Behaviour of resampling methods under different weighting schemes, measures and variable resampling strengths

We compared general behaviour trends of resampling methods (bootstrap, bootstrap with Poisson distribution, jackknife, and jackknife with symmetric resampling) and different ways to summarize the results for resampling (absolute frequency, F, and frequency difference, GC¢) for real data sets under variable resampling strengths in three weighting schemes. We propose an equivalence between bootstrap and jackknife in order to make bootstrap variable across different resampling strengths. Specifically, for each method we evaluated the number of spurious groups (groups not present in the strict consensus of the unaltered data set), of real groups, and of inconsistencies in ranking of groups under variable resampling strengths. We found that GC¢ always generated more spurious groups and recovered more groups than F. Bootstrap methods generated more spurious groups than jackknife methods; and jackknife is the method that recovered more real groups. We consistently obtained a higher proportion of spurious groups for GC¢ than for F; and for bootstrap than for jackknife. Finally, we evaluated the ranking of groups under variable resampling strengths qualitatively in the trajectories of ‘‘support’’ against resampling strength, and quantitatively with Kendall coefficient values. We found fewer ranking inconsistencies for GC¢ than for F, and for bootstrap than for jackknife.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; ArgentinaFil: Ramirez, Martin Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentin

First documented record of the Rufous-tailed Attila (Tyrannidae) for Corrientes, Argentina

We report on the capture of an adult male Rufous-tailed Attila (Attila phoenicurus) in Mburucuyá National Park, Corrientes, Argentina. This is not only the first record for this protected area, but also the first record for the province. Records for this species are scarce in Argentina, where it has been registered only in Misiones province. Populations of this species are believed to be declining, and it is considered a ?threatened species? in Argentina. The confirmed presence of the Rufous-tailed Attila in Mburucuyá National Park extends the species´ distribution range farther south than currently known, and implies that this threatened species occurs in at least one large protected area of Argentina.Fil: García, Natalia Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Trujillo Arias, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: 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; ArgentinaFil: Cabanne, Gustavo Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentin

Distribution, comportement migratoire et conservation du Synallaxe de Hudson Asthenes hudsoni (Furnariidae): un spécialiste des prairies de la pampa humide

Hudson’s Canastero, Asthenes hudsoni (Furnariidae) is a secretive passerine from the Rio de la Plata grasslands of South America. It is considered near threatened, but little is known about its distribution and seasonal movements. We performed a thorough revision of historical and recent records of the species and estimated its original and current geographic distribution using niche modeling based on climatic and land cover information. We found that A. hudsoni is not widespread across the Río de la Plata grasslands but mostly restricted to the humid pampas in Argentina, with isolated populations in central Argentina and SE Brazil. Most records north of the humid pampas in Argentina and Uruguay correspond to wintering individuals, revealing that the species is a partial seasonal migrant. Our distribution models indicate that its original area of occupancy may have been reduced by 65% to a current ~50,000 km², with a stronghold in the flooding Pampas in eastern Buenos Aires province. However, because of the specific microhabitat requirements of the species, we suspect that this figure underestimates the extent of appropriate habitat available, and that A. hudsoni could be very close to the threshold of area of occupancy for vulnerable species under IUCN criteria. Further research on habitat requirements, distribution, and population trends are urgently needed.Le Synallaxe de Hudson, Asthenes hudsoni (Furnariidae) est un passereau discret des prairies du Rio de la Plata en Amérique du Sud. Il est considéré comme quasi menacé, mais on sait peu de choses sur sa répartition et ses mouvements saisonniers. Nous avons effectué une révision complète des enregistrements historiques et récents de l'espèce et estimé sa distribution géographique originale et actuelle en utilisant un modèle de niche basé sur des informations climatiques et de couverture terrestre. Nous avons constaté que A. hudsoni n'est pas répandu dans les prairies du Río de la Plata, mais qu'il est surtout limité à la pampa humide en Argentine, avec des populations isolées dans le centre de l'Argentine et le sud-est du Brésil. La plupart des enregistrements au nord de la pampa humide en Argentine et en Uruguay correspondent à des individus hivernants, ce qui révèle que l'espèce est un migrateur saisonnier partiel. Nos modèles de distribution indiquent que sa zone d'occupation initiale pourrait avoir été réduite de 65% pour atteindre actuellement ~50 000 km², avec un bastion dans les pampas inondées de l'est de la province de Buenos Aires. Cependant, en raison des exigences spécifiques de l'espèce en matière de microhabitat, nous soupçonnons que ce chiffre sous-estime l'étendue de l'habitat approprié disponible et que A. hudsoni pourrait être très proche du seuil de la zone d'occupation des espèces vulnérables selon les critères de l'UICN. Il est urgent de poursuivre les recherches sur les exigences en matière d'habitat, la distribution et les tendances de la population.Fil: Claramunt, Santiago. University of Toronto; Canadá. Royal Ontario Museum; CanadáFil: Aldabe, Joaquín. Manomet Center For Conservation Sciences; Uruguay. Universidad de la Republica; UruguayFil: Etchevers, Ismael. Universidad de la Republica; UruguayFil: Di Giacomo, Adrian Santiago. 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; ArgentinaFil: 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; ArgentinaFil: Milensky, Christopher M.. National Museum of Natural History; Estados Unido

First genetic assessment of the level of endemism in the avifauna of the Central Sierras in southern South America

The Andes constitute one of the main factors that have promoted diversification in the Neotropics. However, the role of other highland regions in the southern cone of South America has been barely studied. We analyzed the level of endemism in the avifauna of the Central Sierras in Córdoba, a high region in central Argentina, to evaluate the effect of its geographic isolation from the Andes. There are 11 species with endemic subspecies in this region, all of them described based only on differences in morphology (mainly plumage color) with no genetic evidence. We performed the first genetic analyses of seven of these species using mitochondrial DNA obtained from fresh tissue and toe pad samples. Our results show that for three of these species, Catamenia inornata, Phrygilus unicolor and Cinclodes atacamensis, the population in the Central Sierras is clearly differentiated from those of other regions, and the first two of them also show divergence among Andean subspecies. In the remaining species we found a varying degree of differentiation, ranging from a small divergence in Muscisaxicola rufivertex to the presence of different haplotypes but with an apparent lack of phylogeographic structure in Phrygilus plebejus and Sturnella loyca (being the latter the only species with a continuous distribution between the Central Sierras and the Andes) to haplotype sharing in Asthenes modesta. While further analyses including additional markers, morphological characters and vocalizations are needed, our results show that some of the species that have disjunct distributions, with a population in the Central Sierras isolated geographically from the Andes, possess distinct genetic lineages in the Central Sierras that suggest an evolutionary isolation from other populations. These findings highlight the importance of montane regions in general, and the Central Sierras in particular, as drivers of diversification in the Neotropics.Fil: Bukowski Loináz, María Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Lavinia Oblanca, Pablo Damián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Trujillo Arias, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: 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; ArgentinaFil: Tubaro, Pablo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Lijtmaer, Dario Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentin

The prescence of Pseudocolopteryx citreola in eastern Argentina, with comparisons of voice with other doraditos

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; ArgentinaFil: Unterkofler, Darío E.. Aves Argentinas; ArgentinaFil: Ornstein, Ulises. Aves Argentinas; ArgentinaFil: Güller, Roberto. Aves Argentinas; ArgentinaFil: Lejarraga, Reginaldo. No especifica;Fil: Doiny Cabre, Cristobal. No especifica;Fil: Scoffield, Rosemary L.. Refugio de Vida Silvestre Marahué; ArgentinaFil: 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; Argentin

Una nueva especie de Capuchino (Sporophila: thraupidae) de los Esteros del Iberá, Corrientes, Argentina

Se describe ua nueva especie de ave perteneciente al género Sporophila (Thraupidae), de los Esteros del Iberá, Corrientes, Argentina; a la que se denomina Sporophila iberaensis.Fil: Di Giacomo, Adrian Santiago. 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; ArgentinaFil: 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; Argentin

Taxonomy, vocalisations, syringeal morphology and natural history of Automolus roraimae (Furnariidae)

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 UnidosFil: Robbins, Mark B.. Kansas State University; Estados UnidosFil: 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; Argentin

Intra- and inter-specific vocal variation in three Neotropical cardinalids (Passeriformes: Fringillidae) and its relationship with body mass

The negative relationship between song frequencies and body weight found by Wallschläger in 1980 is well supported by several studies considering a large number of bird species. However, the results obtained when comparing closely related species or at the intra-specific level were contradicting. The present study compares the vocalizations of four closely related species of Neotropical cardinalids, considering their subspecies: Cyanoloxia glaucocaerulea, Cyanocompsa parellina, Cyanocompsa brissonii and Cyanocompsa cyanoides. These species and subspecies differ significantly in their body mass and provide the opportunity to test the hypothesis that heavier groups produce songs with lower frequencies in closely related lineages. We found that emphasized frequency shows a negative correlation with body weight. These results provide support to Wallschläger´s hypothesis both at the intra- and inter-specific levels in members of the Cyanoloxia-Cyanocompsa clade. Note length, note rate and internote interval length also correlated with body mass, the heavier species having longer notes produced at a lower rate and separated by longer intervals. This correlation of temporal variables with body mass suggests that body size could also influence the temporal structure of song.Fil: Tubaro, Pablo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales; ArgentinaFil: García, Natalia Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales; ArgentinaFil: Barreira, Ana Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales; ArgentinaFil: Kopuchian, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales; Argentin

Adaptive modification of tail structure in relation to body mass and buckling in woodcreepers

We assessed the relationship between function and tail structure of woodcreepers (Dendrocolaptidae) and Neotropical ovenbirds (Furnariidae) using a comparative analysis of independent contrasts. Because woodcreepers are scansorial (they use their tail for body support), we predicted that the structure of the rectrix rachis should be reinforced both at the tip and at the base, whereas the nonscansorial Neotropical ovenbirds should lack reinforcement of the rectrix tips. For each species, we measured the length of the rachis of the medial rectrix and its diameter both at the tip and base of the feather. Rachis diameters were positively associated with body mass in both groups as expected if tail structure were a simple allometric product of body size. However, woodcreepers had larger rachis diameters for a given body mass and higher slopes in the allometric regressions than Neotropical ovenbirds. In addition, we found positive relationships between rachis width at both the tip and base of the rectrix and tail length in woodcreepers, but in Neotropical ovenbirds only rachis width at the base was associated with tail length. These results considered together are consistent with the hypothesis that the tip of the woodcreeper tail rachis is adapted to both support body mass and to prevent Euler buckling failure.Fil: Tubaro, Pablo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Lijtmaer, Dario Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Palacios, María Gabriela. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Kopuchian, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentin

Temporal stability and change in a microgeographical pattern of song variation in the rufous-collared sparrow

We studied the pattern of song variation in the rufous-collared sparrow, Zonotrichia capensis, in the 1987 and 2000 breeding seasons in a 7-km 2 area covering open and closed habitats. We measured 14 quantitative song variables over a total of 390 individuals and found consistent differences between habitats in both years. In particular, songs of individuals from closed habitat sites had trills with longer trill intervals and lower frequencies than those of individuals from open habitats. This pattern of variation is interpreted as a song cline that correlates with the environmental gradient. Although this cline was stable in location and shape, it also showed several differences between years. The songs recorded during 2000 had trills with longer trill intervals and lower minimum frequencies than those recorded during 1987. Thus, this study is the first to directly document temporal changes in song variables in a Z. capensis population. This change would be expected if all the habitats studied were more closed in 2000 than in 1987, but we did not find obvious differences in habitat features between seasons. However, this modification of song structure is compatible with alternative explanations, such as subtle differences in habitat characteristics, changes in climatic variables, a delayed effect of a past modification of the environment and neutrality of the change.Fil: Kopuchian, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; ArgentinaFil: Lijtmaer, Dario Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; ArgentinaFil: Tubaro, Pablo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; ArgentinaFil: Handford, Paul. Western University; Canad