scholarly journals Genetics and evidence for balancing selection of a sex-linked colour polymorphism in a songbird

2018 ◽  
Author(s):  
Kang-Wook Kim ◽  
Benjamin C. Jackson ◽  
Hanyuan Zhang ◽  
David P. L. Toews ◽  
Scott A. Taylor ◽  
...  

AbstractColour polymorphisms play a key role in sexual selection and speciation, yet the mechanisms that generate and maintain them are not fully understood. Here, we use genomic and transcriptomic tools to identify the precise genetic architecture and evolutionary history of a sex-linked colour polymorphism in the Gouldian finch Erythrura gouldiae that is also accompanied by remarkable differences in behaviour and physiology. We find that differences in colour are associated with an ~72-kbp region of the Z chromosome in a putative regulatory region for follistatin, an antagonist of the TGF-β superfamily genes. The region is highly differentiated between morphs, unlike the rest of the genome, yet we find no evidence that an inversion is involved in maintaining the distinct haplotypes. Coalescent simulations confirm that there is elevated nucleotide diversity and an excess of intermediate frequency alleles at this locus. We conclude that this pleiotropic colour polymorphism is most probably maintained by balancing selection.

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Kang-Wook Kim ◽  
Benjamin C. Jackson ◽  
Hanyuan Zhang ◽  
David P. L. Toews ◽  
Scott A. Taylor ◽  
...  

Author(s):  
Didier Debaise

Process and Reality ends with a warning: ‘[t]he chief danger to philosophy is narrowness in the selection of evidence’ (PR, 337). Although this danger of narrowness might emerge from the ‘idiosyncrasies and timidities of particular authors, of particular social groups, of particular schools of thought, of particular epochs in the history of civilization’ (PR, 337), we should not be mistaken: it occurs within philosophy, in its activity, its method. And the fact that this issue arises at the end of Process and Reality reveals the ambition that has accompanied its composition: Whitehead has resisted this danger through the form and ambition of his speculative construction. The temptation of a narrowness in selection attempts to expel speculative philosophy at the same time as it haunts each part of its system.


2014 ◽  
Vol 3 ◽  
pp. 127-137
Author(s):  
Tatsiana Hiarnovich

The paper explores the displace of Polish archives from the Soviet Union that was performed in 1920s according to the Riga Peace Treaty of 1921 and other international agreements. The aim of the research is to reconstruct the process of displace, based on the archival sources and literature. The object of the research is those documents that were preserved in the archives of Belarus and together with archives from other republics were displaced to Poland. The exploration leads to clarification of the selection of document fonds to be displaced, the actual process of movement and the explanation of the role that the archivists of Belarus performed in the history of cultural relationships between Poland and the Soviet Union. The articles of the Treaty of Riga had been formulated without taking into account the indivisibility of archive fonds that is one of the most important principles of restitution, which caused the failure of the treaty by the Soviet part.


2018 ◽  
pp. 66-70
Author(s):  
F. D. Nasirova

Causes of spinal pain are extremely varying. Sex composition of patients referring with spinal pain at the age of 16 to 35 was 35% and 65% for males and females, respectively. Peak number of complaints was observed in 30-40 years age group of highest work ability. The followings should be considered as precautions in spinal pain: onset of pain at the age of 20 and after 50, family history of oncologic diseases, walking disorders or dysfunctions of sphincters, numbness in extremities, general malaise and rapid loss of weight, pain at rest and primarily at night, as these conditions may be a warning of underlying serious disease. Selection of algorithm for radiologic investigation is decided by the treating physician.


2020 ◽  
Vol 3 (152) ◽  
pp. 92-99
Author(s):  
S. M. Geiko ◽  
◽  
O. D. Lauta

The article provides a philosophical analysis of the tropological theory of the history of H. White. The researcher claims that history is a specific kind of literature, and the historical works is the connection of a certain set of research and narrative operations. The first type of operation answers the question of why the event happened this way and not the other. The second operation is the social description, the narrative of events, the intellectual act of organizing the actual material. According to H. White, this is where the set of ideas and preferences of the researcher begin to work, mainly of a literary and historical nature. Explanations are the main mechanism that becomes the common thread of the narrative. The are implemented through using plot (romantic, satire, comic and tragic) and trope systems – the main stylistic forms of text organization (metaphor, metonymy, synecdoche, irony). The latter decisively influenced for result of the work historians. Historiographical style follows the tropological model, the selection of which is determined by the historian’s individual language practice. When the choice is made, the imagination is ready to create a narrative. Therefore, the historical understanding, according to H. White, can only be tropological. H. White proposes a new methodology for historical research. During the discourse, adequate speech is created to analyze historical phenomena, which the philosopher defines as prefigurative tropological movement. This is how history is revealed through the art of anthropology. Thus, H. White’s tropical history theory offers modern science f meaningful and metatheoretically significant. The structure of concepts on which the classification of historiographical styles can be based and the predictive function of philosophy regarding historical knowledge can be refined.


Author(s):  
Reumah Suhail

The paper addresses the different aspects of the politics of immigration, the underlying factors that motivate, force or pressurize people to move from their country of origin to new abodes in foreign nations. In the introduction the paper discusses different theories playing their due role in the immigration process, namely Realism and Constructivism. The paper examines the history of immigration and post-World War II resettlement followed by an analysis of how immigration policies are now centered towards securitization as opposed to humanitarianism after 9/11, within the scenario of globalization. Muslim migrant issues and more stringent immigration policies are also weighed in on, followed by a look at immigration in regions which are not hotspot settlement destinations. Lastly an analysis is presented about the selection of a host country a person opts for when contemplating relocation; a new concept is also discussed and determined whereby an individual can opt for “citizenship by investment” and if such a plan is an accepted means of taking on a new nationality.


GEOgraphia ◽  
2018 ◽  
Vol 20 (42) ◽  
pp. 38
Author(s):  
Lucas Labigalini Fuini

Resumo: O objetivo deste artigo é reconhecer, através de uma seleção de autores e obras, as características principais da abordagem territorial na Geografia brasileira desenvolvida desde fins dos anos 1970, quando se reconhece um verdadeiro interesse na sistematização e no conhecimento teórico sobre o conceito em nossa ciência. No perpassar por autores, objetiva-se identificar a crescente multidimensionalidade e transescalaridade que o conceito adquire nos seus conteúdos e aplicações e a mudança de sentido explicativo que assume no avançar dos anos 2000.Palavras-chave: Território. Territorialidade. História do pensamento. Político. Geografia brasileira. THE APPROACH TO THE TERRITORY IN AUTHORS OF THE BRAZILIAN GEOGRAPHY: MUTATIONS OF A CONCEPTAbstract: The purpose of this article is to recognize, through a selection of authors and works, the main features of the territorial approach in the Brazilian Geography developed since the late 1970s, when it recognizes a real interest in the systematization and theoretical knowledge about the concept in our science. In pervade by authors, aims to identify the increasing multidimensionality and transescalarity that the concept gets in their content and applications and the change in explanatory sense that assumes in advance the years 2000.Keywords: Territory. Territoriality. History of thought. Political. Brazilian geography. EL ENFOQUE SOBRE EL TERRITORIO EN AUTORES DE GEOGRAFÍA BRASILEÑA: MUTACIONES DE UN CONCEPTOResumen: El objetivo de este artículo es reconocer, a través de una selección de autores y obras, las características principales del abordaje territorial en la Geografía brasileña desarrollada desde fines de los años 1970, cuando se reconoce un verdadero interés en la sistematización y en el conocimiento teórico sobre el concepto en nuestra ciencia . En el traspaso por autores, se objetiva identificar la creciente multidimensionalidad y transescalaridad que el concepto adquiere en sus contenidos y aplicaciones y el cambio de sentido explicativo que asume a lo largo de los años 2000.Palabras-clave: Territorio. Territorialidad. Historia del pensamiento. Político. Geografía brasileña.


Genetics ◽  
2000 ◽  
Vol 155 (2) ◽  
pp. 863-872 ◽  
Author(s):  
Helmi Kuittinen ◽  
Montserrat Aguadé

AbstractAn ~1.9-kb region encompassing the CHI gene, which encodes chalcone isomerase, was sequenced in 24 worldwide ecotypes of Arabidopsis thaliana (L.) Heynh. and in 1 ecotype of A. lyrata ssp. petraea. There was no evidence for dimorphism at the CHI region. A minimum of three recombination events was inferred in the history of the sampled ecotypes of the highly selfing A. thaliana. The estimated nucleotide diversity (θTOTAL = 0.004, θSIL = 0.005) was on the lower part of the range of the corresponding estimates for other gene regions. The skewness of the frequency spectrum toward an excess of low-frequency polymorphisms, together with the bell-shaped distribution of pairwise nucleotide differences at CHI, suggests that A. thaliana has recently experienced a rapid population growth. Although this pattern could also be explained by a recent selective sweep at the studied region, results from the other studied loci and from an AFLP survey seem to support the expansion hypothesis. Comparison of silent polymorphism and divergence at the CHI region and at the Adh1 and ChiA revealed in some cases a significant deviation of the direct relationship predicted by the neutral theory, which would be compatible with balancing selection acting at the latter regions.


Genetics ◽  
1999 ◽  
Vol 152 (1) ◽  
pp. 413-425 ◽  
Author(s):  
Philip Awadalla ◽  
Deborah Charlesworth

Abstract In Brassica species, self-incompatibility is controlled genetically by haplotypes involving two known genes, SLG and SRK, and possibly an as yet unknown gene controlling pollen incompatibility types. Alleles at the incompatibility loci are maintained by frequency-dependent selection, and diversity at SLG and SRK appears to be very ancient, with high diversity at silent and replacement sites, particularly in certain “hypervariable portions of the genes. It is important to test whether recombination occurs in these genes before inferences about function of different parts of the genes can be made from patterns of diversity within their sequences. In addition, it has been suggested that, to maintain the relationship between alleles within a given S-haplotype, recombination is suppressed in the S-locus region. The high diversity makes many population genetic measures of recombination inapplicable. We have analyzed linkage disequilibrium within the SLG gene of two Brassica species, using published coding sequences. The results suggest that intragenic recombination has occurred in the evolutionary history of these alleles. This is supported by patterns of synonymous nucleotide diversity within both the SLG and SRK genes, and between domains of the SRK gene. Finally, clusters of linkage disequilibrium within the SLG gene suggest that hypervariable regions are under balancing selection, and are not merely regions of relaxed selective constraint.


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