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Punctuated Equilibrium (punctuated + equilibrium)
Selected AbstractsThe multiple directions of evolutionary changeBIOESSAYS, Issue 6 2008Diego Rasskin-Gutman The theory of Punctuated Equilibria challenges the neo-Darwinian tenet that evolution is a uniform process. Recently, an article by Hunt1 has found that directional change during the evolution of a lineage is relatively small (occurring only in 5% of 250 analyzed traits). Of those traits that were shown to follow a trend, size was more likely to show gradual changes, whereas shape changes were more random. Here, we provide a short view of the nature of evolutionary trends, showing that directional change within lineages and among clades provides valuable evolutionary information about the processes involved in their generation. BioEssays 30:521,525, 2008. © 2008 Wiley Periodicals, Inc. [source] Punctuated Equilibrium and Agenda-Setting: Bringing Parties Back in: Policy Change after the Dutroux Crisis in BelgiumGOVERNANCE, Issue 3 2008STEFAAN WALGRAVE The article analyzes how focusing events affect the public and political agenda and translate into policy change. Empirically, the study focuses on the policy changes initiated by paedophile Marc Dutroux's arrest in 1996 in Belgium. Theoretically, the article tests whether Baumgartner and Jones's (1993) U.S. punctuated equilibrium approach applies to a most different system case, Belgium being a consociational democracy and a partitocracy. Their approach turns out to be useful to explain this "critical case": Policy change happens when "policy images" and "policy venues" shift. Yet, the Dutroux case shows also that political parties, as key actors in the Belgian policy process, should be integrated more explicitly in the punctuated equilibrium theory. Finally, the article argues that the quantitative analysis of longitudinal data sets on several agendas should be supplemented with qualitative case study evidence (e.g., interviews with key decision makers) to unravel the complex case of issue attention and policy change. [source] Punctuated Equilibrium, Bureaucratization, and Budgetary Changes in SchoolsPOLICY STUDIES JOURNAL, Issue 1 2004Scott E. Robinson For half of a century, models of nonrational behavior have grown in popularity for explaining the behavior of administrative organizations. However, models of nonrational behavior are notoriously difficult to test because nonrational behavior is often difficult to separate from fully rational behavior. Recent research has suggested that particular types of nonrational processes should produce "punctuated" equilibria rather than "instantaneous" equilibria. In these nonrational processes, a decision maker underresponds to changes for a long period of time. Once pressure for change becomes overwhelming, the decision maker adopts a radical change. This is called "punctuation." The key to identifying this type of nonrationality of a process's rationality is the comparative success of fitting the observed behavior to "punctuated" rather than "instantaneous" equilibria. True, Jones, and Baumgartner (1999) developed a method for comparing the distribution of decision outputs as a strategy for assessing the relative degree of "punctuation" in the decision processes. By assessing the kurtosis (or "peakedness") of the distribution of decision outputs, one can get a sense of the excess (compared with a standard, normal distribution) of low and high rates of change,a sign of punctuated equilibrium. This article extends these recent developments by adapting the method to a comparative kurtosis framework. The results suggest that bureaucracy in K,12 schools serves to reduce (rather than amplify) the punctuations in budgeting processes. The article concludes with a discussion of the potential extension of the empirical results and modifications to the testing procedure. [source] Punctuated Equilibrium in Comparative PerspectiveAMERICAN JOURNAL OF POLITICAL SCIENCE, Issue 3 2009Frank R. Baumgartner We explore the impact of institutional design on the distribution of changes in outputs of governmental processes in the United States, Belgium, and Denmark. Using comprehensive indicators of governmental actions over several decades, we show that in each country the level of institutional friction increases as we look at processes further along the policy cycle. Assessing multiple policymaking institutions in each country allows us to control for the nature of the policy inputs, as all the institutions we consider cover the full range of social and political issues in the country. We find that all distributions exhibit high kurtosis values, significantly higher than the Normal distribution which would be expected if changes in government attention and activities were proportionate to changes in social inputs. Further, in each country, those institutions that impose higher decision-making costs show progressively higher kurtosis values. The results suggest general patterns that we hypothesize to be related to boundedly rational behavior in a complex social environment. [source] Anatomy of Organizational CrisesJOURNAL OF CONTINGENCIES AND CRISIS MANAGEMENT, Issue 3 2000Peter Hwang As the business environment gets more complex, the crises faced by management are more frequent and, potentially, more devastating. Previous research on crises looks at specific cases, typologies and definitions of crises. This paper argues that crises are better understood through the way they develop. Based on the theory of punctuated equilibria in biology, two types of crises are proposed: abrupt versus cumulative. An organizing framework based on a punctuated equilibria view of crisis is presented. In addition, the key concepts and mechanisms of the framework that provide management with a broadened view for coping with the ubiquitous nature of crises are discussed. [source] Punctuated Equilibrium, Bureaucratization, and Budgetary Changes in SchoolsPOLICY STUDIES JOURNAL, Issue 1 2004Scott E. Robinson For half of a century, models of nonrational behavior have grown in popularity for explaining the behavior of administrative organizations. However, models of nonrational behavior are notoriously difficult to test because nonrational behavior is often difficult to separate from fully rational behavior. Recent research has suggested that particular types of nonrational processes should produce "punctuated" equilibria rather than "instantaneous" equilibria. In these nonrational processes, a decision maker underresponds to changes for a long period of time. Once pressure for change becomes overwhelming, the decision maker adopts a radical change. This is called "punctuation." The key to identifying this type of nonrationality of a process's rationality is the comparative success of fitting the observed behavior to "punctuated" rather than "instantaneous" equilibria. True, Jones, and Baumgartner (1999) developed a method for comparing the distribution of decision outputs as a strategy for assessing the relative degree of "punctuation" in the decision processes. By assessing the kurtosis (or "peakedness") of the distribution of decision outputs, one can get a sense of the excess (compared with a standard, normal distribution) of low and high rates of change,a sign of punctuated equilibrium. This article extends these recent developments by adapting the method to a comparative kurtosis framework. The results suggest that bureaucracy in K,12 schools serves to reduce (rather than amplify) the punctuations in budgeting processes. The article concludes with a discussion of the potential extension of the empirical results and modifications to the testing procedure. [source] Transposable elements and an epigenetic basis for punctuated equilibriaBIOESSAYS, Issue 7 2009David W. Zeh Abstract Evolution is frequently concentrated in bursts of rapid morphological change and speciation followed by long-term stasis. We propose that this pattern of punctuated equilibria results from an evolutionary tug-of-war between host genomes and transposable elements (TEs) mediated through the epigenome. According to this hypothesis, epigenetic regulatory mechanisms (RNA interference, DNA methylation and histone modifications) maintain stasis by suppressing TE mobilization. However, physiological stress, induced by climate change or invasion of new habitats, disrupts epigenetic regulation and unleashes TEs. With their capacity to drive non-adaptive host evolution, mobilized TEs can restructure the genome and displace populations from adaptive peaks, thus providing an escape from stasis and generating genetic innovations required for rapid diversification. This "epi-transposon hypothesis" can not only explain macroevolutionary tempo and mode, but may also resolve other long-standing controversies, such as Wright's shifting balance theory, Mayr's peripheral isolates model, and McClintock's view of genome restructuring as an adaptive response to challenge. [source] GRADUAL VERSUS PUNCTUATED EQUILIBRIUM EVOLUTION IN THE TURKANA BASIN MOLLUSCS: EVOLUTIONARY EVENTS OR BIOLOGICAL INVASIONS?EVOLUTION, Issue 3 2008Bert Van Bocxlaer A running controversy in evolutionary thought was Eldredge and Gould's punctuated equilibrium model, which proposes long periods of morphological stasis interspersed with rapid bursts of dramatic evolutionary change. One of the earliest and most iconic pieces of research in support of punctuated equilibrium is the work of Williamson on the Plio-Pleistocene molluscs of the Turkana Basin. Williamson claimed to have found firm evidence for three episodes of rapid evolutionary change separated by long periods of stasis in a high-resolution sequence. Most of the discussions following this report centered on the topics of (eco)phenotypy versus genotypy and the possible presence of preservational and temporal artifacts. The debate proved inconclusive, leaving Williamson's reports as one of the empirical foundations of the paradigm of punctuated equilibrium. Here we conclusively show Williamson's original interpretations to be highly flawed. The supposed rapid bursts of punctuated evolutionary change represent artifacts resulting from the invasion of extrabasinal faunal elements in the Turkana palaeolakes during wet phases well known from elsewhere in Africa. [source] Knowledge strategy: Its relationship to environmental dynamism and complexity in product developmentKNOWLEDGE AND PROCESS MANAGEMENT: THE JOURNAL OF CORPORATE TRANSFORMATION, Issue 1 2010Elena Revilla Focusing on product development, this study extends the understanding of the environment-strategy framework and investigates the relative effect of two environmental variables, dynamism and complexity, on the product development knowledge strategy. Adopting a knowledge-based view, and assuming that the strategy's locus is knowledge creation (exploration) and knowledge application (exploitation), the study suggests that the development of a knowledge strategy is a managerial strategic choice that is related to the environment. The results of a survey on product development managers generally indicate that exploration and exploitation must be combined according to environmental factors by generating the alternative knowledge strategies of ambidexterity or punctuated equilibrium. Particularly, the study finds that in environments characterized by high levels of both dynamism and complexity product development efforts pursue and reinforce both explorative and exploitative activities through a knowledge strategy of ambidexterity. Though not perfectly supported, punctuated equilibrium seems to be a more plausible knowledge strategy in environmental contexts where either dynamism or complexity prevails. Copyright © 2010 John Wiley & Sons, Ltd. [source] Punctuated Equilibrium, Bureaucratization, and Budgetary Changes in SchoolsPOLICY STUDIES JOURNAL, Issue 1 2004Scott E. Robinson For half of a century, models of nonrational behavior have grown in popularity for explaining the behavior of administrative organizations. However, models of nonrational behavior are notoriously difficult to test because nonrational behavior is often difficult to separate from fully rational behavior. Recent research has suggested that particular types of nonrational processes should produce "punctuated" equilibria rather than "instantaneous" equilibria. In these nonrational processes, a decision maker underresponds to changes for a long period of time. Once pressure for change becomes overwhelming, the decision maker adopts a radical change. This is called "punctuation." The key to identifying this type of nonrationality of a process's rationality is the comparative success of fitting the observed behavior to "punctuated" rather than "instantaneous" equilibria. True, Jones, and Baumgartner (1999) developed a method for comparing the distribution of decision outputs as a strategy for assessing the relative degree of "punctuation" in the decision processes. By assessing the kurtosis (or "peakedness") of the distribution of decision outputs, one can get a sense of the excess (compared with a standard, normal distribution) of low and high rates of change,a sign of punctuated equilibrium. This article extends these recent developments by adapting the method to a comparative kurtosis framework. The results suggest that bureaucracy in K,12 schools serves to reduce (rather than amplify) the punctuations in budgeting processes. The article concludes with a discussion of the potential extension of the empirical results and modifications to the testing procedure. [source] Is There Life After Policy Streams, Advocacy Coalitions, and Punctuations: Using Evolutionary Theory to Explain Policy Change?POLICY STUDIES JOURNAL, Issue 4 2003Peter John This article reviews the current state of public policy theory to find out if researchers are ready to readdress the research agenda set by the classic works of Baumgartner and Jones (1993), Kingdon (1984) and Sabatier and Jenkins-Smith (1993). After reviewing the influences of institutional, rational choice, network, socio-economic and ideational approaches, the article pays tribute to the policy streams, punctuated equilibrium and policy advocacy coalition frameworks whilst also suggesting that future theory and research could identify more precisely the causal mechanisms driving policy change. The article argues that evolutionary theory may usefully uncover the micro-level processes at work, particularly as some the three frameworks refer to dymamic models and methods. After reviewing some evolutionary game theory and the study of memes, the article suggests that the benefits of evolutionary theory in extending policy theories need to be balanced by its limitations. [source] Reform, Reorganization, and the Renaissance of the Managerial Presidency: The Impact of 9/11 on the Executive EstablishmentPOLITICS & POLICY, Issue 2 2006Richard S. Conley In the wake of 9/11, realigning the human and financial resources of the executive branch to fight the war on terrorism quickly became the defining mission of George W. Bush's transformed presidency. This article assesses the ways in which 9/11 impacted on the executive branch of the U.S. government, using a framework of "punctuated equilibrium" to posit that the terrorist attacks on New York and Washington added considerable force to trends already in motion. September 11 proved a catalyst for significant institutional changes, such as the enhanced role of the vice president in policy making and the reorganization of the federal government and intelligence apparatus. Organizational reforms, driven in a top-down fashion by the White House, reflect President Bush's confidence in the managerial presidency: the notion that preventing future terror threats is effectively a problem of executive control, bureaucratic coordination, and adequate funding. [source] The Interpretive Process of Agenda-Building: A Research Design for Public PolicyPOLITICS & POLICY, Issue 1 2002Michael A. Smith A heuristic model is offered to guide empirical case studies into public policy change in a stable, pluralistic system. Empirical information, filtered to the policymakers and the public through a system of preexisting values, lies at the heart of policy change. The model integrates several strands of thought on policy, including: Baumgartner and Jones's theory of punctuated equilibrium, based on changes on policy images held by the relevant policy actors and the general public; Schattschneider's mobilization of bias; Cobb, Ross, and Ross's three models of agenda-building; Ripley and Franklin's theory of subgovernments; and Lindblom's emphasis on the role of the social scientist in responsible policymaking. In order to contribute productively to the policy process, social scientists must develop ethical, productive ways of responding to the ways in which other policy actors will use, and possibly distort, their findings. [source] Project management and high-value superyacht projects: An improvisational and temporal perspectivePROJECT MANAGEMENT JOURNAL, Issue 1 2010Steve Leybourne Abstract This article considers specific elements of the project management of high-value deliverables in an under-researched sector. Specifically, it looks at ways in which change is accommodated in complex projects where scope, delivery, and cost are relatively inflexible. An emerging literature considers improvisational working within project-based work, which dilutes the "plan, then execute" paradigm that has shaped project work for some time. This research contributes to the temporal and rhythmic aspects of work in this area, linking with extant theory on, among other areas, punctuated equilibrium and organizational "rhythm," and identifies parallels between improvised project work and established academic theory. [source] Transposable elements: powerful facilitators of evolutionBIOESSAYS, Issue 7 2009Keith R. Oliver Abstract Transposable elements (TEs) are powerful facilitators of genome evolution, and hence of phenotypic diversity as they can cause genetic changes of great magnitude and variety. TEs are ubiquitous and extremely ancient, and although harmful to some individuals, they can be very beneficial to lineages. TEs can build, sculpt, and reformat genomes by both active and passive means. Lineages with active TEs or with abundant homogeneous inactive populations of TEs that can act passively by causing ectopic recombination are potentially fecund, adaptable, and taxonate readily. Conversely, taxa deficient in TEs or possessing heterogeneous populations of inactive TEs may be well adapted in their niche, but tend to prolonged stasis and may risk extinction by lacking the capacity to adapt to change, or diversify. Because of recurring intermittent waves of TE infestation, available data indicate a compatibility with punctuated equilibrium, in keeping with widely accepted interpretations of evidence from the fossil record. We propose a general and holistic synthesis on how the presence of TEs within genomes makes them flexible and dynamic, so that genomes themselves are powerful facilitators of their own evolution [source] | ||||||||||||||||