Genetic and morphometric divergence of an invasive bird : the introduced house sparrow (Passer domesticus) in Brazil

Introduced species are interesting systems for the study of contemporary evolution in new environments because of their spatial and temporal scales. For this study we had three aims: (i) to determine how genetic diversity and genetic differentiation of introduced populations of the house sparrow (Passer domesticus) in Brazil varies with range expansion, (ii) to determine how genetic diversity and differentiation in Brazil compares to ancestral European populations; and (iii) to determine whether selection or genetic drift has been more influential on phenotypic divergence. We used six microsatellite markers to genotype six populations from Brazil and four populations from Europe. We found slightly reduced levels of genetic diversity in Brazilian compared to native European populations. However, among introduced populations of Brazil, we found no association between genetic diversity and time since introduction. Moreover, overall genetic differentiation among introduced populations was low indicating that the expansion took place from large populations in which genetic drift effects would likely have been weak. We found significant phenotypic divergence among sites in Brazil. Given the absence of a spatial genetic pattern, divergent selection and not genetic drift seems to be the main force behind most of the phenotypic divergence encountered. Unravelling whether microevolution (e.g., allele frequency change), phenotypic plasticity, or both mediated phenotypic divergence is challenging and will require experimental work (e.g., common garden experiments or breeding programs)

Comparative assessment of mortality risk factors between admission and follow-up models among patients hospitalized with COVID-19

Objectives: This study aimed to compare differences in mortality risk factors between admission andfollow-up incorporated models.Methods: A retrospective cohort study of 524 patients with confirmed COVID-19 infection admitted to atertiary medical center in São Paulo, Brazil from 13 March to 30 April 2020. Data were collected onadmission, and the third, eighth and fourteenth days of hospitalization. The hazard ratio (HR) wascalculated and 28-day in-hospital mortality risk factors were compared between admission and follow-up models using a time-dependent Cox regression model.Results: Of 524 patients, 50.4% needed mechanical ventilation. The 28-day mortality rate was 32.8%.Compared with follow-up, admission models under-estimated the mortality HR for peripheral oxygensaturation 100 bpm (1.19 versus 2.04), respiratory rate >24/min (1.01versus 1.82) and mechanical ventilation (1.92 versus 12.93). Low oxygen saturation, higher oxygensupport and more biomarkers–including lactate dehydrogenase, C-reactive protein, neutrophil-lymphocyte ratio, and urea remained associated with mortality after adjustment for clinical factorsat follow-up compared with only urea and oxygen support at admission.Conclusions: The inclusion of follow-up measurements changed mortality hazards of clinical signs andbiomarkers. Low oxygen saturation, higher oxygen support, lactate dehydrogenase, C-reactive protein,neutrophil-lymphocyte ratio, and urea could help with prognosis of patients during follow-up

Speed of exploration and risk-taking behavior are linked to corticosterone titres in zebra finches

The existence of consistent individual differences in behavioral strategies ("personalities" or coping styles) has been reported in several animal species. Recent work in great tits has shown that such traits are heritable and exhibit significant genetic variation. Free-living birds respond to environmental stresses by up-regulating corticosterone production. Behavior during mild stress can occur in accordance to two types of coping styles, i.e. active and passive. Using artificially selected lines of zebra finches that vary in the amount of corticosterone produced in response to a manual restraint stressor we ran three "personality" experiments. We show that birds in the different corticosterone lines differ in their exploratory and risk-taking behaviors. There was an increase in exploratory behavior as corticosterone titre increased but only in the low corticosterone line. Birds in high corticosterone line showed greater risk-taking behavior than birds in the other lines. Thus, in general, higher levels of circulating corticosterone following a mild stress result in greater exploratory behavior and greater risk taking. This study shows that lines of animals selected for endocrine hormonal responses differ in their "coping" styles or "personalities". © 2007 Elsevier Inc. All rights reserved.Link_to_subscribed_fulltex

Buchnera asiatica

<p>The dashed black lines represents the 95% C.I. for the <i>P_ST</i> calculations, while the dashed red line represent the null assumption that <i>c</i> = <i>h²</i>. Results are for female traits that had critical <i>c/h²</i> (the value in which the lower 95% C.I. of <i>P_ST</i> is higher than the upper 95% C.I. of <i>F_ST</i>) lower than 0.5. For values with higher critical value see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0053332#pone.0053332.s002" target="_blank">Fig. S2</a>.</p

Comparison of different genetic diversity estimators: (Na) number of alleles (A); (Ar) allelic richness (B); (Par) private allelic richness (C); and (He) expected heterozygosity (D) from different house sparrow populations.

<p>For Europe –a and USA data from <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0053332#pone.0053332-Schrey1" target="_blank">[24]</a>; data for Finland from <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0053332#pone.0053332-Kekkonen1" target="_blank">[58]</a>; data for France from <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0053332#pone.0053332-Loiseau1" target="_blank">[59]</a>; and data from Brazil and Europe –b where obtained from this study using all six loci (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0053332#pone-0053332-t001" target="_blank">Table 1</a>). Filled circles are introduced populations while open circles are native populations. Not all estimators were available in all the studies.</p

Scatterplots of <i>F_ST</i> pairwise estimates [<b>62</b>] calculated using FSTAT version 2.9.3 [<b>54</b>] against geographical distance in km (log-transformed) for house sparrow populations of Brazil (A); pairwise harmonic mean <i>D_est</i>[<b>63</b>] calculated using SMOGD [<b>64</b>] against geographic distance in km (log-transformed) for house sparrow populations of Brazil (B); and pairwise <i>R_ST</i> calculated using R CALC [<b>66</b>] against geographic distance in km (log-transformed) for house sparrow populations of Brazil (C).

<p>Scatterplots of <i>F_ST</i> pairwise estimates <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0053332#pone.0053332-Weir1" target="_blank">[<b>62</b>]</a> calculated using FSTAT version 2.9.3 <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0053332#pone.0053332-Goudet1" target="_blank">[<b>54</b>]</a> against geographical distance in km (log-transformed) for house sparrow populations of Brazil (A); pairwise harmonic mean <i>D_est</i><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0053332#pone.0053332-Jost1" target="_blank">[<b>63</b>]</a> calculated using SMOGD <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0053332#pone.0053332-Crawford1" target="_blank">[<b>64</b>]</a> against geographic distance in km (log-transformed) for house sparrow populations of Brazil (B); and pairwise <i>R_ST</i> calculated using R CALC <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0053332#pone.0053332-Goodman1" target="_blank">[<b>66</b>]</a> against geographic distance in km (log-transformed) for house sparrow populations of Brazil (C).</p