Month: August 2020

On the problem of biological form

Marta Linde-Medina 
Theory in Biosciences volume 139, pages 299–308 (2020)

 

Embryonic development, which inspired the first theories of biological form, was eventually excluded from the conceptual framework of the Modern Synthesis as irrelevant. A major question during the last decades has centred on understanding whether new advances in developmental biology are compatible with the standard view or whether they compel a new theory. Here, I argue that the answer to this question depends on which concept of morphogenesis is held. Morphogenesis can be conceived as (1) a chemically driven or (2) a mechanically driven process. According to the first option, genetic regulatory networks drive morphogenesis. According to the second, morphogenesis results from an invariant tendency of embryonic tissues to restore changes in mechanical stress. While chemically driven morphogenesis allows an extension of the standard view, mechanically driven morphogenesis would deeply transform it. Which of these hypotheses has wider explanatory power is unknown. At present, the problem of biological form remains unsolved.

Source: link.springer.com

Why are U.S. Parties So Polarized? A “Satisficing” Dynamical Model

Why are U.S. Parties So Polarized? A "Satisficing" Dynamical Model
Vicky Chuqiao Yang, Daniel M. Abrams, Georgia Kernell, Adilson E. Motter

 

Since the 1960s, Democrats and Republicans in U.S. Congress have taken increasingly polarized positions, while the public’s policy positions have remained centrist and moderate. We explain this apparent contradiction by developing a dynamical model that predicts ideological positions of political parties. Our approach tackles the challenge of incorporating bounded rationality into mathematical models and integrates the empirical finding of satisficing decision making—voters settle for candidates who are "good enough" when deciding for whom to vote. We test the model using data from the U.S. Congress over the past 150 years, and find that our predictions are consistent with the two major political parties’ historical trajectory. In particular, the model explains how polarization between the Democrats and Republicans since the 1960s could be a consequence of increasing ideological homogeneity within the parties.

Source: arxiv.org

The Paradigm of Social Complexity: An Alternative Way of Understanding Societies and their Economies by Gonzalo Castañeda

With the recent developments in computing technologies and the thriving research scene in Complexity Science, economists and other social scientists have become aware of a more flexible and promising alternative for modelling socioeconomic systems; one that, in contrast with neoclassical economics, advocates for the realism of the assumptions, the importance of context and culture, the heterogeneity of agents (individuals or organisations), and the bounded rationality of individuals who behave and learn in multifaceted ways in uncertain environments. The book synthesises an extensive body of work in the field of social complexity and constructs a unifying framework that allows developing concrete applications to important socioeconomic problems. This one-of-a-kind textbook provides a comprehensive panorama for advanced undergraduates and graduate students who want to become familiar with a wide range of issues related to social complexity. It is also a pioneering text that can support professors who wish to learn techniques and produce research in this novel field.
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After reviewing the main concepts, premises and implications of complexity theory, the book frames this vision within the history of economic thought. Then, it articulates a meta-theory in which interdependent agents are embedded in a social context and whose collective and decentralised behaviour generates socio-economic phenomena. Such a framework builds on theories from evolutionary, institutional and behavioural economics, as well as analytical sociology. The book then reviews different computational tools for modelling complex adaptive systems, such as cellular automata, networks, and agent-based models. It elaborates on their analytical advantages in comparison to equation-based models, and how they can be calibrated/estimated and validated with empirical data. Finally, the book advocates for the practical use of these computational tools and makes a case for policy applications and the study of causal mechanisms.

Source: www.social-complexity.com

Apollo’s Arrow: The Profound and Enduring Impact of Coronavirus on the Way We Live

A piercing and scientifically grounded look at the emergence of the coronavirus pandemic and how it will change the way we live.
 
Apollo’s Arrow offers a riveting account of the impact of the coronavirus pandemic as it swept through American society in 2020, and of how the recovery will unfold in the coming years. Drawing on momentous (yet dimly remembered) historical epidemics, contemporary analyses, and cutting-edge research from a range of scientific disciplines, bestselling author, physician, sociologist, and public health expert Nicholas A. Christakis explores what it means to live in a time of plague — an experience that is paradoxically uncommon to the vast majority of humans who are alive, yet deeply fundamental to our species.

Unleashing new divisions in our society as well as opportunities for cooperation, this 21st-century pandemic has upended our lives in ways that will test, but not vanquish, our already frayed collective culture. Featuring new, provocative arguments and vivid examples ranging across medicine, history, sociology, epidemiology, data science, and genetics, Apollo’s Arrow envisions what happens when the great force of a deadly germ meets the enduring reality of our evolved social nature.

 

Source: www.amazon.com