Rapid Evolution of Social Learning

Culture is widely thought to be beneficial when social learning is less costly than individual learning and thus may explain the enormous ecological success of humans. Rogers (1988. Does biology constrain culture. Am. Anthropol. 90: 819–831) contradicted this common view by showing that the evolution of social learning does not necessarily increase the net benefits of learned behaviours in a variable environment. Using simulation experiments, we re-analysed extensions of Rogers' model after relaxing the assumption that genetic evolution is much slower than cultural evolution. Our results show that this assumption is crucial for Rogers' finding. For many parameter settings, genetic and cultural evolution occur on the same time scale, and feedback effects between genetic and cultural dynamics increase the net benefits. Thus, by avoiding the costs of individual learning, social learning can increase ecological success. Furthermore, we found that rapid evolution can limit the evolution of complex social learning strategies, which have been proposed to be widespread in animals.Human Evolutionary Biolog

Investigating the Impact of Observation Errors on the Statistical Performance of Network-based Diffusion Analysis

Experiments in captivity have provided evidence for social learning, but it remains challenging to demon- strate social learning in the wild. Recently, we developed network-based diffusion analysis (NBDA; 2009) as a new approach to inferring social learning from observational data. NBDA fits alternative models of asocial and social learning to the diffusion of a behavior through time, where the potential for social learning is related to a social network. Here, we investigate the performance of NBDA in relation to variation in group size, network heterogeneity, observer sampling errors, and duration of trait diffusion. We find that observation errors, when severe enough, can lead to increased Type I error rates in detecting social learning. However, elevated Type I error rates can be prevented by coding the observed times of trait acquisition into larger time units. Collectively, our results provide further guidance to applying NBDA and demonstrate that the method is more robust to sampling error than initially expected. Supplemental materials for this article may be downloaded from http:// lb.psychonomic-journals.org/content/supplemental.Human Evolutionary Biolog

An Investigation of User-Led System Design: Rational and Political Perspectives

and organizational factors affecting system implementation (Ives and Olson, in press; RobeyandFarrow, 1982; Fuerstand Cheney, 1982; Lucas 1976).However,littleresearchhas captured the dynamics of user involvement during system development Consequently, we 1mow little about such activities and events as user and designer interaction, top management pressures, political activities, or the role of personnel turnover. To team more about these dynamics, longitudinal research needs to be conducted throughout the system development process. Longitudinal data collection serves two important research objectives: improved measurement validity, and alternative interpretations of events. Events may be described in a more valid manner when data is collected as events occur. This guarantees greater independence of the construct user involvement from the construct system success. In reconstruction studies, respondents\u27 current experience with a system may influence their perceptions of involvement Second, longitudinal study makes it easier to collect alternative interpretations of events in the development process. Activities that are ostensibly undertaken for rational reasons (to deliver a better system) may also serve the political interests of the actors (Robey and Markus, 1984). Longitudinal methods permit respondents\u27 interpretations of these events to be collected as they occur. Thmugh longitudinal research methods, the events of development processes may be described and then interpreted in two ways. One interpretation stresses the rational objectives and methods in development The second interpretation of the same events identifies political themes. These two perspectives coexist and complement one anothe

Assessing development strategies and Africa's food and nutrition security

"On average, a typical developing country in Africa is assisted by about 30 aid institutions in the implementation of development strategies, yet Africa is still far from achieving food and nutrition security. Adequate access to food that is necessary for food security must be complemented with provision of health services, education, sanitary environments, and safe water sources, among other resources, to achieve nutrition security." from TextDevelopment assistance ,Food security Africa ,Nutrition Security ,Health services ,Water quality ,Sanitation ,Development strategies ,

Development strategies and food and nutrition security in Africa: an assessment

"Momentum is building in and around Africa today for policy action to decisively confront hunger and malnutrition. If we are to succeed, it is vital that food and nutrition security strategies be both sound and able to be implemented. Ultimately, strategies deficient in either of these two areas will be ineffectual. Lessons from past strategies provide a valuable resource in the design of future strategies, yet there is a dearth of programmatic information and rigorous evaluations of the approaches used in the past. With this in mind, the authors of this 2020 discussion paper review the multitude of approaches and strategies for achieving food and nutrition security in Africa within the context of development over the past four decades. They assess the extent to which these plans have been implemented and identify the key constraints and limitations, along with the priority investments needed for more effective design and implementation in the future." Foreword by Joachim von Braun, Director General, IFPRIFood policy, Hunger, Malnutrition Africa, Food security Africa, Development policies, Assessment, Investments,

Capacitors with low equivalent series resistance

An electric double layer capacitor (EDLC) in a coin or button cell configuration having low equivalent series resistance (ESR). The capacitor comprises mesh or other porous metal that is attached via conducting adhesive to one or both the current collectors. The mesh is embedded into the surface of the adjacent electrode, thereby reducing the interfacial resistance between the electrode and the current collector, thus reducing the ESR of the capacitor

Xiamen Call for Action: Building the Brain of the City- Universal Principles of Urban Health

The question of how to achieve healthy, sustainable urban futures demands a singular emphasis. The scale and rate of change of modern urbanisation is unprecedented—so much so that it threatens the health gains of the past century. Urbanisation is the greatest ecological shift in human history, and in modern times has attained dimensions never seen before. We have mere decades to enact the greatest transformational change the planet has ever seen, if we are to safeguard a sustainable future. Indeed, the scope, scale, and ambition of transformative efforts need to accelerate dramatically, if humanity is to achieve sustainability before being overwhelmed by global change.info:eu-repo/semantics/publishedVersio