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En este trabajo documentamos eventos de reproducción de cinco especies de aves de los Andes tropicales de Bolivia y Argentina. Recolectamos observaciones de eventos de nidificación como parte de campañas ornitológicas en áreas de selva tropical. Para cada evento de nidificación reportamos una descripción completa de la localización y estructura del nido, y cuando posible una descripción de los huevosy/o pichones.En el caso de dos especies (Milano Tijereta [Elanoides forficatus] y Arañero Pechinegro [Myioborus miniatus]), presentamos el primer reporte documentado de nidificación para Bolivia. Fil: Cabanne, Gustavo Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; Argentina Fil: Benites, Maria del Pilar. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; Argentina Fil: Kopuchian, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina Fil: Naoki, Kazuya. Universidad Mayor de San Andrés; Bolivia Fil: Gómez, Isabel. Universidad Mayor de San Andrés; Bolivia

Consistent responses by various organisms to common environmental pressures represent strong evidence of natural selection driving geographical variation. According to Bergmann´s and Allen´s rules, animals from colder habitats are larger and have smaller limbs than those from warmer habitats to minimize heat loss. Although evidence supporting both rules in different organisms exists, most studies have considered only elevational or latitudinal temperature gradients. We tested for the effects of temperature associated with both elevation and latitude on body and appendage size of torrent ducks (Merganetta armata), a widespread species in Andean rivers. We found a negative relationship between body size and temperature across latitude consistent with Bergmann´s rule, whereas there was a positive relationship between these variables along replicate elevational gradients at different latitudes. Limb-size variation did not support Allen´s rule along latitude, nor along elevation. Highelevation ducks were smaller and had longer wings than those inhabiting lower elevations within a river. We hypothesize that temperature is likely a major selective pressure acting on morphology across latitudes, although hypoxia or air density may be more important along elevational gradients. We conclude that the effect of temperature on morphology, and hence the likelihood of documenting ecogeographical rules, depends on the environmental context in which temperature variation is examined. Fil: Gutierrez-Pinto, Natalia. Universidad de los Andes. Departamento de Ciencias Biológicas. Laboratorio de Biología Evolutiva de Vertebrados; Colombia Fil: Mccracken, Kevin. University Of Alaska; Estados Unidos Fil: Alza, Luis. University Of Alaska; Estados Unidos Fil: Tubaro, Pablo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales; Argentina Fil: Kopuchian, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales; Argentina Fil: Astié, Andrea Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto Argentino de Investigaciones de Zonas Aridas; Argentina Fil: Cadena, Daniel. Universidad de los Andes. Departamento de Ciencias Biológicas. Laboratorio de Biología Evolutiva de Vertebrados; Colombia

Understanding how genetic and phenotypic differences that arise in geographically isolated populations influence the outcome of secondary contact advances our knowledge of speciation. In the present study, we investigate the secondary contact between divergent lineages of a widespread Neotropical songbird, the Rufous-collared sparrow (Zonotrichia capensis). Zonotrichia capensis is morphologically and behaviourally diverse, and shows a pattern of lineage diversification produced by a Pleistocene expansion and colonization of South America from a probable Central American origin. Consistent with previous results, we find three lineages throughout the species range, showing between 1.5% and 2.5% divergence in mitochondrial control region sequences. These lineages come into secondary contact in the Dominican Republic, La Paz (Bolivia), and North-eastern Argentina. We use DNA microsatellite data to study a broad secondary contact zone in North-eastern Argentina, finding that Bayesian clustering analyses do not assign individuals to their respective mitochondrial lineages. Overall, we did not observe nuclear genetic discontinuities in the study area. We conclude that, if genetic, morphological, and/or cultural differences accumulated among lineages during isolation, they were insufficient to prevent gene flow after secondary contact. Fil: Campagna, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina. Queens University; Canadá Fil: Kopuchian, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina Fil: Tubaro, Pablo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina Fil: Lougheed, Stephen C.. Queens University; Canadá

Hypoxia is a key factor determining survival, and haemoglobins are targets of selection in species native to high-altitude regions. We studied population genetic structure and evaluated evidence for local adaptation in the crested duck (Lophonetta specularioides). Differentiation, gene flow and time since divergence between highland and lowland populations were assessed for three haemoglobin genes (αA, αD, βA) and compared to seven reference loci (six autosomal introns and mtDNA). Four derived amino acid replacements were found in the globin genes that had elevated ΦST values between the Andean highlands and Patagonian lowlands. A single βA-globin polymorphism at a site known to influence O2 affinity was fixed for different alleles in the two populations, whereas three αA- and αD-globin polymorphisms exhibited high heterozygosity in the highlands but not in the lowlands. Coalescent analyses supported restricted gene flow for haemoglobin alleles and mitochondrial DNA but nonzero gene flow for the introns. Simulating genetic data under a drift–migration model of selective neutrality, the βA-globin fell outside the 95% confidence limit of simulated data, suggesting that directional selection is maintaining different variants in the contrasting elevational environments, thereby restricting migration of βA-globin alleles. The αA- and αD-globins, by contrast, did not differ from the simulated values, suggesting that variants in these genes are either selectively neutral, or that the effects of selection could not be differentiated from background levels of population structure and linkage disequilibrium. This study illustrates the combined effects of selection and population history on inferring levels of population divergence for a species distributed across an altitudinal gradient in which selection for hypoxia resistance has likely played an important role. Fil: Bulgarella, Mariana. Massey University; Nueva Zelanda Fil: Peters, Jeffrey L.. Wright State University; Estados Unidos Fil: Kopuchian, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Valqui, Thomas. Museum of Natural Science; Estados Unidos Fil: Wilson, Robert E.. University Of Alaska; Estados Unidos Fil: Mc Cracken, Kevin G.. University Of Alaska; Estados Unidos

The Ticking Doradito (Pseudocolopteryx citreola) was included in P. flaviventris until a recent taxonomic revalidation. The plumages of the two species are virtually indistinguishable and so recording their vocalizations is necessary in order to identify the species with any certainty. In Chile P. citreola is found in the centre of the country and it is a migrant but its winter distribution is unknown. In Argentina the situation is more complicated as it is possible to find this species and P. flaviventris in the same areas. In Argentina P. citreola occurs in the foothills of the Andes from Río Negro to Salta and it even reaches low lying areas in Bolivia. We present the first two recordings of P. citreola vocalizations for the eastern sector of the Southern Cone (one from eastern Entre Ríos and the other from southwestern Buenos Aires province, Argentina, both in November). We comment on potential confusions created by our new data in reference to the distribution of P. flaviventris in the Cisandean region. Possibly our new records of P. citreola records represent a west-east migration pattern. A phonetical comparation and sonograms showing the differences between the song of this species and the other Pseudocolopteryx is presented. The voices of P. citreola resemble those of P. dinellianus and (to a lesser extent) those of P. acutipennis, and are markedly different from those of P. flaviventris. The voices of P. citreola in Salta province, northwestern Argentina, are somewhat different from those elsewhere, and merit further research. Fil: López Lanús, Bernabé. Audiornis Producciones; Argentina Fil: Unterkofler, Darío E.. Aves Argentinas; Argentina Fil: Ornstein, Ulises. Aves Argentinas; Argentina Fil: Güller, Roberto. Aves Argentinas; Argentina Fil: Lejarraga, Reginaldo. No especifica; Fil: Doiny Cabre, Cristobal. No especifica; Fil: Scoffield, Rosemary L.. Refugio de Vida Silvestre Marahué; Argentina Fil: Kopuchian, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina

The White- throated Foliage- gleaner Automolus roraimae has been a subject of taxonomic and nomenclatural debate almost since its description in 1884. Here, we present vocal, syringeal, behavioural and ecological data that lead us to believe that Automolus roraimae is more closely related to species currently included in Syndactyla than to species currently in Automolus Philydor. It is somewhat divergent from Syndactyla with respect to its adult plumage pattern (although more similar in its juvenile plumage), which more closely resembles some Automolus and Anabazenops. Based on all other characters, these plumage similarities appear convergent and not reflective of relationship. We recommend that ‘Automolus’ roraimae be placed in the genus Syndactyla. The name would thus become Syndactyla roraimae (Hellmayr), and we suggest adopting the English name of Tepui Foliage- gleaner. Fil: Zimmer, Kevin J.. Los Angeles County Museum of Natural History; Estados Unidos Fil: Robbins, Mark B.. Kansas State University; Estados Unidos Fil: Kopuchian, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina