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The Henicorhina wood-wren complex consists of three taxonomic species. Two of these, the Gray-breasted Wood-Wren (Henicorhina leucophrys) and the White-breasted Wood-Wren (H. leucosticta), are widespread throughout Central America and northern South America, with leucophrys occurring at higher elevations in regions where both occur. A third, recently described, species--the Bar-winged Wood-Wren (H. leucoptera)--occurs only in several isolated cordilleras in southeastern Ecuador and northeastern Peru, where it replaces the Gray-breasted Wood-Wren at the highest elevations. We used mitochondrial DNA sequences to explore the phylogenetic relationships among populations of these taxa and to draw inferences about the evolutionary origins of elevational zonation. We found substantial mitochondrial diversity within both leucophrys and leucosticta. Differentiation across the Andes in leucophrys was negligible, but populations from Central America and from northwestern Ecuador showed substantial differentiation. Three highly differentiated haplotype groups were also present in leucosticta, corresponding to populations in the eastern Andean lowlands, Central America, and the Choco region of northwestern Ecuador; these populations may each warrant taxonomic species status. Bar-winged haplotypes nested within the mitochondrially diverse leucosticta group, where they were most closely allied to the geographically distant Choco haplotypes. This leucopteraleucosticta affinity is not consistent with previous inferences, based on plumage and behavioral similarities, that grouped leucoptera and leucophrys as sister species. These reconstructions refute the hypothesis that elevational zonation in this clade originated from in situ speciation along an elevational gradient, and instead highlight the role of complex changes in geographic distributions in fostering phylogenetic and ecological diversification. Received 7 October 2003, accepted 22 June 2005. Key words: Andes, Ecuador, elevational speciation, Henicorhina, phylogeny, phylogeography, wood-wren. El complejo de trogloditidos del genero Henicorhina esta compuesto por tres especies. Dos de ellas, H. leucophrys y H. leucosticta, estan ampliamente distribuidas a traves de America Central y el norte de Sur America, y leucophrys se encuentra a mayores elevaciones en las regiones donde se encuentran ambas especies. Una tercera especie recientemente descrita, H. leucoptera, se encuentra solo en varias cordilleras aisladas del sureste de Ecuador y el noreste de Peru donde reemplaza a leucophrys a elevaciones mayores. En este estudio empleamos secuencias de ADN mitocondrial para explorar las relaciones filogeneticas entre poblaciones de estos taxa y para hacer inferencias sobre el origen evolutivo de los reemplazos altitudinales. Encontramos que existe considerable diversidad genetica tanto dentro de leucophrys como dentro de leucosticta. La diferenciacion a lo largo de los Andes en leucophrys es despreciable, pero las poblaciones de America Central y del noroeste de Ecuador estan sustancialmente diferenciadas. Dentro de leucosticta existen tres grupos de haplotipos bien diferenciados, que corresponden a las poblaciones de las tierras bajas del este de los Andes, America Central y la region del Choco en el noroeste de Ecuador; estas tres poblaciones podrian ser consideradas como especies diferentes. Los haplotipos de leucoptera estan anidados dentro del grupo de leucosticta, donde estan mas estrechamente relacionados con los haplotipos geograficamente distantes de la region del Choco. Esta afinidad entre leucoptera y leucosticta no es consistente con las inferencias previas basadas en similitudes en el plumaje y el comportamiento, que habian considerado a leucophrys y leucosticta como especies hermanas. Estas reconstrucciones permiten rechazar la hipotesis de que los reemplazos altitudinales en este clado se originaron luego del desarrollo de procesos de especiacion in situ a lo largo de gradientes de elevacion. En cambio, estas reconstrucciones resaltan el papel de los cambios complejos de las distribuciones geograficas promoviendo la diversificacion filogenetica y ecologica.

Riparian habitats typically support high diversity and density of both plants and animals. With the dramatic loss of riparian habitats, restoring them has become a priority among conservation practitioners. Diversity and density of avian species tend to increase following riparian restoration, but little is known about how restored habitats function to meet particular species' needs. Habitat structure is an important factor affecting species diversity and density and can influence nest-site selection and reproductive success. To evaluate habitat restoration, we examined interactions between habitat structure, nest-site selection, and nesting success in Song Sparrows (Melospiza melodia) nesting in restored, mature, and young naturally regenerating stands of riparian forest. We found that stand types differed markedly in structure, and that habitat structure influenced both nest-site selection and rates of nest loss to predation. Comparison of habitat structure among the three stand types indicated that restored stands offered fewer acceptable nest sites and poorer protection from nest predation. Concordant with those differences in habitat structure, Song Sparrows showed trends toward less density in restored stands than in mature forest, and had poorer nesting success as a result of predation. Received 26 August 1999, accepted 27 November 2000.

Explains the significance of feather sampling in ornithological research. Function in data analysis; Challenge posed by systematic collection of feathers from migratory bird populations; Protocols for the preservation of feather material.