Emergence: How Complex Wholes Emerge From Simple Parts
Throughout nature, throngs of relatively simple elements can self-organize into behaviors that seem unexpectedly complex. Scientists are beginning to understand why and how these phenomena emerge without a central organizing entity.
The Human Generosity Project is the first large-scale transdisciplinary research project to investigate the interrelationship between biological and cultural influences on human generosity. We use multiple methodologies to understand the nature and evolution of human generosity including fieldwork, laboratory experiments and computational modeling.
Neurosexism: the myth that men and women have different brains
[…] as The Gendered Brain reveals, conclusive findings about sex-linked brain differences have failed to materialize. Beyond the “missing five ounces” of female brain — gloated about since the nineteenth century — modern neuroscientists have identified no decisive, category-defining differences between the brains of men and women. In women’s brains, language-processing is not spread any more evenly across the hemispheres than it is in men’s, as a small 1995 Nature study proclaimed but a large 2008 meta-analysis disproved (B. A. Shaywitz et al. Nature 373, 607–609 (1995) and I. E. Sommer et al. Brain Res. 1206, 76–88; 2008). Brain size increases with body size, and certain features, such as the ratio of grey to white matter or the cross-sectional area of a nerve tract called the corpus callosum, scale slightly non-linearly with brain size. But these are differences in degree, not kind. As Rippon notes, they are also seen when we compare small-headed men to large-headed women, and have no relationship to differences in hobbies or take-home pay.
The Gendered Brain: The New Neuroscience That Shatters The Myth Of The Female Brain. Gina Rippon The Bodley Head (2019)
A Multilayer Structure Facilitates the Production of Antifragile Systems in Boolean Network Models
Antifragility is a property to not only resist stress and but also to benefit from it. Even though antifragile dynamics are found in various real-world complex systems where multiple subsystems interact with each other, the attribute has not been quantitatively explored yet in those complex systems which can be regarded as multilayer networks. Here we study how the multilayer structure affects the antifragility of the whole system. By comparing single-layer and multilayer Boolean networks based on our recently proposed antifragility measure, we found that the multilayer structure facilitated the production of antifragile systems. Our measure and findings can be utilized for many applications from understanding properties of biological systems with multilayer structures to designing more antifragile engineered systems.
A Multilayer Structure Facilitates the Production of Antifragile Systems in Boolean Network Models Hyobin Kim, Omar K. Pineda, Carlos Gershenson
Spatial Structure Can Decrease Symbiotic Cooperation
Mutualisms occur when at least two species provide a net fitness benefit to each other. These types of interactions are ubiquitous in nature, with more being discovered regularly. Mutualisms are vital to humankind: Pollinators and soil microbes are critical in agriculture, bacterial microbiomes regulate our health, and domesticated animals provide us with food and companionship. Many hypotheses exist on how mutualisms evolve; however, they are difficult to evaluate without bias, due to the fragile and idiosyncratic systems most often investigated. Instead, we have created an artificial life simulation, Symbulation, which we use to examine mutualism evolution based on (1) the probability of vertical transmission (symbiont being passed to offspring) and (2) the spatial structure of the environment. We found that spatial structure can lead to less mutualism at intermediate vertical transmission rates. We provide evidence that this effect is due to the ability of quasi species to purge parasites, reducing the diversity of available symbionts. Our simulation is easily extended to test many additional hypotheses about the evolution of mutualism and serves as a general model to quantitatively compare how different environments affect the evolution of mutualism.
Spatial Structure Can Decrease Symbiotic Cooperation Anya E. Vostinar and Charles Ofria
Controlling systemic risk – network structures that minimize it and node properties to calculate it
Evaluation of systemic risk in networks of financial institutions in general requires information of inter-institution financial exposures. In the framework of Debt Rank algorithm, we introduce an approximate method of systemic risk evaluation which requires only node properties, such as total assets and liabilities, as inputs. We demonstrate that this approximation captures a large portion of systemic risk measured by Debt Rank. Furthermore, using Monte Carlo simulations, we investigate network structures that can amplify systemic risk. Indeed, while no topology in general sense is a priori more stable if the market is liquid, a larger complexity is detrimental for the overall stability. Here we find that the measure of scalar assortativity correlates well with level of systemic risk. In particular, network structures with high systemic risk are scalar assortative, meaning that risky banks are mostly exposed to other risky banks. Network structures with low systemic risk are scalar disassortative, with interactions of risky banks with stable banks.
Controlling systemic risk – network structures that minimize it and node properties to calculate it Sebastian M. Krause, Hrvoje Štefančić, Vinko Zlatić, Guido Caldarelli
