early and incorporate bacteria into their fruiting bodies. They then carry bacteria during spore dispersal and can seed a new food crop, which is a major advantage if edible bacteria are lacking at the new site.
Nutritional state and collective motion: from individuals to mass migration, Proc. R. Soc. B
Excerpt: In order to move effectively in unpredictable or heterogeneous environments animals must make appropriate decisions in response to internal and external cues. Identifying the link between these components remains a challenge for movement ecology and is important in understanding the mechanisms driving both individual and collective motion. One accessible way of examining how internal state influences an individual's motion is to consider the nutritional state of an animal. Our experimental results reveal that nutritional state exerts a relatively minor influence on the motion of isolated individuals, but large group-level differences emerge from diet affecting inter-individual interactions.
Excerpt: The nature of distributed computation in complex systems has often been described in terms of the component operations of universal computation: information storage, trans- fer and modification. This thesis makes the original contribution of a complete framework to quantify each of these individual operations on information on a local scale in space and time within a system. We call this the study of information dynamics.
About this talk: Days before this talk, journalist Naomi Klein was on a boat in the Gulf of Mexico, looking at the catastrophic results of BP's risky pursuit of oil. Our societies have become addicted to extreme risk in finding new energy, new financial instruments and more ... and too often, we're left to clean up a mess afterward. Klein's question: What's the backup plan?
Evolutionary Mechanics: new engineering principles for the emergence of flexibility in a dynamic and uncertain world, arXiv
Excerpt: Engineered systems are designed to deftly operate under predetermined conditions yet are notoriously fragile when unexpected perturbations arise. In contrast, biological systems operate in a highly flexible manner; learn quickly adequate responses to novel conditions, and evolve new routines/traits to remain competitive under persistent environmental change. A recent theory on the origins of biological flexibility has proposed that degeneracy - the existence of multi-functional components with partially overlapping functions - is a primary determinant of the robustness and adaptability found in evolved systems. While degeneracy's contribution to biological flexibility is well documented, there has been little investigation of degeneracy design principles for achieving flexibility in systems engineering.
Excerpt: Now it seems the immune system, and infections that stimulate it, can influence our moods, memory and ability to learn. Some strange behaviours, such as obsessive compulsive disorder, may be triggered by infections, and the immune system may even shape our basic personalities, such as how anxious or impulsive we are.
Morphological change in machines accelerates the evolution of robust behavior, PNAS
Excerpt: Most animals exhibit significant neurological and morphological change throughout their lifetime. No robots to date, however, grow new morphological structure while behaving. This is due to technological limitations but also because it is unclear that morphological change provides a benefit to the acquisition of robust behavior in machines. Here I show that in evolving populations of simulated robots, if robots grow from anguilliform into legged robots during their lifetime in the early stages of evolution, and the anguilliform body plan is gradually lost during later stages of evolution, gaits are evolved for the final, legged form of the robot more rapidly‚Ä"and the evolved gaits are more robust‚Ä"compared to evolving populations of legged robots that do not transition through the anguilliform body plan.
Complexity through Recombination: From Chemistry to Biology, Entropy
Abstract: Recombination is a common event in nature, with examples in physics, chemistry, and biology. This process is characterized by the spontaneous reorganization of structural units to form new entities. Upon reorganization, the complexity of the overall system can change. In particular the components of the system can now experience a new response to externally applied selection criteria, such that the evolutionary trajectory of the system is altered. The link between chemical and biological forms of recombination is explored. (...) The results underscore the importance of recombination in the origins of life on the Earth and its subsequent evolutionary divergence.
Gross Domestic Happiness: What Is the Relationship between Money and Well-being?, Knowledge@Wharton
Summary: What exactly is the relationship between money and happiness? It's a difficult question to pin down, experts say. While more money may make us happier, other considerations -- such as whether you live in an economically advanced country and how you think about your time -- also play into the equation. An increasing number of economists, sociologists and psychologists are now working in the field, and most agree that there is a strong link between a country's level of economic development and the happiness of its people.
The Functional Consequences of Mutualistic Network Architecture, PLoS ONE
Excerpt: The architecture and properties of many complex networks play a significant role in the functioning of the systems they describe. Recently, complex network theory has been applied to ecological entities, like food webs or mutualistic plant-animal interactions [...] We found a consistent relationship between the topology of the networks and their functioning, since variation across populations in the average per-capita production of juvenile plants was positively and significantly related with network nestedness, connectivity and clustering.
Larval Connectivity in an Effective Network of Marine Protected Areas, PLoS ONE
Excerpt: Acceptance of marine protected areas (MPAs) as fishery and conservation tools has been hampered by lack of direct evidence that MPAs successfully seed unprotected areas with larvae of targeted species. For the first time, we present direct evidence of large-scale population connectivity within an existing and effective network of MPAs.
Excerpt: Infanticide by newly immigrated or newly dominant males is reported among a variety of taxa, such as birds, rodents, carnivores and primates. Here we present a game theoretical model to explain the presence and prevalence of infanticide in primate groups. We have formulated a three-player game involving two males and one female and show that the strategies of infanticide on the males' part and polyandrous mating on the females' part emerge as Nash equilibria that are stable under certain conditions [...] These conclusions are confirmed by observations in the wild. These conclusions are confirmed by observations in the wild.
Modelling The Evolution And Diversity Of Cumulative Culture, Phil. Trans. B
Excerpt: Previous work on mathematical models of cultural evolution has mainly focused on the diffusion of simple cultural elements. However, a characteristic feature of human cultural evolution is the seemingly limitless appearance of new and increasingly complex cultural elements. Here, we develop a general modelling framework to study such cumulative processes, in which we assume that the appearance and disappearance of cultural elements are stochastic events that depend on the current state of culture. Five scenarios are explored: evolution of independent cultural elements, stepwise modification of elements, differentiation or combination of elements and systems of cultural elements. (ÔŅĹ)
abstract: We study the coevolution of networks and action choices in a Prisoners' Dilemma. Agents in our model learn about both action choices and choices of interaction partners (links) by imitating successful behavior of others. The resulting dynamics yields outcomes where both cooperators and defectors coexist under a wide range of parameters. Two scenarios can arise. Either there is ‚Äúfull separation‚ÄĚ of defectors and cooperators, i.e. they are found in two different, disconnected components. Or there is ‚Äúmarginalization‚ÄĚ of defectors, i.e. connected networks emerge with a center of cooperators and a periphery of defectors.
Abstract: More than half a century has now elapsed since coalition or alliance formation theory (CAFT) was first developed. During that time, researchers have amassed a vast amount of detailed and high-quality data on coalitions or alliances among primates and other animals. But models have not kept pace, and more relevant theory is needed. In particular, even though CAFT is primarily an exercise in polyadic game theory, game theorists have devoted relatively little attention to questions that motivate field research, and much remains largely unexplored. The state of the art is both a challenge and an opportunity. In this review we describe a variety of game-theoretic and related modelling approaches that have much untapped potential to address the questions that field biologists ask.
Excerpt: Punishment of non-cooperators has been observed to promote cooperation. Such punishment is an evolutionary puzzle because it is costly to the punisher while beneficial to others, for example, through increased social cohesion. Recent studies have concluded that punishing strategies usually pay less than some non-punishing strategies. These findings suggest that punishment could not have directly evolved to promote cooperation. However, while it is well established that reputation plays a key role in human cooperation, the simple threat from a reputation of being a punisher may not have been sufficiently explored yet in order to explain the evolution of costly punishment. Here, we first show analytically that punishment can lead to long-term benefits if ...
The effects of mental model formation on group decision making: An agent-based simulation, Complexity
Abstract: We investigated dynamics of group decision making on complex problems when agents can form mental models of others from discussion history. Results indicated that as the agents' memory capacity increases, the group reaches superficial consensus more easily. Surprisingly, however, the shared mental model of the problem develops only within a limited area of the problem space, because incorporating knowledge from others into one's own knowledge quickly creates local agreement on where relevant solutions are, leaving other potentially useful solutions beyond the scope of discussion. The mechanisms stifling group-level exploration and their implications for decision making research are discussed.
A mathematical theory of communication: Meaning, information, and topology, Complexity
Abstract: This article proposes a new mathematical theory of communication. The basic concepts of meaning and information are defined in terms of complex systems theory. Meaning of a message is defined as the attractor it generates in the receiving system; information is defined as the difference between a vector of expectation and one of perception. It can be sown that both concepts are determined by the topology of the receiving system.
New System for Analyzing Information on WikiLeaks, Social Media, ScienceDaily
Excerpts: (ÔŅĹ) has designed a system for exploring information on networks or graphs that can complement internet search engines and is of particular interest in areas related to social media, the internet, biomedicine, fraud detection, education and advanced bibliographic searches. (ÔŅĹ) the technology can be used to extract information from WikiLeaks from two perspectives: one, to obtain generic indicators that provide information on whether the data network has the features of a social network and whether communities of data are created that can provide relevant information; and two, to use the documents hosted on the website to analyze how a topic evolves over time, (ÔŅĹ).
Between Necessity and Probability: Searching for the Definition and Origin of Life, Springer
This book systematically explores the early origins and basic definition of life. It investigates the major theories of the origins of life in light of modern research with the aim of distinguishing between the necessary and the optional and between deterministic and random influences in the emergence of what we call ‚Äėlife‚Äô. It treats and views life as a cosmic phenomenon whose emergence and driving force should be viewed independently from its Earth-bound natural history and makes the argument that understanding life in its broadest context requires a material-independent perspective that identifies its essential fingerprints.
Complex Dynamics in Physiological Systems: From Heart to Brain, Springer
Nonlinear dynamics has become an important field of research in recent years in many areas of the natural sciences. In particular, it has potential applications in biology and medicine; nonlinear data analysis has helped to detect the progress of cardiac disease, physiological disorders, for example episodes of epilepsy, and others. This book focuses on the current trends of research concerning the prediction of sudden cardiac death and the onset of epileptic seizures, using the nonlinear analysis based on ECG and EEG data. Topics covered include the analysis of cardiac models and neural models. (...)
Introduction to Complexity and Complex Systems, CRC Press
The boundaries between simple and complicated, and complicated and complex system designations are fuzzy and debatable, even using quantitative measures of complexity. However, if you are a biomedical engineer, a biologist, physiologist, economist, politician, stock market speculator, or politician, you have encountered complex systems. Furthermore, your success depends on your ability to successfully interact with and manage a variety of complex systems. In order not to be blindsided by unexpected results, we need a systematic, comprehensive way of analyzing, modeling, and simulating complex systems to predict non-anticipated outcomes. (...)
Based on only elementary mathematics, this engaging account of chaos theory bridges the gap between introductions for the layman and college-level texts. It develops the science of dynamics in terms of small time steps, describes the phenomenon of chaos through simple examples, and concludes with a close look at a homoclinic tangle, the mathematical monster at the heart of chaos. The presentation is enhanced by many figures, animations of chaotic motion (available on a companion CD), and biographical sketches of the pioneers of dynamics and chaos theory. (...)
Over the last decade, the study of complex networks has expanded across diverse scientific fields. Increasingly, science is concerned with the structure, behavior, and evolution of complex systems ranging from cells to ecosystems. Modern network approaches are beginning to reveal fundamental principles of brain architecture and function, and in this book, Olaf Sporns describes how the integrative nature of brain function can be illuminated from a complex network perspective. Highlighting the many emerging points of contact between neuroscience and network science, the book serves to introduce network theory to neuroscientists and neuroscience to those working on theoretical network models. (...)
Sleights of Mind: What the Neuroscience of Magic Reveals about Our Everyday Deceptions, Henry Holt and Co.
The authors, the founders of the exciting new discipline of neuromagic, have convinced some of the world's greatest magicians to allow scientists to study their techniques for tricking the brain. This book is the result of the authors' yearlong, world-wide exploration of magic and how its principles apply to our behavior. Magic tricks fool us because humans have hardwired processes of attention and awareness that are hackable: a good magician uses your mind's own intrinsic properties against you in a form of mental jujitsu. Now magic can reveal how our brains work in everyday situations. (...)
ASSYSTComplexity One of the main goals of the ASSYST Coordination Action is to promote Complex Systems for Socially Intelligent ICT (COSI-ICT) and, more generally, Complex Systems (CS) Science in Europe and Worldwide. We do this by communicating widely with scientists, policy makers, and business people, and by showcasing success stories of CS applications.