scholarly journals Don't throw out the sympatric speciation with the crater lake water: fine-scale investigation of introgression provides equivocal support for causal role of secondary gene flow in one of the clearest examples of sympatric speciation

2018 ◽  
Vol 2 (5) ◽  
pp. 524-540 ◽  
Author(s):  
Emilie J. Richards ◽  
Jelmer W. Poelstra ◽  
Christopher H. Martin
Keyword(s):  
Gene Flow ◽  
Lake Water ◽  
Crater Lake ◽  
Sympatric Speciation ◽  
Causal Role ◽  
Fine Scale

scholarly journals Don’t throw out the sympatric species with the crater lake water: fine-scale investigation of introgression provides weak support for functional role of secondary gene flow in one of the clearest examples of sympatric speciation

2017 ◽  
Author(s):  
Emilie J. Richards ◽  
Jelmer W. Poelstra ◽  
Christopher H. Martin
Keyword(s):  
Gene Flow ◽  
Crater Lake ◽  
Morphological Diversity ◽  
Sympatric Speciation ◽  
Sympatric Species ◽  
Fine Scale ◽  
Ancestral Polymorphism ◽  
Hybrid Swarm ◽  
Weak Support ◽  
History Of

AbstractGenomic data has revealed complex histories of colonization and repeated gene flow previously unrecognized in some of the most celebrated examples of sympatric speciation and radiation. However, much of the evidence for secondary gene flow into these radiations comes from genome-wide tests, which tells us little about how gene flow potentially influenced sympatric diversification. Here we investigated whole genomes of Barombi Mbo crater lake cichlids for fine-scale patterns of introgression between species with neighboring riverine cichlid populations. We did find evidence of secondary gene flow into the radiation scattered across < 0.24% of the genome; however, the functional and genetic diversity in these regions paint no clear picture of how that variation could have contributed to the ecological and morphological diversity found in the lake. Our results suggest that either variation in novel genetic pathways introduced during secondary gene flow contributed to the radiation, or that secondary gene flow was predominantly neutral with respect to the diversification processes. We also found evidence for differential assortment of ancestral polymorphism found in riverine populations between sympatric sister species, suggesting the presence of a hybrid swarm in the past. While the history of gene flow and colonization appears to be more complicated than once thought, the lack of compelling evidence for secondary gene flow influencing diversification suggests that we should not yet rule out one of the most celebrated examples of sympatric speciation in nature.

scholarly journals Complex histories of repeated gene flow in Cameroon crater lake cichlids cast doubt on one of the clearest examples of sympatric speciation

Evolution ◽  
2015 ◽  
Vol 69 (6) ◽  
pp. 1406-1422 ◽  
Author(s):  
Christopher H. Martin ◽  
Joseph S. Cutler ◽  
John P. Friel ◽  
Cyrille Dening Touokong ◽  
Graham Coop ◽  
...  
Keyword(s):  
Gene Flow ◽  
Crater Lake ◽  
Sympatric Speciation ◽  
Cast Doubt

Do Writing Directions Influence How People Map Space onto Time?

2018 ◽  
Vol 77 (4) ◽  
pp. 173-184
Author(s):  
Wenxing Yang ◽  
Ying Sun
Keyword(s):  
Mental Representations ◽  
Space Time ◽  
Horizontal Axis ◽  
Causal Role ◽  
Writing Systems ◽  
Temporal Cognition ◽  
Japanese Speakers ◽  
Psychological Experiments ◽  
Vertical Up

Abstract. The causal role of a unidirectional orthography in shaping speakers’ mental representations of time seems to be well established by many psychological experiments. However, the question of whether bidirectional writing systems in some languages can also produce such an impact on temporal cognition remains unresolved. To address this issue, the present study focused on Japanese and Taiwanese, both of which have a similar mix of texts written horizontally from left to right (HLR) and vertically from top to bottom (VTB). Two experiments were performed which recruited Japanese and Taiwanese speakers as participants. Experiment 1 used an explicit temporal arrangement design, and Experiment 2 measured implicit space-time associations in participants along the horizontal (left/right) and the vertical (up/down) axis. Converging evidence gathered from the two experiments demonstrate that neither Japanese speakers nor Taiwanese speakers aligned their vertical representations of time with the VTB writing orientation. Along the horizontal axis, only Japanese speakers encoded elapsing time into a left-to-right linear layout, which was commensurate with the HLR writing direction. Therefore, two distinct writing orientations of a language could not bring about two coexisting mental time lines. Possible theoretical implications underlying the findings are discussed.

The Causal role of the Election Enforcement Campaign in Modern Japan

2016 ◽  
Vol 42 (0) ◽  
pp. 167-193
Author(s):  
Jongsik Kim ◽  
Keyword(s):  
Causal Role ◽  
Modern Japan

Introduction

2018 ◽  
Author(s):  
Christopher Evan Franklin
Keyword(s):  
Moral Responsibility ◽  
Free Will ◽  
Human Agency ◽  
Causal Role ◽  
Central Question ◽  
Agent Causation ◽  
The Right

This chapter lays out the book’s central question: Assuming agency reductionism—that is, the thesis that the causal role of the agent in all agential activities is reducible to the causal role of states and events involving the agent—is it possible to construct a defensible model of libertarianism? It is explained that most think the answer is negative and this is because they think libertarians must embrace some form of agent-causation in order to address the problems of luck and enhanced control. The thesis of the book is that these philosophers are mistaken: it is possible to construct a libertarian model of free will and moral responsibility within an agency reductionist framework that silences that central objections to libertarianism by simply taking the best compatibilist model of freedom and adding indeterminism in the right junctures of human agency. A brief summary of the chapters to follow is given.

scholarly journals Ecological Connectivity in Agricultural Green Infrastructure:  Suggested Criteria for Fine Scale Assessment and Planning

Land ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 807
Author(s):  
Simone Valeri ◽  
Laura Zavattero ◽  
Giulia Capotorti
Keyword(s):  
Land Cover ◽  
Green Infrastructure ◽  
Rural Areas ◽  
Urban Areas ◽  
Landscape Heterogeneity ◽  
Agricultural Landscapes ◽  
Spatial Pattern Analysis ◽  
Fine Scale ◽  
Unique Type

In promoting biodiversity conservation and ecosystem service capacity, landscape connectivity is considered a critical feature to counteract the negative effects of fragmentation. Under a Green Infrastructure (GI) perspective, this is especially true in rural and peri-urban areas where a high degree of connectivity may be associated with the enhancement of agriculture multifunctionality and sustainability. With respect to GI planning and connectivity assessment, the role of dispersal traits of tree species is gaining increasing attention. However, little evidence is available on how to select plant species to be primarily favored, as well as on the role of landscape heterogeneity and habitat quality in driving the dispersal success. The present work is aimed at suggesting a methodological approach for addressing these knowledge gaps, at fine scales and for peri-urban agricultural landscapes, by means of a case study in the Metropolitan City of Rome. The study area was stratified into Environmental Units, each supporting a unique type of Potential Natural Vegetation (PNV), and a multi-step procedure was designed for setting priorities aimed at enhancing connectivity. First, GI components were defined based on the selection of the target species to be supported, on a fine scale land cover mapping and on the assessment of land cover type naturalness. Second, the study area was characterized by a Morphological Spatial Pattern Analysis (MSPA) and connectivity was assessed by Number of Components (NC) and functional connectivity metrics. Third, conservation and restoration measures have been prioritized and statistically validated. Notwithstanding the recognized limits, the approach proved to be functional in the considered context and at the adopted level of detail. Therefore, it could give useful methodological hints for the requalification of transitional urban–rural areas and for the achievement of related sustainable development goals in metropolitan regions.

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