The Subantarctic Rayadito (Aphrastura subantarctica), a new bird species on the southernmost islands of the Americas.

We describe a new taxon of terrestrial bird of the genus Aphrastura (rayaditos) inhabiting the Diego Ramírez Archipelago, the southernmost point of the American continent. This archipelago is geographically isolated and lacks terrestrial mammalian predators as well as woody plants, providing a contrasted habitat to the forests inhabited by the other two Aphrastura spp. Individuals of Diego Ramírez differ morphologically from Aphrastura spinicauda, the taxonomic group they were originally attributed to, by their larger beaks, longer tarsi, shorter tails, and larger body mass. These birds move at shorter distances from ground level, and instead of nesting in cavities in trees, they breed in cavities in the ground, reflecting different life-histories. Both taxa are genetically differentiated based on mitochondrial and autosomal markers, with no evidence of current gene flow. Although further research is required to define how far divergence has proceeded along the speciation continuum, we propose A. subantarctica as a new taxonomic unit, given its unique morphological, genetic, and behavioral attributes in a non-forested habitat. The discovery of this endemic passerine highlights the need to monitor and conserve this still-pristine archipelago devoid of exotic species, which is now protected by the recently created Diego Ramírez Islands-Drake Passage Marine Park.

Combining point counts and autonomous recording units improves avian survey efficacy across elevational gradients on two continents.

Accurate biodiversity and population monitoring is a requirement for effective conservation decision making. Survey method bias is therefore a concern, particularly when research programs face logistical and cost limitations.We employed point counts (PCs) and autonomous recording units (ARUs) to survey avian biodiversity within comparable, high elevation, temperate mountain habitats at opposite ends of the Americas: nine mountains in British Columbia (BC), Canada, and 10 in southern Chile. We compared detected species richness against multiyear species inventories and examined method-specific detection probability by family. By incorporating time costs, we assessed the performance and efficiency of single versus combined methods.Species accumulation curves indicate ARUs can capture ~93% of species present in BC but only ~58% in Chile, despite Chilean mountain communities being less diverse. The avian community, rather than landscape composition, appears to drive this dramatic difference. Chilean communities contain less-vocal species, which ARUs missed. Further, 6/13 families in BC were better detected by ARUs, while 11/11 families in Chile were better detected by PCs. Where survey conditions differentially impacted method performance, PCs mostly varied over the morning and with canopy cover in BC, while ARUs mostly varied seasonally in Chile. Within a single year of monitoring, neither method alone was predicted to capture the full avian community, with the exception of ARUs in the alpine and subalpine of BC. PCs contributed little to detected diversity in BC, but including this method resulted in negligible increases in total time costs. Combining PCs with ARUs in Chile significantly increased species detections, again, for little cost.Combined methods were among the most efficient and accurate approaches to capturing diversity. We recommend conducting point counts, while ARUs are being deployed and retrieved in order to capture additional diversity with minimal additional effort and to flag methodological biases using a comparative framework.

Range-wide genetic structure in the thorn-tailed rayadito suggests limited gene flow towards peripheral populations.

Understanding the population genetic consequences of habitat heterogeneity requires assessing whether patterns of gene flow correspond to landscape configuration. Studies of the genetic structure of populations are still scarce for Neotropical forest birds. We assessed range-wide genetic structure and contemporary gene flow in the thorn-tailed rayadito (Aphrastura spinicauda), a passerine bird inhabiting the temperate forests of South America. We used 12 microsatellite loci to genotype 582 individuals from eight localities across a large latitudinal range (30°S-56°S). Using population structure metrics, multivariate analyses, clustering algorithms, and Bayesian methods, we found evidence for moderately low regional genetic structure and reduced gene flow towards the range margins. Genetic differentiation increased with geographic distance, particularly in the southern part of the species' distribution where forests are continuously distributed. Populations in the north seem to experience limited gene flow likely due to forest discontinuity, and may comprise a demographically independent unit. The southernmost population, on the other hand, is genetically depauperate and different from all other populations. Different analytical approaches support the presence of three to five genetic clusters. We hypothesize that the genetic structure of the species follows a hierarchical clustered pattern.

O espaço enquanto lugar da Subjetividade / The space as a place of Subjectivity

O espaço no qual nos movemos cotidianamente parece tão estável e sólido que nos faz esquecer que a forma como vemos o mundo é sempre afetada por aquilo que acreditamos ou sabemos. No entanto, ao determos os olhos sobre alguma coisa, imediatamente a trazemos para perto e nos situamos em relação a ela. Esta constatação motiva nosso estudo sobre a relação entre espaço e subjetividade. Pretendemos mostrar que a noção de Espaço não pode ser reduzida a uma concepção tecno-científica que o toma como algo dissociado da subjetividade. Ao contrário, ele é o lugar de encontro das subjetividades, possibilitado pela expressividade do corpo, no qual se realiza o intercâmbio entre sujeito e mundo.(AU)

The space in which we move them daily, it always seems to present itself in so steady and solid way, that in it makes to forget them that the form as we see the world it is always affected for what we believe or we know. But, when we holding the eyes on something, immediately we bring it stops close, in we relate them with it, in we point out them in presence of it. Our study above the relation among space and subjectivity was motivated by this ascertainment. We intend to show that Space's notion cannot be reduces to a tecno-scientific conception. The space isn't something separate from subjectivity. On the contrary, it is the place of subjectivities meeting that the body expression makes it possible. Is here, in this place that happen subject-world's interchange.(AU)

O espaço enquanto lugar da Subjetividade / The space as a place of Subjectivity

O espaço no qual nos movemos cotidianamente parece tão estável e sólido que nos faz esquecer que a forma como vemos o mundo é sempre afetada por aquilo que acreditamos ou sabemos. No entanto, ao determos os olhos sobre alguma coisa, imediatamente a trazemos para perto e nos situamos em relação a ela. Esta constatação motiva nosso estudo sobre a relação entre espaço e subjetividade. Pretendemos mostrar que a noção de Espaço não pode ser reduzida a uma concepção tecno-científica que o toma como algo dissociado da subjetividade. Ao contrário, ele é o lugar de encontro das subjetividades, possibilitado pela expressividade do corpo, no qual se realiza o intercâmbio entre sujeito e mundo.

The space in which we move them daily, it always seems to present itself in so steady and solid way, that in it makes to forget them that the form as we see the world it is always affected for what we believe or we know. But, when we holding the eyes on something, immediately we bring it stops close, in we relate them with it, in we point out them in presence of it. Our study above the relation among space and subjectivity was motivated by this ascertainment. We intend to show that Space's notion cannot be reduces to a tecno-scientific conception. The space isn't something separate from subjectivity. On the contrary, it is the place of subjectivities meeting that the body expression makes it possible. Is here, in this place that happen subject-world's interchange.