scholarly journals Correlated patterns of genetic diversity and differentiation across an avian family

2017 ◽  
Author(s):  
Benjamin M. Van Doren ◽  
Leonardo Campagna ◽  
Barbara Helm ◽  
Juan Carlos Illera ◽  
Irby J. Lovette ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Evolutionary Divergence ◽  
Relative Importance ◽  
Intrinsic Properties ◽  
Genome Scans ◽  
Pooled Sequencing ◽  
Correlated Patterns ◽  
Genomic Regions ◽  
Avian Family

ABSTRACTComparative studies of genomic differentiation among independent lineages can provide insights into aspects of the speciation process, such as the relative importance of selection and drift in shaping genomic landscapes, the role of genomic regions of high differentiation, and the prevalence of convergent molecular evolution. We investigated patterns of genetic diversity and divergence in stonechats (genus Saxicola), a widely distributed avian species complex with phenotypic variation in plumage, morphology, and migratory behavior, to ask whether similar genomic regions are important in the evolution of independent, but closely related, taxa. We used whole-genome pooled sequencing of 262 individuals from 5 taxa and found that patterns of genetic diversity and divergence are highly similar among different stonechat taxa. We then asked if these patterns remain correlated at deeper evolutionary scales and found that homologous genomic regions have become differentiated in stonechats and the closely related Ficedula flycatchers. Such correlation across a range of evolutionary divergence and among phylogenetically independent comparisons suggests that similar processes may be driving the differentiation of these independently evolving lineages, which in turn may be the result of intrinsic properties of particular genomic regions (e.g., areas of low recombination). Consequently, studies employing genome scans to search for areas important in reproductive isolation should account for corresponding regions of differentiation, as these regions may not necessarily represent speciation islands or facilitate local adaptation.

scholarly journals Correlated patterns of genetic diversity and differentiation across an avian family

2017 ◽  
Vol 26 (15) ◽  
pp. 3982-3997 ◽  
Author(s):  
Benjamin M. Van Doren ◽  
Leonardo Campagna ◽  
Barbara Helm ◽  
Juan Carlos Illera ◽  
Irby J. Lovette ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Correlated Patterns ◽  
Avian Family

scholarly journals Population genomics of parallel phenotypic evolution in stickleback across stream–lake ecological transitions

2011 ◽  
Vol 279 (1732) ◽  
pp. 1277-1286 ◽  
Author(s):  
Bruce E. Deagle ◽  
Felicity C. Jones ◽  
Yingguang F. Chan ◽  
Devin M. Absher ◽  
David M. Kingsley ◽  
...  
Keyword(s):  
Evolutionary Biology ◽  
Population Genomics ◽  
Haida Gwaii ◽  
Single Nucleotide ◽  
Genome Scans ◽  
Genetic Changes ◽  
Genome Wide ◽  
Outlier Loci ◽  
Genomic Regions

Understanding the genetics of adaptation is a central focus in evolutionary biology. Here, we use a population genomics approach to examine striking parallel morphological divergences of parapatric stream–lake ecotypes of threespine stickleback fish in three watersheds on the Haida Gwaii archipelago, western Canada. Genome-wide variation at greater than 1000 single nucleotide polymorphism loci indicate separate origin of giant lake and small-bodied stream fish within each watershed (mean F ST between watersheds = 0.244 and within = 0.114). Genome scans within watersheds identified a total of 21 genomic regions that are highly differentiated between ecotypes and are probably subject to directional selection. Most outliers were watershed-specific, but genomic regions undergoing parallel genetic changes in multiple watersheds were also identified. Interestingly, several of the stream–lake outlier regions match those previously identified in marine–freshwater and benthic–limnetic genome scans, indicating reuse of the same genetic loci in different adaptive scenarios. We also identified multiple new outlier loci, which may contribute to unique aspects of differentiation in stream–lake environments. Overall, our data emphasize the important role of ecological boundaries in driving both local and broadly occurring parallel genetic changes during adaptation.

Quantitative Conditions and Convergent Operations That Are Compatible With the Universe as a Persistent Generator of Successive Simulations

2016 ◽  
Vol 12 (1) ◽  
pp. 4178-4187
Author(s):  
Michael A Persinger ◽  
Stanley A Koren
Keyword(s):  
Structural Organization ◽  
Total Duration ◽  
Human Cognition ◽  
Intrinsic Properties ◽  
Basic Assumptions ◽  
Electron Orbit ◽  
Quantitative Analyses ◽  
Massive Information ◽  
The Universe

                The capacity for computer-like simulations to be generated by massive information processing from electron-spin potentials supports Bostrom’s hypothesis that matter and human cognition might reflect simulations. Quantitative analyses of the basic assumptions indicate the universe may display properties of a simulation where photons behave as pixels and gravitons control the structural organization. The Lorentz solution for the square of the light and entanglement velocities converges with the duration of a single electron orbit that ultimately defines properties of matter. The approximately one trillion potential states within the same space with respect to the final epoch of the universe indicate that a different simulation, each with intrinsic properties, has been and will be generated as a type of tractrix defined by ±2 to 3 days (total duration 5 to 6 days). It may define the causal limits within a simulation. Because of the intrinsic role of photons as the pixel unit, phenomena within which flux densities are enhanced, such as human cognition (particularly dreaming) and the cerebral regions associated with those functions, create the conditions for entanglement or excess correlations between contiguous simulations. The consistent quantitative convergence of operations indicates potential validity for this approach. The emergent solutions offer alternative explanations for the limits of predictions for multivariate phenomena that could be coupled to more distal simulations.

Population Control (Review Article)

1961 ◽  
Vol 1 (3) ◽  
pp. 89-98
Author(s):  
Karol J. Krotki
Keyword(s):  
Population Control ◽  
Review Article ◽  
Small Enterprise ◽  
Opportunity Costs ◽  
Relative Importance ◽  
Factual Information ◽  
Undue Influence ◽  
Clear Cut ◽  
Economic Considerations

Discussions about the role of small enterprise in economic development tend to remain inconclusive partly because of the difficulty of assessing the relative importance of economic and non-economic objectives and partly because of the dearth of factual information on which to base an economic calculus. It is probably true, moreover, that, because of a lack of general agreement as to the economic case for or against small enterprise, non-economic considerations, including some merely romantic attitudes toward smallness and bigness, tend to exert an undue influence on public policies. There may, of course, be no clear-cut economic case. And noneconomic considerations should and will inevitably weigh significantly in policy decisions. If, however, some of the economic questions could be settled by more and better knowledge, these decisions could more accurately reflect the opportunity costs of pursuing non-economic objectives.

scholarly journals Role of propagule pressure in colonization success: disentangling the relative importance of demographic, genetic and habitat effects

2013 ◽  
Vol 26 (8) ◽  
pp. 1691-1699 ◽  
Author(s):  
R. A. Hufbauer ◽  
A. Rutschmann ◽  
B. Serrate ◽  
H. Vermeil de Conchard ◽  
B. Facon
Keyword(s):  
Propagule Pressure ◽  
Relative Importance ◽  
Colonization Success

First record of albino lowland tapirs (Tapirus terrestris Linnaeus 1758) in an important Brazilian Atlantic Forest hotspot

Mammalia ◽  
2020 ◽  
Vol 84 (6) ◽  
pp. 601-604
Author(s):  
Mariana Bueno Landis ◽  
Luciano Candisani ◽  
Leticia Prado Munhoes ◽  
João Carlos Zecchini Gebin ◽  
Frineia Rezende ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Atlantic Forest ◽  
Scientific Research ◽  
First Record ◽  
Brazilian Atlantic Forest ◽  
Tapirus Terrestris

AbstractAlbinism is the absence of pigmentation or coloration and is rarely found in nature. In this study we examined photos and videos obtained by cameras traps in the Legado das Águas Reserve. In the images, we identified two albino lowland tapirs. The results highlight the necessity of understanding the genetic diversity of lowland tapir populations and the important role of the professional photography associated with scientific research.

scholarly journals The Arctic as a “Strategic” and “Important” Chinese Foreign Policy Interest: Exploring the Role of Labels and Hierarchies in China’s Arctic Discourses

2021 ◽  
pp. 186810262110186
Author(s):  
Patrik Andersson
Keyword(s):  
Foreign Policy ◽  
International Relations ◽  
Political Discourse ◽  
Chinese Foreign Policy ◽  
The Arctic ◽  
Relative Importance ◽  
Precise Understanding ◽  
New Frontier ◽  
Political Priority

Research confirms that China is becoming more engaged in the Arctic. However, international relations scholarship often extrapolates from relatively few instances of activity to wide-ranging claims about Chinese priorities. Fortunately, Chinese political discourse is organised by labels that allow us to study how the Arctic is classified and ranked along China’s other foreign policy priorities. This article analyses two such classifications – “important maritime interest” and “strategic new frontier,” exploring how they have come about, what they mean, and how they add political priority to the Arctic. It argues that hierarchies are constructed in two ways: by adding gradients and by including/excluding categories of priority. It views categories as performative: they not only convey information about character and relative importance of interests but are also used for achieving different objectives. By focusing on foreign policy classifications, the article contributes to a more nuanced and precise understanding of China’s Arctic interests.

scholarly journals Identification of Autosomal Regions Involved in Drosophila Raf Function

Genetics ◽  
2000 ◽  
Vol 156 (2) ◽  
pp. 763-774 ◽  
Author(s):  
Willis Li ◽  
Elizabeth Noll ◽  
Norbert Perrimon
Keyword(s):  
Limb Development ◽  
Target Gene ◽  
Biological Function ◽  
Genetic Interaction ◽  
Ectopic Expression ◽  
Tor Signaling ◽  
Downstream Effector ◽  
Early Embryos ◽  
Genomic Regions

Abstract Raf is an essential downstream effector of activated p21Ras (Ras) in transducing proliferation or differentiation signals. Following binding to Ras, Raf is translocated to the plasma membrane, where it is activated by a yet unidentified “Raf activator.” In an attempt to identify the Raf activator or additional molecules involved in the Raf signaling pathway, we conducted a genetic screen to identify genomic regions that are required for the biological function of Drosophila Raf (Draf). We tested a collection of chromosomal deficiencies representing ∼70% of the autosomal euchromatic genomic regions for their abilities to enhance the lethality associated with a hypomorphic viable allele of Draf, DrafSu2. Of the 148 autosomal deficiencies tested, 23 behaved as dominant enhancers of Draf  Su2, causing lethality in Draf  Su2 hemizygous males. Four of these deficiencies identified genes known to be involved in the Drosophila Ras/Raf (Ras1/Draf) pathway: Ras1, rolled (rl, encoding a MAPK), 14-3-3ϵ, and bowel (bowl). Two additional deficiencies removed the Drosophila Tec and Src homologs, Tec29A and Src64B. We demonstrate that Src64B interacts genetically with Draf and that an activated form of Src64B, when overexpressed in early embryos, causes ectopic expression of the Torso (Tor) receptor tyrosine kinase-target gene tailless. In addition, we show that a mutation in Tec29A partially suppresses a gain-of-function mutation in tor. These results suggest that Tec29A and Src64B are involved in Tor signaling, raising the possibility that they function to activate Draf. Finally, we discovered a genetic interaction between Draf  Su2 and Df(3L)vin5 that revealed a novel role of Draf in limb development. We find that loss of Draf activity causes limb defects, including pattern duplications, consistent with a role for Draf in regulation of engrailed (en) expression in imaginal discs.

Study of the role of Chlamydia, Mycoplasma, Ureaplasma and other microaerophilic and aerobic bacteria in uterine infections of mares with reproductive disorders

2003 ◽  
Vol 51 (1) ◽  
pp. 45-52 ◽  
Author(s):  
László Szeredi ◽  
M. Tenk ◽  
I. Schiller ◽  
Keyword(s):  
Pathogenic Bacteria ◽  
Anaerobic Bacteria ◽  
Aerobic Bacteria ◽  
Relative Importance ◽  
Reproductive Disorders ◽  
Taylorella Equigenitalis

In six healthy mares and 24 mares showing reproductive disorders swab samples were taken from the fossa clitoridis to isolate Taylorella equigenitalis, and from the uterus to isolate mycoplasmas, ureaplasmas and other aerobic bacteria. Swab samples were also taken from the uterus for Chlamydiaantigen ELISA and ChlamydiaPCR studies. The uterus of 27 mares was examined cytologically, and biopsy samples were taken from the endometrium for histological examinations and for immunohistochemical examinations aimed at the detection of chlamydiae. T. equigenitalis, mycoplasmas, ureaplasmas and chlamydiae could not be detected from any of the mares examined. Aerobic facultative pathogenic bacteria were isolated from mares with endometritis in four cases. In 18 out of 22 mares with endometritis (82%) no infective agents could be demonstrated. Further studies are needed to elucidate the relative importance of non-infectious causes of endometritis and of anaerobic bacteria often detectable in the uterus in the aetiology of the reproductive disorders observed.

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