Adaptive processes drive ecomorphological convergent evolution in antwrens (Thamnophilidae)

© 2014 The Author(s). Phylogenetic niche conservatism (PNC) and convergence are contrasting evolutionary patterns that describe phenotypic similarity across independent lineages. Assessing whether and how adaptive processes give origin to these patterns represent a fundamental step toward understanding phenotypic evolution. Phylogenetic model-based approaches offer the opportunity not only to distinguish between PNC and convergence, but also to determine the extent that adaptive processes explain phenotypic similarity. The Myrmotherula complex in the Neotropical family Thamnophilidae is a polyphyletic group of sexually dimorphic small insectivorous forest birds that are relatively homogeneous in size and shape. Here, we integrate a comprehensive species-level molecular phylogeny of the Myrmotherula complex with morphometric and ecological data within a comparative framework to test whether phenotypic similarity is described by a pattern of PNC or convergence, and to identify evolutionary mechanisms underlying body size and shape evolution. We show that antwrens in the Myrmotherula complex represent distantly related clades that exhibit adaptive convergent evolution in body size and divergent evolution in body shape. Phenotypic similarity in the group is primarily driven by their tendency to converge toward smaller body sizes. Differences in body size and shape across lineages are associated to ecological and behavioral factors

Systematics of the obligate ant-following clade of antbirds (Aves: Passeriformes: Thamnophilidae)

© 2014 by the Wilson Ornithological Society. Results of a comprehensive molecular phylogeny of the family Thamnophilidae were consistent with earlier findings that almost all obligate army-ant-followers of the family form a monophyletic group that contains five well-supported clades and encompasses six currently recognized genera: Phaenostictus, Pithys, Willisornis, Gymnopithys, Rhegmatorhina, and Phlegopsis. A comparative analysis of seven suites of morphological, behavioral, and ecological traits within the context of the phylogeny reinforced the validity of five of these genera, but results for the sixth, Gymnopithys, were internally inconsistent and required the description of a new genus, Oneillornis

Pseudohyphal growth of the emerging pathogen Candida auris is triggered by genotoxic stress through the S phase checkpoint

We are grateful to Arunaloke Chakrabarti, Anuradha Chowdhary, Elizabeth Johnson (PHE), Takashi Kubota, and Shawn Lockhart (CDC) for providing strains. We thank Fei Long for skillful technical assistance. Flow cytometry was performed at the Iain Fraser Cytometry Centre (IFCC), University of Aberdeen (Raif Yuecel). Microscopy was done at the Microscopy & Histology Facility, University of Aberdeen (Kevin S. Mackenzie). This work was supported by a Wellcome Trust Seed Award to AL [grant number 212524/Z/18/Z], and the Medical Research Council (MRC) Centre for Medical Mycology at the University of Exeter [grant numbers MR/P501955/1, MR/N006364/1].Peer reviewedPreprin

A phylogenetic approach to disentangling the role of competition and habitat filtering in community assembly of Neotropical forest birds

Methods that assess patterns of phylogenetic relatedness, as well as character distribution and evolution, allow one to infer the ecological processes involved in community assembly. Assuming niche conservatism, assemblages should shift from phylogenetic clustering to evenness with decreasing geographic scale because the relative importance of mechanisms that shape assemblages is hypothesized to be scale-dependent. Whereas habitat filtering is more likely to act at regional scales because of increased habitat heterogeneity that allows sorting of ecologically similar species in contrasting environments, competition is more likely to act at local scales because low habitat heterogeneity provides few opportunities for niche partitioning. We used species lists to assess assemblage composition, data on ecologically-relevant traits, and a molecular phylogeny, to examine the phylogenetic structure of antbird (Thamnophilidae) assemblages at three different geographical scales: regional (ecoregions), intermediate (100-ha plots) and local (mixed-flocks). In addition, we used patterns of phylogenetic beta diversity and beta diversity to separate the factors that structure antbird assemblages at regional scales. Contrary to previous findings, we found a shift from phylogenetic evenness to clustering with decreasing geographical scale. We argue that this does not reject the hypothesis that habitat filtering is the predominant force in regional community assembly, because analyses of trait evolution and structure indicated a lack of niche conservatism in antbirds. In some cases, phylogenetic evenness at regional scales can be an effect of historical biogeographic processes instead of niche-based processes. However, regional patterns of beta diversity and phylogenetic beta diversity suggested that phylogenetic structure in our study cannot be explained by the history of speciation and dispersal of antbirds, further supporting the habitat-filtering hypothesis. Our analyses suggested that competitive interactions might not play an important role locally, which would provide a plausible explanation for the high alpha diversity of antbirds in Amazonia. Finally, we emphasize the importance of including trait information in studies of phylogenetic community structure to adequately assess the mechanisms that determine species co-existence. © 2010 The Authors. Journal compilation © 2010 British Ecological Society

Corrigendum to “Phylogeography of the Variable Antshrike (Thamnophilus caerulescens), a South American passerine distributed along multiple environmental gradients” [Mol. Phylogenet. Evol. 148 (2020) 106810](S1055790320300828)(10.1016/j.ympev.2020.106810)

© 2020 Elsevier Inc. The authors regret: (a) The information of Table 2 has incorrect values in column 6. The following table has the correct values. (b) Also, there is a minor typo in the section ‘Data accessibility’, in the word: ‘alignmentsare’. The correct words are: ‘alignments are’. The authors would like to apologize for any inconvenience caused

Phylogeography of the Variable Antshrike (Thamnophilus caerulescens), a South American passerine distributed along multiple environmental gradients

© 2020 Elsevier Inc. The Neotropics show a wealth of distributional patterns shared by many co-distributed species. A distinctive pattern is the so-called “circum-Amazonian distribution,” which is observed in species that do not occur in Amazonia but rather along a belt of forested habitats spanning south and east of Amazonia, the Andean foothills, and often into the Venezuelan Coastal Range and the Tepuis. Although this pattern is widespread across animals and plants, its underlying biogeographic mechanisms remain poorly understood. The Variable Antshrike (Thamnophilus caerulescens) is a sexually dimorphic suboscine passerine that exhibits extreme plumage variation and occurs along the southern portion of the circum-Amazonian belt. We describe broad-scale phylogeographic patterns of T. caerulescens and assess its demographic history using DNA sequences from the mitochondrion and ultraconserved elements (UCEs). We identified three genomic clusters: a) northern Atlantic Forest; b) southeastern Cerrado and central-southern Atlantic Forest, and c) Chaco and Andes. Our results were consistent with Pleistocene divergence followed by gene flow, mainly between the latter two clusters. There were no genetic signatures of rapid population expansions or bottlenecks. The population from the northern Atlantic Forest was the most genetically divergent group within the species. The demographic history of T. caerulescens was probably affected by series of humid and dry periods throughout the Quaternary that generated subtle population expansions and contractions allowing the intermittent connection of habitats along the circum-Amazonian belt. Recognizing the dynamic history of climate-mediated forest expansions, contractions, and connections during the South American Pleistocene is central toward a mechanistic understanding of circum-Amazonian distributions

Rainy cycles in South America as a driver for the breeding of the Black Skimmer (Rynchops niger) and the Large-billed Tern (Phaetusa simplex) (Aves, Charadriiformes)

The Black Skimmer (Rynchops niger) and the Large-billed Tern (Phaetusa simplex) are two migratory waterbirds that breed simultaneously on many river beaches in South America. Both are polytypic taxa with little information about the distribution and nonbreeding (“wintering”) areas. Based on data from the literature, citizen science websites, fieldwork, and specimens housed in natural history museums, we revised the distribution of some of the main breeding colonies in South America, comparing it with continental rainy cycles to identify generalities about the role of precipitation seasonality on the defining intratropical migration routes of these species. Our data suggest that the seasonal precipitation cycle of South America directly influences the reproductive timing and distribution of both species, which is largely circumscribed by South America’s rivers. After breeding on sandy beaches during the dry season, both species disperse in small groups or even individually – not in large flocks as seen in breeding areas – making it difficult to find general migration patterns during the rainy season. Nonetheless, individuals of both species tend to follow the course of the largest rivers of the continent and even alternative routes to disperse into several areas throughout South America during the nonbreeding season

Editorial: Obesogenic Environmental Conditions Affect Neurodevelopment and Neurodegeneration

Editorial on the Research Topic. Obesogenic Environmental Conditions Affect Neurodevelopment and Neurodegeneratio

Utilización de inmunoreacciones para la detección de Scrapie en Óbex de ovinos provenientes de la XII Región de Chile

Scrapie is an neurodegenerative and infectious disease that affects sheep and goats. The purpose of this study is to compare both tecniques, ELISA and IHC, to determine the application factibility giving the conditions of the laboratory in the country. To develop this assay, fourty obex samples were taken from sheep of the XII Region of Chile and were processed for both techniques ELISA and IHC. The results showed 100% of the samples negative for Scrapie, using both diagnostic methods. Based in obtained and previously reported results, ELISA technique can be recommended to use in massive screening, since yields reliable and rapid test results and IHC is a confirmatory technique. Both techniques are necessary in the creation of current epidemiological surveillance programs in Chile. ELISA and IHC are easily performed given the current laboratories conditions of the Chilean country.    El Scrapie es una enfermedad infecciosa neurodegenerativa que afecta a ovinos y caprinos. Dada la importancia que tiene esta enfermedad es que se desarrolló este estudio enmarcado en la comparación de la técnica de ELISA y la de inmunohistoquímica en el diagnóstico de Scrapie, para determinar la factibilidad de aplicarlas en las condiciones de laboratorio país. Para ello se procesaron 40 muestras de óbex de ovinos en duplicado, provenientes de la XII Región de Chile, las cuales fueron sometidas paralelamente a la técnica de ELISA e IHQ. Como resultados se obtuvo un 100% de muestras negativas a Scrapie, sometidas a ambos métodos diagnósticos. Con los valores informados previamente y los obtenidos en esta investigación, es posible recomendar el ELISA como una técnica utilizable en muestreos masivos, ya que aporta resultados confiables de manera más rápida. La IHQ corresponde a una técnica confirmatoria y que ambas, son necesarias en la creación de programas de vigilancia epidemiológica activa en Chile, siendo factibles de realizar en las actuales condiciones de laboratorio país.