Efeitos do comportamento social de agentes dispersores nos padrões de movimento e deposição de sementes.

Seed dispersal is critical to the maintenance of healthy terrestrial habitats and to the regeneration of degraded habitats. As anthropogenic deforestation, fragmentation, and defaunation continue, animal-mediated seed dispersal mutualisms are likely to be disrupted, with potentially serious consequences for forest dynamics. In this review, we examine the degree to which disperser sociality may influence seed dispersal outcomes. Available data are sparse and suggest that the relationship is complex, but some basic trends do emerge from the work to date. Degree of sociality, or group size, may increase the distance seeds are dispersed but also can lead to increased clumped distributions. Territoriality and the resulting defense of resources are likely to reduce the scale of dispersal and lead to clumped seed distributions. Nesting and mating behaviors such as male display are also likely to lead to more clumped distributions. Clumped deposition can have either positive or negative impacts on seed fate, depending on microsite quality, which can vary greatly. In all cases, however, there are exceptions and caveats and the one clear finding from this review is that more work is needed on this subject. We suggest that comparative studies which assess seed dispersal services offered by closely related, syntopic species that vary in key behavioral parameters will be most enlightening. We also highlight the recent use of molecular markers as a particularly effective tool to infer the dispersal services of given species, and to assess the consequences for genetic structure of the plants they disperse. La dispersión de semillas es un evento importante para el mantenimiento de ecosistemas terrestres saludables y para la regeneración de hábitats degradados. Debido a la continua deforestación, fragmentación y pérdida de fauna silvestre, los mutualismos entre plantas y animales dispersores pueden ser interrumpidos, lo que tendría serias consecuencias para la dinámica del bosque. En esta revisión examinamos el nivel en el que la conducta social de los dispersores puede influenciar los patrones de dispersión de semillas. La información disponible es escasa y sugiere que la relación entre estos es compleja, pero algunos patrones pueden ser identificados. El grado de "sociabilidad" o tamaño de grupo puede aumentar la distancia de dispersión de las semillas pero también la agregación espacial de las semillas dispersadas. Se espera también que la territorialidad y la defensa por los recursos reduzcan la distribución espacial de la dispersión y causen una agregación de las semillas. La anidación y otros comportamientos reproductivos como los despliegues sexuales de los machos, también pueden dar lugar a una dispersión agregada de semillas. La agregación de semillas puede tener efectos positivos o negativos en la sobrevivencia de estas dependiendo de la calidad del micro-hábitat, la cual puede variar en gran manera. No obstante, para todos los casos hay excepciones y problemas y una de las conclusiones de esta revisión es que se necesita trabajar mas sobre este tema. En especial los estudios con marcadores moleculares han sido particularmente útiles en este campo, para inferir como los animales dispersan las semillas y para entender las consecuencias genéticas para las plantas dispersadas. Sugerimos que los estudios comparativos sobre los servicios de dispersión prestados por especies relacionadas y sintópicas que varían en su comportamiento serán particularmente esclarecedores.A dispersão de sementes é crucial para a manutenção dos ecossistemas terrestres e regeneração de áreas degradadas. Com a continuidade de atividades antropogênicas que levem ao desmatamento e consequente fragmentação e defaunamento de florestas tropicais, mutualismos entre plantas e animais dispersores podem ser interrompidos, com sérias consequências para as dinâmicas florestais. Nós examinamos como o comportamento social de agentes dispersores pode influenciar padrões de dispersão de sementes. Dados disponíveis na literatura são esparsos e sugerem que esta é uma relação complexa, porém algumas tendências podem ser identificadas. Sugerimos que o grau de socialidade, ou tamanho de grupo, deve aumentar a distância de dispersão, mas também a agregação espacial das sementes dispersadas. Territorialidade e defesa de recursos podem limitar a escala espacial da dispersão, e também causar agregação das sementes. Nidificação e outros comportamentos reprodutivos tais como apresentações sexuais de machos podem, igualmente, causar distribuição agregada de sementes. Essa distribuição agregada pode ter efeitos positivos ou negativos sobre a sobrevivência das sementes, dependendo da qualidade do micro-habitat onde são depositadas. Para todas as tendências apresentadas existem muitas exceções e problemas, e uma das poucas conclusões claras extraídas desta revisão é de que muito mais estudos são necessários sobre este tema. Em particular, marcadores moleculares têm sido particularmente úteis neste campo, tanto para inferir como animais dispersam sementes, como para entender as consequências genéticas para as plantas dispersadas. Sugerimos que estudos comparativos sobre os serviços de dispersão prestados por espécies proximamente relacionadas e sintópicas, mas divergentes em  comportamentos chave serão especialmente esclarecedores

Avifauna of the Mache Chindul ecological reserve, northwest Ecuador

We report on the avifauna of the 120,000 ha Mache Chindul Ecological Reserve (REMACH), northwest Ecuador. The study area is located in a poorly studied transition zone between three major Neotropical biogeographic regions-the Chocó, Tumbesian, and Tropical Andes-each of which contains exceptional diversity and endemism in birds and other organisms. We collected data from 1998–99 and 2004–11 from the Bilsa Biological Station (a 3500 ha private reserve) and several farms, forest fragments, and communities distributed across the central portion of REMACH using observations (aural and visual), audio recordings, mist netting, point counts and photographs. We recorded 360 species of bird (263 genera, 51 families), including 57 threatened species on the Red List of Ecuador, 14 of which are also globally threatened; 23 ‘restricted range’endemic species (15 Chocó and 8 Tumbesian); and 16 migratory species. We recorded breeding activity for 130 species, and documented two distinctive peaks of reproduction, corresponding to the wet and dry seasons, respectively. Our results suggest that REMACH represents a transition zone between Chocó and Tumbesian biogeographic zones, and as such should be considered a priority for conservation of avifauna and other taxa. Accepted 7 November - Reportamos la avifauna de la Reserva Ecológica Mache Chindul (REMACH) de 120.000 ha al noroeste de Ecuador. El área de estudio se encuentra en una zona de transición poco estudiada entre tres grandes regiones biogeográficas neotropicales – el Chocó, Tumbes y los Andes Tropicales – cada una de las cuales contiene una excepcional diversidad y endemismo de aves y otros organismos. Reunimos datos desde 1998–99 y 2004–11 en la Estación Biológica Bilsa (una reserva privada de 3500 hectáreas), en varias fincas, fragmentos forestales y comunidades distribuidas a través de la parte central de REMACH. En estos sitios utilizamos observaciones (registros auditivos y visuales), grabaciones de audio, redes de niebla, puntos de conteo y fotografías. Se registraron 360 especies de aves (263 géneros, 51 familias), incluyendo 57 especies amenazadas de la Lista Roja de Ecuador, 14 de las cuales también se encuentran amenazadas a nivel mundial; 23 especies endémicas ‘rango restringido’ (15 y 8 Tumbes y Chocó ), y 16 especies migratorias. Se registró evidencia reproductiva en 130 especies, y documentamos dos picos bien definidos de reproducción, los que corresponden a las estaciones seca y lluviosa. Nuestros resultados proponen que REMACH representa una zona importante de transición entre las zonas biogeográficas del Chocó y Tumbes, por lo tal debe ser considerada una prioridad para la conservación de la avifauna y otros taxones

Correlated evolution of distinct signals associated with increased social selection in female white-shouldered fairywrens

Conspicuous female signals have recently received substantial scientific attention, but it remains unclear if their evolution is the result of selection acting on females independently of males or if mutual selection facilitates female change. Species that express female, but not male, phenotypic variation among populations represents a useful opportunity to address this knowledge gap. White-shouldered fairywrens (Malurus alboscapulatus) are tropical songbirds with a well-resolved phylogeny where female, but not male, coloration varies allopatrically across subspecies. We explored how four distinct signaling modalities, each putatively associated with increased social selection, are expressed in two populations that vary in competitive pressure on females. Females in a derived subspecies (M. a. moretoni) have evolved more ornamented plumage and have shorter tails (a signal of social dominance) relative to an ancestral subspecies (M. a. lorentzi) with drab females. In response to simulated territorial intrusions broadcasting female song, both sexes of M. a. moretoni are more aggressive and more coordinated with their mates in both movement and vocalizations. Finally, M. a. moretoni songs are more complex than M. a. lorentzi, but song complexity does not vary between sexes in either population. These results suggest that correlated phenotypic shifts in coloration and tail morphology in females as well as song complexity and aggression in both sexes may have occurred in response to changes in the intensity of social selection pressures. This highlights increased competitive pressures in both sexes can facilitate the evolution of complex multimodal signals

FRUIT REMOVAL BY LARGE AVIAN FRUGIVORES VARIES IN RELATION TO HABITAT QUALITY IN CONTINUOUS NEOTROPICAL RAINFOREST

Abstract ∙ Animal-mediated seed dispersal shapes key ecological processes including seedling recruitment and demography. Anthropogenic activities have substantively impacted tropical habitats, yet the degree of sensitivity exhibited by different frugivores to changes in habitat quality and how this may impact seed dispersal outcomes remains poorly understood. This is particularly true in contexts of low to moderate habitat alteration. To address this knowledge gap, we characterized the diurnal disperser community for an ecologically important canopy palm, Oenocarpus bataua, in continuous forest with differing degrees of human modification in northwest Ecuador. Our specific goal was to assess the degree to which visitation and fruit removal rates vary in relation to fine-scale forest structure. Frugivory and seed dispersal (i.e., removal of fruits with intact seeds) was dominated by three large bird species; smaller birds and some mammals visited fruiting trees but did not substantively contribute to seed dispersal. One of the three effective dispersal agents, the Long-wattled Umbrellabird (Cephalopterus penduliger), an endangered species threatened by habitat loss and degradation, exhibited higher visitation and fruit consumption rates in areas characterized by denser canopies, suggesting preference for foraging in undisturbed habitat. In contrast, two relatively common toucan species, Chocó Toucan (Ramphastos brevis) and Chestnut-mandibled Toucan (R. swainsonii), exhibited no variation in foraging behavior in relation to the habitat metrics we assessed. These findings highlight the degree to which differences in sensitivity to habitat disturbance among frugivore species may impact foraging ecology and suggest that variation in forest structure within continuous forest can impact seed removal and seed dispersal processes.Resumen ∙ La remoción de frutas por aves frugívoras de gran tamaño varía con respecto a la calidad de hábitat en bosques continuos Neotropicales La dispersión de semillas mediada por animales moldea procesos ecológicos claves como la posterior supervivencia y demografía de plántulas. Las actividades antropogénicas han afectado substancialmente los hábitats tropicales, sin embargo, el nivel de sensibilidad que presentan los diferentes frugívoros a cambios en la calidad del hábitat y cómo esto afecta a la dispersión de semillas, sigue siendo poco conocido. Esto es particularmente cierto en un contexto de poca a moderada alteración de hábitat. Para lograr comprender este vacío de conocimiento caracterizamos la comunidad de dispersores diurnos de una palma de dosel de importancia ecológica, Oenocarpus bataua, en bosques continuos con niveles diferentes de afectación humana en el noroccidente del Ecuador. Nuestro objetivo principal era de conocer el nivel en el cual las visitas y las tasas de remoción de frutas varía en relación a la estructura del bosque a escala muy fina. La frugivoría y la dispersión de semillas (es decir remoción de frutos con semillas intactas) fue dominada por tres especies de aves de gran tamaño; las aves más pequeñas y ciertos mamíferos visitaron palmas en fruto pero no contribuyeron substancialmente a la dispersión de semillas. Uno de los tres agentes de dispersión efectiva – el Pájaro Toro (Cephalopterus penduliger), una especie amenazada debido a la pérdida y degradación de su hábitat – realizó un mayor número de visitas y tasa de consumo de frutos en áreas caracterizadas por doseles más densos, lo cual sugiere una preferencia de forrajeo en hábitats no alterados. Por el contrario, dos especies relativamente comunes de tucanes, Tucán del Chocó (Ramphastos brevis) y Tucán de Pico Castaño (R. swainsonii), no presentaron diferencias en el comportamiento de forrajeo con respecto a las métricas de hábitat que nosotros utilizamos. Estos hallazgos resaltan el nivel en el cual diferencias en la sensibilidad a la alteración del hábitat entre especies frugívoras pueden impactar la ecología de forrajeo. Sugiere también que la variación en la estructura del bosque dentro de bosques continuos puede impactar la remoción de semillas y el proceso de dispersión de las mismas

ARTICLE Factors influencing Brown Pelican (Pelecanus occidentalis) foraging movement patterns during the breeding season

Abstract: During the breeding season, seabird foraging behaviors are driven by a combination of individual-and external-based factors. This study evaluated how two individual-based factors (body condition and sex) and two external factors (nest stage and colony size), and their interactions, were related to movement. To do so, we used movement data obtained from 22 GPS-tagequipped Brown Pelicans (Pelecanus occidentalis L., 1766) breeding in the northern Gulf of Mexico. In Brown Pelicans, the postegg-hatching phase imposes increased foraging demands on breeding adults relative to the prehatching phase. This study demonstrates that the progression of the breeding period affects the nature and intensity of the relationship between individualbased factors and movement patterns. In particular, birds in relatively lower condition traveled greater distances during foraging trips during the energetically demanding posthatching phase, but not during the incubation stage. Contrary to many seabird species studied to date, neither colony size nor sex appeared to affect Brown Pelican movement patterns. Our results suggest that nest stage is the most important factor influencing foraging movements, and that it may modulate relationships between condition and movement. More refined measures of body condition and foraging behavior will allow further insights into the movement ecology of this seabird

Sex role similarity and sexual selection predict male and female song elaboration and dimorphism in fairy-wrens

Historically, bird song complexity was thought to evolve primarily through sexual selection on males; yet, in many species, both sexes sing and selection pressure on both sexes may be broader. Previous research suggests competition for mates and resources during short, synchronous breeding seasons leads to more elaborate male songs at high, temperate latitudes. Furthermore, we expect male–female song structure and elaboration to be more similar at lower, tropical latitudes, where longer breeding seasons and year-round territoriality yield similar social selection pressures in both sexes. However, studies seldom take both types of selective pressures and sexes into account. We examined song in both sexes in 15 populations of nine-fairy- wren species (Maluridae), a Southern Hemisphere clade with female song. We compared song elaboration (in both sexes) and sexual song dimorphism to latitude and life-history variables tied to sexual and social selection pressures and sex roles. Our results suggest that song elaboration evolved in part due to sexual competition in males: male songs were longer than female songs in populations with low male survival and less male provisioning. Also, female songs evolved independently of male songs: female songs were slower paced than male songs, although only in less synchronously breeding populations. We also found male and female songs were more similar when parental care was more equal and when male survival was high, which provides strong evidence that sex role similarity correlates with male–female song similarity. Contrary to Northern Hemisphere latitudinal patterns, male and female songs were more similar at higher, temperate latitudes. These results suggest that selection on song can be sex specific, with male song elaboration favored in contexts with stronger sexual selection. At the same time, selection pressures associated with sex role similarity appear to favor sex role similarity in song structure

How User‐centric Innovation is Affecting Stakeholder Marketing Strategies: Exploratory Findings from the Music Industry

This paper empirically explores how user‐centric innovation (UCI) in the music industry is affecting how key stakeholder groups are approaching and developing their marketing (and associated management) strategies. The three‐stage interview‐based research methodology consisted of 52 semi‐structured in‐depth interviews with UCI experts and artist managers, as well as representatives from major record labels. The findings make four substantial contributions to theory and practice in the interrelated fields of UCI, marketing and the music industry. First, they provide practical and pragmatic insights for industry practitioners on how different UCI marketing approaches are affecting their management strategies. Second, they take steps towards answering many of the identified gaps in research and knowledge relating to the concept of UCI. Third, they present theoretical models as a foundation for which new UCI marketing theory can be built upon. Last, they offer directions for future research to advance our empirical findings.</jats:p

Multiple hypotheses explain variation in extra-pair paternity at different levels in a single bird family

Extra‐pair paternity (EPP), where offspring are sired by a male other than the social male, varies enormously both within and among species. Trying to explain this variation has proved difficult because the majority of the interspecific variation is phylogenetically based. Ideally, variation in EPP should be investigated in closely related species, but clades with sufficient variation are rare. We present a comprehensive multifactorial test to explain variation in EPP among individuals in 20 populations of nine species over 89 years from a single bird family (Maluridae). Females had higher EPP in the presence of more helpers, more neighbours or if paired incestuously. Furthermore, higher EPP occurred in years with many incestuous pairs, populations with many helpers and species with high male density or in which males provide less care. Altogether, these variables accounted for 48% of the total and 89% of the interspecific and interpopulation variation in EPP. These findings indicate why consistent patterns in EPP have been so challenging to detect and suggest that a single predictor is unlikely to account for the enormous variation in EPP across levels of analysis. Nevertheless, it also shows that existing hypotheses can explain the variation in EPP well and that the density of males in particular is a good predictor to explain variation in EPP among species when a large part of the confounding effect of phylogeny is excluded

Age-dependent relationships between multiple sexual pigments and condition in males and females

The reliability of sexual signaling may change across age classes due to shifts in resource allocation patterns. Two contrasting hypotheses exist regarding how the condition dependence of ornaments may shift with age, and both have received empirical support. On one hand, ornaments may more reliably reflect condition and quality in older individuals, because younger individuals of high quality invest in survival over signaling effort. On the other hand, the condition dependence of ornaments may decline with age, if older individuals in poor condition terminally invest in ornaments, or if resource constraints decline with age. Further, the expression and condition dependence of different ornaments may shift with age in unique ways, such that multifaceted sexual displays maintain reliable signaling across age classes. In yellow warblers (Setophaga petechia) of both sexes, we assessed how relationships between carotenoid-and phaeomelanin-based sexual pigmentation, prenesting body reserves, and condition at molt (reflected by growth bars and feather quality) vary across age classes. Melanin coverage correlated with condition at molt across age classes in males and showed high repeatability in both sexes. In contrast, carotenoid saturation increased longitudinally with age in males and correlated with condition at molt in different age classes in the 2 sexes. Specifically, carotenoid saturation correlated positively with condition at molt in younger, but not older males, whereas in females, the situation was reversed, with a positive correlation present only in older females. Results suggest that age-dependent signaling may promote maintenance of multifaceted sexual displays and that agedependent signaling dynamics depend on sex. © The Author 2013. Published by Oxford University Press on behalf of the International Society for Behavioral Ecology. All rights reserved