Faculty Opinions recommendation of Natural selection constrains neutral diversity across a wide range of species.

2015 ◽  
Author(s):  
Norman Johnson
Keyword(s):  
Natural Selection ◽  
Wide Range

scholarly journals Possible role of natural selection in the formation of tandem-repetitive noncoding DNA.

Genetics ◽  
1994 ◽  
Vol 136 (1) ◽  
pp. 333-341
Author(s):  
W Stephan ◽  
S Cho
Keyword(s):  
Natural Selection ◽  
Satellite Dna ◽  
Repeat Length ◽  
Crossing Over ◽  
Recombination Rates ◽  
Noncoding Dna ◽  
Satellite Dnas ◽  
Unequal Crossing Over ◽  
Wide Range ◽  
Long Range Ordering

Abstract A simulation model of sequence-dependent amplification, unequal crossing over and mutation is analyzed. This model predicts the spontaneous formation of tandem-repetitive patterns of noncoding DNA from arbitrary sequences for a wide range of parameter values. Natural selection is found to play an essential role in this self-organizing process. Natural selection which is modeled as a mechanism for controlling the length of a nucleotide string but not the sequence itself favors the formation of tandem-repetitive structures. Two measures of sequence heterogeneity, inter-repeat variability and repeat length, are analyzed in detail. For fixed mutation rate, both inter-repeat variability and repeat length are found to increase with decreasing rates of (unequal) crossing over. The results are compared with data on micro-, mini- and satellite DNAs. The properties of minisatellites and satellite DNAs resemble the simulated structures very closely. This suggests that unequal crossing over is a dominant long-range ordering force which keeps these arrays homogeneous even in regions of very low recombination rates, such as at satellite DNA loci. Our analysis also indicates that in regions of low rates of (unequal) crossing over, inter-repeat variability is maintained at a low level at the expense of much larger repeat units (multimeric repeats), which are characteristic of satellite DNA. In contrast, the microsatellite data do not fit the proposed model well, suggesting that unequal crossing over does not act on these very short tandem arrays.

scholarly journals Antifungals, arthropods and antifungal resistance prevention: lessons from ecological interactions

2021 ◽  
Vol 288 (1944) ◽  
pp. 20202716
Author(s):  
Steve Kett ◽  
Ayush Pathak ◽  
Stefano Turillazzi ◽  
Duccio Cavalieri ◽  
Massimiliano Marvasi
Keyword(s):  
Natural Selection ◽  
Conceptual Model ◽  
Antifungal Resistance ◽  
Antifungal Compound ◽  
Antifungal Compounds ◽  
Ecological Interactions ◽  
Eusocial Insects ◽  
Wide Range ◽  
Mutualistic Association

Arthropods can produce a wide range of antifungal compounds, including specialist proteins, cuticular products, venoms and haemolymphs. In spite of this, many arthropod taxa, particularly eusocial insects, make use of additional antifungal compounds derived from their mutualistic association with microbes. Because multiple taxa have evolved such mutualisms, it must be assumed that, under certain ecological circumstances, natural selection has favoured them over those relying upon endogenous antifungal compound production. Further, such associations have been shown to persist versus specific pathogenic fungal antagonists for more than 50 million years, suggesting that compounds employed have retained efficacy in spite of the pathogens' capacity to develop resistance. We provide a brief overview of antifungal compounds in the arthropods’ armoury, proposing a conceptual model to suggest why their use remains so successful. Fundamental concepts embedded within such a model may suggest strategies by which to reduce the rise of antifungal resistance within the clinical milieu.

Sciences of complexity and language origins: an alternative to natural selection

2001 ◽  
Vol 30 (1) ◽  
pp. 1-17 ◽  
Author(s):  
Víctor M Longa
Keyword(s):  
Natural Selection ◽  
Specific Property ◽  
Dynamic Interaction ◽  
Human Beings ◽  
Internal Factors ◽  
Language Origins ◽  
Complex Design ◽  
Wide Range ◽  
Self Organisation ◽  
Sciences Of Complexity

AbstractNatural selection is claimed to be the only way to explain complex design. The same assumption has also been held for language. However, sciences of complexity have shown, from a wide range of domains, the existence of a clear alternative: self-organisation, spontaneous patterns of order arising from chaos. According to this view, design derives from internal factors (dynamic interaction of the elements within the system) rather than from adaptation to the environment by means of selection. This paper aims to apply sciences of complexity to language origins; it shows that preexisting and well established ideas can be rethought according to such a view. The main objective of the paper is to illustrate the new and promising horizons that complexity could open as regards the origins of the most specific property of human beings.

Cooperation, Coordination, and Collective Action

2012 ◽  
Author(s):  
Lee Cronk ◽  
Beth L. Leech
Keyword(s):  
Natural Selection ◽  
Collective Action ◽  
Political Science ◽  
Empirical Research ◽  
Evolutionary Theory ◽  
Coordination Problems ◽  
Evolutionary Biologist ◽  
Wide Range ◽  
Two Bodies

This book investigates a wide range of ideas, theories, and existing empirical research relevant to the study of the complex and diverse phenomenon of human cooperation. Issues relating to cooperation are examined from the perspective of evolutionary theory, political science, and related social sciences. The book draws upon two bodies of work: Mancur Olson's The Logic of Collective Action (1965) and George C. Williams's Adaptation and Natural Selection (1966). Olson, an economist, and Williams, an evolutionary biologist, both argued that a focus on groups would not provide a complete understanding of collective action and other social behaviors. This introductory chapter discusses some important definitions relating to cooperation, with particular emphasis on collective action and collective action dilemmas, along with coordination and coordination problems. It also provides an overview of the chapters that follow.

Expression levels and codon usage patterns in nuclear genes of the filarial nematodeWucheraria bancroftiand the blood flukeSchistosoma haematobium

2016 ◽  
Vol 91 (1) ◽  
pp. 72-79 ◽  
Author(s):  
G.A. Mazumder ◽  
A. Uddin ◽  
S. Chakraborty
Keyword(s):  
Natural Selection ◽  
Codon Usage ◽  
Evolutionary Relationship ◽  
Nuclear Genes ◽  
Codon Usage Pattern ◽  
Minor Role ◽  
Usage Pattern ◽  
Genetic Characteristics ◽  
Wide Range ◽  
Usage Patterns

AbstractSynonymous codons are used with different frequencies, a phenomenon known as codon bias, which exists in many genomes and is mainly resolute by mutation and selection. To elucidate the genetic characteristics and evolutionary relationship ofWucheraria bancroftiandSchistosoma haematobiumwe examined the pattern of synonymous codon usage in nuclear genes of both the species. The mean overall GC contents ofW. bancroftiandS. haematobiumwere 43.41 and 36.37%, respectively, which suggests that genes in both the species were AT rich. The value of the High Effective Number of Codons in both species suggests that codon usage bias was weak. Both species had a wide range of P3 distribution in the neutrality plot, with a significant correlation between P12 and P3. The codons were closer to the axes in correspondence analysis, suggesting that mutation pressure influenced the codon usage pattern in these species. We have identified the more frequently used codons in these species, most codons ending with an A or T. The nucleotides A/T and C/G were not proportionally used at the third position of codons, which reveals that natural selection might influence the codon usage patterns. The regression equation of P12 on P3 suggests that natural selection might have played a major role, while mutational pressure played a minor role in codon usage pattern in both species. These results form the basis of exploring the evolutionary mechanisms and the heterologous expression of medically important proteins ofW. bancroftiandS. haematobium.

Genetic and phenotypic component in head shape of common wall lizard Podarcis muralis

2016 ◽  
Vol 37 (3) ◽  
pp. 301-310 ◽  
Author(s):  
Roberto Sacchi ◽  
Marco Mangiacotti ◽  
Stefano Scali ◽  
Michele Ghitti ◽  
Beatrice Bindolini ◽  
...  
Keyword(s):  
Natural Selection ◽  
Morphological Differentiation ◽  
Phenotypic Change ◽  
Adaptive Responses ◽  
Head Shape ◽  
Heritable Variation ◽  
Podarcis Muralis ◽  
Environmental Pressures ◽  
Common Wall ◽  
Wide Range

Head shape in lizards correlates with a wide range of environmental pressures, supporting the hypothesis that patterns of phenotypic change represent adaptive responses to selective processes. However, natural selection promotes evolutionary adaptation only if the trait under selection has enough heritable variation. In this study we used geometric morphometrics and quantitative genetics to assess the heritability patterns of the head shape and size of common wall lizards (Podarcis muralis). Genetic and phenotypic components were estimated using animal models, which showed that more than half of the variation in head morphology is inheritable. Furthermore, at least five independent patterns of genetically determined phenotypic change were detected. These outcomes confirm that morphological differentiation in common wall lizards may reliably be regarded as the result of adaptive processes driven by natural selection.

scholarly journals Natural Selection Constrains Neutral Diversity across A Wide Range of Species

PLoS Biology ◽  
2015 ◽  
Vol 13 (4) ◽  
pp. e1002112 ◽  
Author(s):  
Russell B. Corbett-Detig ◽  
Daniel L. Hartl ◽  
Timothy B. Sackton
Keyword(s):  
Natural Selection ◽  
Wide Range

Evolution: A Very Short Introduction

2017 ◽  
Author(s):  
Brian Charlesworth ◽  
Deborah Charlesworth
Keyword(s):  
New Species ◽  
Natural Selection ◽  
Evolutionary Biology ◽  
Charles Darwin ◽  
Short Introduction ◽  
Alfred Russel Wallace ◽  
Wide Range ◽  
Living Species ◽  
Evolution By Natural Selection ◽  
Special Creation

Less than 150 years ago, the view that living species were the result of special creation by God was still dominant. The recognition by Charles Darwin and Alfred Russel Wallace of the mechanism of evolution by natural selection has completely transformed our understanding of the living world, including our own origins. Evolution: A Very Short Introduction provides a summary of the process of evolution by natural selection, highlighting the wide range of evidence, and explains how natural selection gives rise to adaptations and eventually, over many generations, to new species. It introduces the central concepts of the field of evolutionary biology and discusses some of the remaining questions regarding evolutionary processes.

scholarly journals Conceptual Characterization of Threshold Concepts in Student Explanations of Evolution by Natural Selection and Effects of Item Context

2020 ◽  
Vol 19 (1) ◽  
pp. ar1 ◽  
Author(s):  
Andreas Göransson ◽  
Daniel Orraryd ◽  
Daniela Fiedler ◽  
Lena A. E. Tibell
Keyword(s):  
Natural Selection ◽  
Spatial Scale ◽  
Biology Education ◽  
Threshold Concepts ◽  
Differential Survival ◽  
Evolutionary Mechanisms ◽  
Biological Phenomena ◽  
Wide Range ◽  
Evolution By Natural Selection ◽  
The Impact

Evolutionary theory explains a wide range of biological phenomena. Proper understanding of evolutionary mechanisms such as natural selection is therefore an essential goal for biology education. Unfortunately, natural selection has time and again proven difficult to teach and learn, and students’ resulting understanding is often characterized by misconceptions. Previous research has often focused on the importance of certain key concepts such as variation, differential survival, and change in population. However, so-called threshold concepts (randomness, probability, spatial scale, and temporal scales) have also been suggested to be important for understanding of natural selection, but there is currently limited knowledge about how students use these concepts. We sought to address this lack of knowledge by collecting responses to three different natural selection items from 247 university students from Sweden and Germany. Content analysis (deductive and inductive coding) and subsequent statistical analysis of their responses showed that they overall use some spatial scale indicators, such as individuals and populations, but less often randomness or probability in their explanations. However, frequencies of use of threshold concepts were affected by the item context (e.g., the biological taxa and trait gain or loss). The results suggest that the impact of threshold concepts, especially randomness and probability, on natural selection understanding should be further explored.

scholarly journals Deciphering signatures of natural selection via deep learning

2021 ◽  
Author(s):  
Xinghu Qin ◽  
Charleston W.K. Chiang ◽  
Oscar E Gaggiotti
Keyword(s):  
Deep Learning ◽  
Natural Selection ◽  
Quantitative Traits ◽  
Predictive Power ◽  
Spatial Location ◽  
Human Genetic Variation ◽  
Environmental Attributes ◽  
Wide Range ◽  
Candidate Regions ◽  
Genomic Regions

Identifying genomic regions influenced by natural selection provides fundamental insights into a wide range of problems including human health, animal and plant breeding, and the understanding of local adaptation. We propose a new method, DeepGenomeScan, that can be used to address all these problems. It is based on the principle that the genotypes of individuals can be used to predict any associated trait; not only their phenotype but also their spatial location or the environmental attributes of the habitat they live in. We, therefore,implemented a deep learning method to detect candidate regions under selection by identifying loci that contribute the most to the predictive power of the deep neural network. Using simulations, we show that our method can successfully identify loci underlying quantitative traits subject to complex spatial patterns of selection. We apply DeepGenomeScan to a European human genetic variation dataset and posit that the loci that contribute the most to the prediction of latitude and longitude are located in genomic regions under selection. Using this approach, we identified many SNPs located within well-known genes, some of which were not identified using existing population genetics approaches, e.g. MCM6, MGAT5, TMEM163.

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