variation and selection
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Forests ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1455
Author(s):  
Qingmin Que ◽  
Chunmei Li ◽  
Buye Li ◽  
Huiyun Song ◽  
Pei Li ◽  
...  

Neolamarckia cadamba (Roxb.) Bosser is a tropical evergreen broadleaf tree species that could play an important role in meeting the increasing demand for wood products. However, multi-level genetic variation and selection efficiency for growth traits in N. cadamba is poorly characterized. We therefore investigated the efficiency of early selection in N. cadamba by monitoring the height (HT), diameter at breast height (DBH), and tree volume (V) in 39 half-sib families from 11 provenances at ages 2, 3, 4, 5, and 6 years in a progeny test. Age-related trends in growth rate, genetic parameters in multi-level, efficiency of early selection, and realized gain in multi-level for growth traits were analyzed. The result showed that genetic variation among families within provenances was higher than that among provenances. The estimated individual heritability values for the growth traits ranged from 0.05 to 0.26, indicating that the variation of growth traits in N. cadamba was subject to weak or intermediate genetic control. The age–age genetic correlations for growth traits were always positive and high (0.51–0.99), and the relationships between the genetic/phenotypic correlations and the logarithm of the age ratio (LAR) were described well by linear models (R2 > 0.85, except the fitting coefficient of genetic correlation and LAR for HT was 0.35). On the basis of an early selection efficiency analysis, we found that it is the best time to perform early selection for N. cadamba at age 5 before half-rotation, and the selection efficiencies were 157.28%, 151.56%, and 127.08% for V, DBH, and HT, respectively. Higher realized gain can be obtained by selecting superior trees from superior families. These results can be expected to provide theoretical guidance and materials for breeding programs in N. cadamba and can even be a reference for breeding strategies of other fast-growing tree species.


PLoS Genetics ◽  
2021 ◽  
Vol 17 (9) ◽  
pp. e1009824
Author(s):  
Abigail L. LaBella ◽  
Dana A. Opulente ◽  
Jacob L. Steenwyk ◽  
Chris Todd Hittinger ◽  
Antonis Rokas

2021 ◽  
pp. 305-324
Author(s):  
James E. Cutting

This chapter provides a structural description of movie units, defends the notion that movies have evolved in the direction of fitting better our capacities and preferences, and summarizes evidence that the evolved changes have encouraged narrative engagement by viewers. Arguments against any true evolution of cinema concern reproduction, genes, random variation and selection, fashion, progression, speciation, and directionality, and these are discussed and all but the means of reproduction countered. The chapter then summarizes results of the previous chapters about how narrative engagement is attained through sustained attentional focus, understanding the narrative, emotional commitment, and a feeling of presence. It also warns the reader that increased engagement does not mean better movies. Engagement is driven by the narration; the quality of the movie is surely driven by the narrative.


Genes ◽  
2021 ◽  
Vol 12 (9) ◽  
pp. 1450
Author(s):  
Margarida Alexandra Duarte ◽  
Carlos Rodríguez Fernandes ◽  
Gerald Heckel ◽  
Maria da Luz Mathias ◽  
Cristiane Bastos-Silveira

In mammals, the zona pellucida glycoprotein 3 (ZP3) is considered a primary sperm receptor of the oocyte and is hypothesized to be involved in reproductive isolation. We investigated patterns of diversity and selection in the putative sperm-binding region (pSBR) of mouse ZP3 across Cricetidae and Murinae, two hyperdiverse taxonomic groups within muroid rodents. In murines, the pSBR is fairly conserved, in particular the serine-rich stretch containing the glycosylation sites proposed as essential for sperm binding. In contrast, cricetid amino acid sequences of the pSBR were much more variable and the serine-rich motif, typical of murines, was generally substantially modified. Overall, our results suggest a general lack of species specificity of the pSBR across the two muroid families. We document statistical evidence of positive selection acting on exons 6 and 7 of ZP3 and identified several amino acid sites that are likely targets of selection, with most positively selected sites falling within or adjacent to the pSBR.


Author(s):  
Silvia Pizzocaro

Evolutionary concepts may have great appeal when studying material culture and its designed objects. As a matter of fact, there is robust tradition in using biological analogies to understand designs, as it occurs in the field of bionics, where the simulation of vital processes advocates not only an approach of a purely cognitive nature but, rather, an operative programme allowing the translation of isomorphisms between living organisms and technology into effective design solutions. More generally, natural sciences offer an uncommonly rich apparatus for analogies to be applied to the domains of the sciences of the artificial. But how widely applicable are Darwinian metaphors? To which extent do the Darwinian concepts of variation and selection provide meaningful theoretical tools across product innovation? What can they add to the analysis of product designs? To this end, this study takes the form of a literature review about evolutionary approaches to the analysis of technological change, along with a number of interpretations about the analogies between natural evolution and the dynamics of product variety generation.


Plants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1706 ◽  
Author(s):  
Deepti Nigam

Begomoviruses (family Geminiviridae, genus Begomovirus) are DNA viruses transmitted in a circulative, persistent manner by the whitefly Bemisia tabaci (Gennadius). As revealed by their wide host range (more than 420 plant species), worldwide distribution, and effective vector transmission, begomoviruses are highly adaptive. Still, the genetic factors that facilitate their adaptation to a diverse array of hosts and vectors remain poorly understood. Mutations in the virus genome may confer a selective advantage for essential functions, such as transmission, replication, evading host responses, and movement within the host. Therefore, genetic variation is vital to virus evolution and, in response to selection pressure, is demonstrated as the emergence of new strains and species adapted to diverse hosts or with unique pathogenicity. The combination of variation and selection forms a genetic imprint on the genome. This review focuses on factors that contribute to the evolution of Begomovirus and their global spread, for which an unforeseen diversity and dispersal has been recognized and continues to expand.


2021 ◽  
Vol 18 (180) ◽  
pp. 20210334
Author(s):  
Liane Gabora ◽  
Mike Steel

Natural selection successfully explains how organisms accumulate adaptive change despite that traits acquired over a lifetime are eliminated at the end of each generation. However, in some domains that exhibit cumulative, adaptive change—e.g. cultural evolution, and earliest life—acquired traits are retained; these domains do not face the problem that Darwin’s theory was designed to solve. Lack of transmission of acquired traits occurs when germ cells are protected from environmental change, due to a self-assembly code used in two distinct ways: (i) actively interpreted during development to generate a soma, and (ii) passively copied without interpretation during reproduction to generate germ cells. Early life and cultural evolution appear not to involve a self-assembly code used in these two ways. We suggest that cumulative, adaptive change in these domains is due to a lower-fidelity evolutionary process, and model it using reflexively autocatalytic and foodset-generated networks. We refer to this more primitive evolutionary process as self–other reorganization (SOR) because it involves internal self-organizing and self-maintaining processes within entities, as well as interaction between entities. SOR encompasses learning but in general operates across groups. We discuss the relationship between SOR and Lamarckism, and illustrate a special case of SOR without variation.


2021 ◽  
Author(s):  
Joshua T. Lange ◽  
Celine Y. Chen ◽  
Yuriy Pichugin ◽  
Frank Xie ◽  
Jun Tang ◽  
...  

The foundational principles of Darwinian evolution are variation, selection, and identity by descent. Oncogene amplification on extrachromosomal DNA (ecDNA) is a common event, driving aggressive tumour growth, drug resistance, and shorter survival in patients. Currently, the impact of non-chromosomal oncogene inheritance - random identity by descent - is not well understood. Neither is the impact of ecDNA on variation and selection. Here, integrating mathematical modeling, unbiased image analysis, CRISPR-based ecDNA tagging, and live-cell imaging, we identify a set of basic rules for how random ecDNA inheritance drives oncogene copy number and distribution, resulting in extensive intratumoural ecDNA copy number heterogeneity and rapid adaptation to metabolic stress and targeted cancer treatment. Observed ecDNAs obligatorily benefit host cell survival or growth and can change within a single cell cycle. In studies ranging from well-curated, patient-derived cancer cell cultures to clinical tumour samples from patients with glioblastoma and neuroblastoma treated with oncogene-targeted drugs, we show how these ecDNA inheritance rules can predict, a priori, some of the aggressive features of ecDNA-containing cancers. These properties are entailed by their ability to rapidly change their genomes in a way that is not possible for cancers driven by chromosomal oncogene amplification. These results shed new light on how the non-chromosomal random inheritance pattern of ecDNA underlies poor outcomes for cancer patients.


2021 ◽  
Vol 17 (3) ◽  
Author(s):  
Jugpreet Singh ◽  
Manyi Sun ◽  
Steven B. Cannon ◽  
Jun Wu ◽  
Awais Khan

2021 ◽  
Author(s):  
Stuart Kauffman ◽  
Andrea Roli

We approach the question, "What is Consciousness?'' in a new way, not as Descartes' "systematic doubt'', but as how organisms find their way in their world. Finding one's way involves finding possible uses of features of the world that might be beneficial or avoiding those that might be harmful. "Possible uses of X to accomplish Y'' are "Affordances''. The number of uses of X is indefinite, the different uses are unordered and are not deducible from one another. All biological adaptations are either affordances seized by heritable variation and selection or, far faster, by the organism acting in its world finding uses of X to accomplish Y. Based on this, we reach rather astonishing conclusions: 1) Strong AI is not possible. Universal Turing Machines cannot "find'' novel affordances. 2) Brain-mind is not purely classical physics for no classical physics system can be an analogue computer whose dynamical behavior can be isomorphic to "possible uses''. 3) Brain mind must be partly quantum - supported by increasing evidence at 6.0 sigma to 7.3 Sigma. 4) Based on Heisenberg's interpretation of the quantum state as "Potentia'' converted to "Actuals'' by Measurement, a natural hypothesis is that mind actualizes Potentia. This is supported at 5.2 Sigma. Then Mind's actualization of entangled brain-mind-world states are experienced as qualia and allow "seeing'' or "perceiving'' of uses of X to accomplish Y. We can and do jury-rig. Computers cannot. 5) Beyond familiar quantum computers, we consider Trans-Turing-Systems.


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