Multiply concurrent replication

2004 ◽  
Vol 27 (6) ◽  
pp. 902-904
Author(s):  
David L. Hull ◽  
Sigrid S. Glenn

If selection is interpreted as involving repeated cycles of replication, variation, and environmental interaction so structured that environmental interaction causes replication to be differential, then selection in gene-based biological evolution and the reaction of the immune system to antigens are relatively unproblematic examples of selection processes. Operant learning and cultural evolution pose more serious problems. In this response we deal with operant learning as a selection process.

2001 ◽  
Vol 24 (3) ◽  
pp. 559-569 ◽  
Author(s):  
David L. Hull ◽  
Rodney E. Langman ◽  
Sigrid S. Glenn

For a long time, several natural phenomena have been considered unproblematically selection processes in the same sense of “selection.” In our target article we dealt with three of these phenomena: gene-based selection in biological evolution, the reaction of the immune system to antigens, and operant learning. We characterize selection in terms of three processes (variation, replication, and environmental interaction) resulting in the evolution of lineages via differential replication. Our commentators were largely supportive with respect to variation and environmental interaction but critical with respect to replication, in particular its appeal to information. With some reservations, our commentators think that our general analysis of selection may fit gene-based selection in biological evolution and the reaction of the immune system but not operant learning. If nothing else, this article shows that the notion of selection is not as straightforward as it may seem.


2001 ◽  
Vol 24 (3) ◽  
pp. 511-528 ◽  
Author(s):  
David L. Hull ◽  
Rodney E. Langman ◽  
Sigrid S. Glenn

Authors frequently refer to gene-based selection in biological evolution, the reaction of the immune system to antigens, and operant learning as exemplifying selection processes in the same sense of this term. However, as obvious as this claim may seem on the surface, setting out an account of “selection” that is general enough to incorporate all three of these processes without becoming so general as to be vacuous is far from easy. In this target article, we set out such a general account of selection to see how well it accommodates these very different sorts of selection. The three fundamental elements of this account are replication, variation, and environmental interaction. For selection to occur, these three processes must be related in a very specific way. In particular, replication must alternate with environmental interaction so that any changes that occur in replication are passed on differentially because of environmental interaction.One of the main differences among the three sorts of selection that we investigate concerns the role of organisms. In traditional biological evolution, organisms play a central role with respect to environmental interaction. Although environmental interaction can occur at other levels of the organizational hierarchy, organisms are the primary focus of environmental interaction. In the functioning of the immune system, organisms function as containers. The interactions that result in selection of antibodies during a lifetime are between entities (antibodies and antigens) contained within the organism. Resulting changes in the immune system of one organism are not passed on to later organisms. Nor are changes in operant behavior resulting from behavioral selection passed on to later organisms. But operant behavior is not contained in the organism because most of the interactions that lead to differential replication include parts of the world outside the organism. Changes in the organism's nervous system are the effects of those interactions. The role of genes also varies in these three systems. Biological evolution is gene-based (i.e., genes are the primary replicators). Genes play very different roles in operant behavior and the immune system. However, in all three systems, iteration is central. All three selection processes are also incredibly wasteful and inefficient. They can generate complexity and novelty primarily because they are so wasteful and inefficient.


2001 ◽  
Vol 24 (3) ◽  
pp. 553-554 ◽  
Author(s):  
V. S. Rotenberg

The interaction of the organism with the environment requires not only reactive, but also active behavior (i.e., search activity) which helps subject to meet the challenge of the uncertainty of the environment. A positive feedback between active behavior and immune system makes the selection process effective.


Genetics ◽  
2000 ◽  
Vol 154 (4) ◽  
pp. 1851-1864 ◽  
Author(s):  
John A Woolliams ◽  
Piter Bijma

AbstractTractable forms of predicting rates of inbreeding (ΔF) in selected populations with general indices, nonrandom mating, and overlapping generations were developed, with the principal results assuming a period of equilibrium in the selection process. An existing theorem concerning the relationship between squared long-term genetic contributions and rates of inbreeding was extended to nonrandom mating and to overlapping generations. ΔF was shown to be ~¼(1 − ω) times the expected sum of squared lifetime contributions, where ω is the deviation from Hardy-Weinberg proportions. This relationship cannot be used for prediction since it is based upon observed quantities. Therefore, the relationship was further developed to express ΔF in terms of expected long-term contributions that are conditional on a set of selective advantages that relate the selection processes in two consecutive generations and are predictable quantities. With random mating, if selected family sizes are assumed to be independent Poisson variables then the expected long-term contribution could be substituted for the observed, providing ¼ (since ω = 0) was increased to ½. Established theory was used to provide a correction term to account for deviations from the Poisson assumptions. The equations were successfully applied, using simple linear models, to the problem of predicting ΔF with sib indices in discrete generations since previously published solutions had proved complex.


Much has been said at the symposium about the pre-eminent role of the brain in the continuing emergence of man. Tobias has spoken of its explosive enlargement during the last 1 Ma, and how much of its enlargement in individual ontogeny is postnatal. We are born before our brains are fully grown and ‘wired up ’. During our long adolescence we build up internal models of the outside world and of the relations of parts of our bodies to it and to one another. Neurons that are present at birth spread their dendrites and project axons which acquire their myelin sheaths, and establish innumerable contacts with other neurons, over the years. New connections are formed; genetically endowed ones are stamped in or blanked off. People born without arms may grow up to use their toes in skills that are normally manual. Tobias, Darlington and others have stressed the enormous survival value of adaptive behaviour and the ‘positive feedback’ relation between biological and cultural evolution. The latter, the unique product of the unprecedentedly rapid biological evolution of big brains, advances on a time scale unknown to biological evolution.


2018 ◽  
Author(s):  
Kenny Smith

Recent work suggests that linguistic structure develops through cultural evolution, as a consequence of the repeated cycle of learning and use by which languages persist. This work has important implications for our understanding of the evolution of the cognitive basis for language: in particular, human language and the cognitive capacities underpinning it are likely to have been shaped by co-evolutionary processes, where the cultural evolution of linguistic systems is shaped by and in turn shapes the biological evolution of the capacities underpinning language learning. I review several models of this co-evolutionary process, which suggest that the precise relationship between evolved biases in individuals and the structure of linguistic systems depends on the extent to which cultural evolution masks or unmasks individual-level cognitive biases from selection. I finish by discussing how these co-evolutionary models might be extended to cases where the biases involved in learning are themselves shaped by experience, as is the case for language.


2015 ◽  
Vol 5 (1) ◽  
pp. 113-132
Author(s):  
Mehmet Canbulat ◽  
Ayşe Nur Kutluca Canbulat

The aim of this study is to analyze the selection process of teacher candidates in Turkey and Austria education systems. In the study, the Upper Austria Higher Education documents on the selection processes were examined and the teacher candidates' selection processes were observed. For the Turkish side, the higher education selection handbooks by Student Selection and Placement Center (OSYM) were examined and 96 teacher candidates were interviewed. According to the findings, in Austria's teacher education system, the students should volunteer to be a teacher and also must fulfill compliance of the profession. In Turkey, on the other hand, the teacher candidates were selected according to the central examination results conducted by ÖSYM. While scores are taken into account in the areas such as mathematics, social sciences, science, geometry, etc., the evaluation related to the individual reasons for seeking this profession, individuals' eligibility of the teaching profession and personal characteristics are not considered in this selection process. The interview results revealed that while some of the candidates were willing to become a teacher, others reported obligation to do so and some stated that they accidently selected to be a teacher.


2020 ◽  
Author(s):  
Fredrik Jansson ◽  
Elliot Aguilar ◽  
Alberto Acerbi ◽  
Magnus Enquist

A specific goal of the field of cultural evolution is to understand how processes of transmission and selection at the individual level lead to population-wide patterns of cultural diversity and change. Models of cultural evolution have typically assumed that traits are independent of one another and essentially exchangeable. But culture has a structure: traits bear relationships to one another that affect the transmission and selection process itself. Here we introduce a modelling framework to explore the effect of cultural structure on the process of learning. Through simulations, we find that introducing this simple structure changes the cultural dynamics. Based on a basic filtering mechanism for parsing these relationships, more elaborate cultural filters emerge. In a mostly incompatible cultural domain of traits, these filters organise culture into mostly (but not fully) consistent and stable systems. Incompatible domains produce small homogeneous cultures, while more compatibility increases size, diversity, and group divergence. When individuals copy based on a trait's features (here, its compatibility relationships) they produce more homogeneous cultures than when they copy based on the agent carrying the cultural trait. We discuss the implications of considering cultural systems and filters in the dynamics of cultural change.


2021 ◽  
Vol 13 (2) ◽  
pp. 145-152
Author(s):  
Mohammad Mahdi Hatef ◽  

Evolutionary models for scientific change are generally based on an analogy between scientific changes and biological evolution. Some dissimilarity cases, however, challenge this analogy. An issue discussed in this essay is that despite natural evolution, which is currently considered to be non-globally progressive, science is a phenomenon that we understand as globally progressive. David Hull's solution to this disanalogy is to trace the difference back to their environments, in which processes of natural selection and conceptual selection occur. I will provide two arguments against this solution, showing that Hull's formulation of natural selection prohibits him from removing the environment from the selection process. Then I point to a related tension in his theory, between realism and externalism in science, and give some suggestions to solve these tensions.


Author(s):  
William Hoppitt ◽  
Kevin N. Laland

This chapter describes a variety of approaches to modeling social learning, cultural evolution, and gene-culture coevolution. The model-building exercise typically starts with a set of assumptions about the key processes to be explored, along with the nature of their relations. These assumptions are then translated into the mathematical expressions that constitute the model. The operation of the model is then investigated, normally using a combination of analytical mathematical techniques and simulation, to determine relevant outcomes, such as the equilibrium states or patterns of change over time. The chapter presents examples of the modeling of cultural transmission and considers parallels between cultural and biological evolution. It then discusses theoretical approaches to social learning and cultural evolution, including population-genetic style models of cultural evolution and gene-culture coevolution, neutral models and random copying, social foraging theory, spatially explicit models, reaction-diffusion models, agent-based models, and phylogenetic models.


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