Heritable Variation and Competitive Selection as the Mechanism of Sociocultural Evolution

2002 ◽  
Author(s):  
W. G. Runciman
Keyword(s):  
Natural Selection ◽  
Social Behaviour ◽  
Human Populations ◽  
Heritable Variation ◽  
Cultural Selection ◽  
Competitive Selection ◽  
Evolutionary Forces ◽  
Clear Case ◽  
Sociocultural Evolution ◽  
Sociocultural Selection

This chapter examines how heritable variation and competitive selection promote sociocultural evolution, based on the application of Charles Darwin's ‘descent with modification’ to human behaviour. It first considers the extent to which sociocultural selection can be reduced to natural selection before explaining how cultural and natural selection, despite being different evolutionary forces, act simultaneously on human populations and their social behaviour. It then cites the practice of venality in France between 1467 and 1789 as a clear case of replication through social rather than cultural selection.

Cultural Selection, Axiological Reasoning, and Paradiastole (I)

2007 ◽  
Vol 48 (1) ◽  
pp. 173-189 ◽  
Author(s):  
W. G. Runciman
Keyword(s):  
Cultural Evolution ◽  
Practical Reasoning ◽  
Attitudes And Beliefs ◽  
Heritable Variation ◽  
Cultural Selection ◽  
Competitive Selection ◽  
Rhetorical Device ◽  
Selection For

In the course of cultural evolution, both attitudes and beliefs are continuously modified by heritable variation and competitive selection. For Raymond Boudon, this process is exactly the same in the two cases, since in both axiological and practical reasoning consensus depends on a shared acknowledgement that the agreed conclusions are the products of “strong” reasons. His argument is, however, open to objection on psychological and sociological as well as philosophical grounds, and is vulnerable to the traditional rhetorical device known as paradiastole.

scholarly journals Dynamics of natural selection in two generations (on the example of the population of the Kirovograd region)

2021 ◽  
Vol 29 ◽  
pp. 152-156
Author(s):  
K. K. Kovleva ◽  
N.A. Kozak
Keyword(s):  
Natural Selection ◽  
First Generation ◽  
Second Generation ◽  
Selection Index ◽  
Genetic Load ◽  
Modern Medicine ◽  
Reproductive Age ◽  
Human Populations ◽  
Medical Histories ◽  
Total Selection

Aim. In connection with the success of modern medicine, the pressure of natural selection in various civilized human populations is weakening, which leads to the accumulation of a genetic load. The purpose of this work was to trace the change in the intensity of natural selection among population of the Kirovograd region in two successive generations. Methods. The collection of material was carried out in 2020 and 2021. Anonymous questionnaires were conducted and medical histories of women of post-reproductive age of the Kirovograd region were studied. The first generation included 40 women born in 1937–1959; the second generation consists of 273 women born in 1960–1981. Results. The total selection index was 0.27 in the first generation, and 0.37 in the second generation. The percentage of women who have not had pregnancies increased from the first generation to the second from 2.5 to 3.7, respectively. Conclusions. The index of total selection in the Kirovograd region population for one generation increased by almost one and a half times (from 0.27 to 0.37), as well as the index of differential fertility (from 0.25 to 0.35). Keywords: reproductive characteristics, Kirovograd population, Crow's index, selection, generations.

scholarly journals Genomic and demographic processes differentially influence genetic variation across the X chromosome

2021 ◽  
Author(s):  
Daniel J. Cotter ◽  
Timothy H. Webster ◽  
Melissa A. Wilson
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Linkage Disequilibrium ◽  
X Chromosome ◽  
Global Scale ◽  
Careful Consideration ◽  
Human Populations ◽  
Evolutionary Forces ◽  
Ideal System ◽  
Demographic Patterns

AbstractMutation, recombination, selection, and demography affect genetic variation across the genome. Increased mutation and recombination both lead to increases in genetic diversity in a region-specific manner, while complex demographic patterns shape patterns of diversity on a more global scale. The X chromosome is particularly interesting because it contains several distinct regions that are subject to different combinations and strengths of these processes, notably the pseudoautosomal regions (PARs) and the X-transposed region (XTR). The X chromosome thus can serve as a unique model for studying how genetic and demographic forces act in different contexts to shape patterns of observed variation. Here we investigate diversity, divergence, and linkage disequilibrium in each region of the X chromosome using genomic data from 26 human populations. We find that both diversity and substitution rate are consistently elevated in PAR1 and the XTR compared to the rest of the X chromosome. In contrast, linkage disequilibrium is lowest in PAR1 and highest on the non-recombining X chromosome, with the XTR falling in between, suggesting that the XTR (usually included in the non-recombining X) may need to be considered separately in future studies. We also observed strong population-specific effects on genetic diversity; not only does genetic variation differ on the X and autosomes among populations, but the effects of linked selection on the X relative to autosomes have been shaped by population-specific history. The substantial variation in patterns of variation across these regions provides insight into the unique evolutionary history contained within the X chromosome.Significance StatementDemography and selection affect the X chromosome differently from non-sex chromosomes. However, the X chromosome can be subdivided into multiple distinct regions that facilitate even more fine-scaled assessment of these processes. Here we study regions of the human X chromosome in 26 populations to find evidence that recombination may be mutagenic in humans and that the X-transposed region may undergo recombination. Further we observe that the effects of selection and demography act differently on the X chromosome relative to the autosomes across human populations. Together, our results highlight profound regional differences across the X chromosome, simultaneously making it an ideal system for exploring the action of evolutionary forces as well as necessitating its careful consideration and treatment in genomic analyses.

scholarly journals Evolution of gene regulatory networks by means of selection and random genetic drift

2018 ◽  
Author(s):  
Antonios Kioukis ◽  
Pavlos Pavlidis
Keyword(s):  
Natural Selection ◽  
Positive Selection ◽  
Genetic Drift ◽  
Regulatory Networks ◽  
Fitness Landscape ◽  
Random Genetic Drift ◽  
Maturation Period ◽  
Evolutionary Forces ◽  
Gene Regulatory

The evolution of a population by means of genetic drift and natural selection operating on a gene regulatory network (GRN) of an individual has not been scrutinized in depth. Thus, the relative importance of various evolutionary forces and processes on shaping genetic variability in GRNs is understudied. Furthermore, it is not known if existing tools that identify recent and strong positive selection from genomic sequences, in simple models of evolution, can detect recent positive selection when it operates on GRNs. Here, we propose a simulation framework, called EvoNET, that simulates forward-in-time the evolution of GRNs in a population. Since the population size is finite, random genetic drift is explicitly applied. The fitness of a mutation is not constant, but we evaluate the fitness of each individual by measuring its genetic distance from an optimal genotype. Mutations and recombination may take place from generation to generation, modifying the genotypic composition of the population. Each individual goes through a maturation period, where its GRN reaches equilibrium. At the next step, individuals compete to produce the next generation. As time progresses, the beneficial genotypes push the population higher in the fitness landscape. We examine properties of the GRN evolution such as robustness against the deleterious effect of mutations and the role of genetic drift. We confirm classical results from Andreas Wagner’s work that GRNs show robustness against mutations and we provide new results regarding the interplay between random genetic drift and natural selection.

Human self-selection as a mechanism of human societal evolution: A critique of the cultural selection argument

2021 ◽  
pp. 136843102110497
Author(s):  
Shanyang Zhao
Keyword(s):  
Natural Selection ◽  
Reproductive Success ◽  
Social Research ◽  
Cultural Adaptations ◽  
Neolithic Revolution ◽  
Cultural Selection ◽  
Self Selection ◽  
New Type ◽  
Fitness Criterion ◽  
Societal Evolution

Natural selection is the main mechanism that drives the evolution of species, including human societies. Under natural selection, human species responds through genetic and cultural adaptations to internal and external selection pressures for survival and reproductive success. However, this theory is ineffective in explaining human societal evolution in the Holocene and a cultural selection argument has been made to remedy the theory. The present article provides a critique of the cultural selection argument and proposes an alternative conception that treats human self-selection as an emergent mechanism of human societal evolution characterized by a new type of selection pressure and a separate fitness criterion. Specifically, the evolution of human societies is divided into two major periods, each driven by a different mode of selection: natural selection acting on genes and cultures for survival and reproductive success prior to the Neolithic Revolution, and human self-selection acting on cultures – and potentially genes as well – for thrival and prosperous living after the Neolithic Revolution. The conditions for the transition from the first mode of selection to the second and the implications of this transition for social research are also discussed.

The Current Bottleneck of Knowledge Management and How Information Technology can be Successfully Used to Reduce it

2011 ◽  
pp. 289-315
Author(s):  
Ricardo Salim ◽  
Carlos Ferran
Keyword(s):  
Artificial Intelligence ◽  
Information Technology ◽  
Knowledge Management ◽  
Natural Selection ◽  
Field Tests ◽  
Cultural Selection

Knowledge is generated and propogated by cultural selection, a process that—like it genetic counterpart, natural selection—consumes much time and resources in contrasting every new (or mutated) information with reality. However, if we hasten to minimize the field tests or marketing tests—forms of cultural selection—we run into the risk of not testing the knowledge sufficiently and make a deficient contrast with reality. In this chapter we present the concept of pragmatic minimization as the compromise of minimizing the amount of resources invested in contrasting the newly acquired knowledge with reality, while not falling into a lack of realism—blind idealism—or a cominatorial explosion of mental possibilities. Then, we advocate “simulated praxis” and a “more pragmatic artificial intelligence” as new avenues to optimally solve the problem of pragmatic minimization.

scholarly journals Genetic Variation Explains Changes in Susceptibility in a Naïve Host Against an Invasive Forest Pathogen: The Case of Alder and the Phytophthora alni Complex

2020 ◽  
Vol 110 (2) ◽  
pp. 517-525 ◽  
Author(s):  
Miguel A. Redondo ◽  
Jan Stenlid ◽  
Jonàs Oliva
Keyword(s):  
Genetic Variation ◽  
Natural Selection ◽  
Transmission Rate ◽  
Alternative Hypothesis ◽  
Simulated Data ◽  
Alnus Glutinosa ◽  
Heritable Variation ◽  
Narrow Sense Heritability ◽  
Black Alder

Predicting whether naïve tree populations have the potential to adapt to exotic pathogens is necessary owing to the increasing rate of invasions. Adaptation may occur as a result of natural selection when heritable variation in terms of susceptibility exists in the naïve population. We searched for signs of selection on black alder (Alnus glutinosa) stands growing on riverbanks invaded by two pathogens differing in aggressiveness, namely, Phytophthora uniformis (PU) and Phytophthora × alni (PA). We compared the survival and heritability measures from 72 families originating from six invaded and uninvaded (naïve) sites by performing in vitro inoculations. The results from the inoculations were used to assess the relative contribution of host genetic variation on natural selection. We found putative signs of natural selection on alder exerted by PU but not by PA. For PU, we found a higher survival in families originating from invaded sites compared with uninvaded sites. The narrow sense heritability of susceptibility to PU of uninvaded populations was significantly higher than to PA. Simulated data supported the role of heritable genetic variation on natural selection and discarded a high aggressiveness of PA decreasing the transmission rate as an alternative hypothesis for a slow natural selection. Our findings expand on previous attempts of using heritability as a predictor for the likelihood of natural adaptation of naïve tree populations to invasive pathogens. Measures of genetic variation can be useful for risk assessment purposes or when managing Phytophthora invasions.

scholarly journals Characterization of a Pseudomonas putida Rough Variant Evolved in a Mixed-Species Biofilm with Acinetobacter sp. Strain C6

2007 ◽  
Vol 189 (13) ◽  
pp. 4932-4943 ◽  
Author(s):  
Susse Kirkelund Hansen ◽  
Janus A. J. Haagensen ◽  
Morten Gjermansen ◽  
Thomas Martini Jørgensen ◽  
Tim Tolker-Nielsen ◽  
...  
Keyword(s):  
Natural Selection ◽  
Pseudomonas Putida ◽  
Wild Type ◽  
Low Oxygen ◽  
Phenotypic Characteristics ◽  
Mixed Species ◽  
Evolutionary Forces ◽  
Enhanced Production ◽  
Oxygen Starvation ◽  
Biofilm Development

ABSTRACT Genetic differentiation by natural selection is readily observed among microbial populations, but a more comprehensive understanding of evolutionary forces, genetic causes, and resulting phenotypic advantages is not often sought. Recently, a surface population of Pseudomonas putida bacteria was shown to evolve rapidly by natural selection of better-adapted variants in a mixed-species biofilm consortium (S. K. Hansen, P. B. Rainey, J. A. Haagensen, and S. Molin, Nature 445:533-536, 2007). Adaptation was caused by mutations in a wapH homolog (PP4943) involved in core lipopolysaccharide biosynthesis. Here we investigate further the biofilm physiology and the phenotypic characteristics of the selected P. putida rough colony variants. The coexistence of the P. putida population in a mixed-species biofilm with Acinetobacter sp. strain C6 is dependent on the benzoate excreted from Acinetobacter during the catabolism of benzyl alcohol, the sole carbon source. Examination of biofilm development and the dynamics of the wild-type consortium revealed that the biofilm environment became oxygen limited, possibly with low oxygen concentrations around Acinetobacter microcolonies. In contrast to P. putida wild-type cells, which readily dispersed from the mixed-species biofilm in response to oxygen starvation, the rough variant cells displayed a nondispersal phenotype. However, in monospecies biofilms proliferating on benzoate, the rough variant (like the wild-type population) dispersed in response to oxygen starvation. A key factor explaining this conditional, nondispersal phenotype is likely to be the acquired ability of the rough variant to coaggregate specifically with Acinetobacter cells. We further show that the P. putida rough variant displayed enhanced production of a cellulose-like polymer as a consequence of the mutation in wapH. The resulting phenotypic characteristics of the P. putida rough variant explain its enhanced fitness and ability to form tight structural associations with Acinetobacter microcolonies.

scholarly journals The emergence of latent infection in the early evolution of Mycobacterium tuberculosis

2016 ◽  
Vol 283 (1831) ◽  
pp. 20160499 ◽  
Author(s):  
Rebecca H. Chisholm ◽  
Mark M. Tanaka
Keyword(s):  
Mathematical Model ◽  
Immune Response ◽  
Mycobacterium Tuberculosis ◽  
Genetic Variation ◽  
Natural Selection ◽  
Natural History ◽  
Latent Infection ◽  
Human Populations ◽  
Safe Harbour ◽  
Active Disease

Mycobacterium tuberculosis has an unusual natural history in that the vast majority of its human hosts enter a latent state that is both non-infectious and devoid of any symptoms of disease. From the pathogen perspective, it seems counterproductive to relinquish reproductive opportunities to achieve a détente with the host immune response. However, a small fraction of latent infections reactivate to the disease state. Thus, latency has been argued to provide a safe harbour for future infections which optimizes the persistence of M. tuberculosis in human populations. Yet, if a pathogen begins interactions with humans as an active disease without latency, how could it begin to evolve latency properties without incurring an immediate reproductive disadvantage? We address this question with a mathematical model. Results suggest that the emergence of tuberculosis latency may have been enabled by a mechanism akin to cryptic genetic variation in that detrimental latency properties were hidden from natural selection until their expression became evolutionarily favoured.

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