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As a dispersive lineage expands its distribution across a heterogeneous landscape, it leaves behind allopatric populations with varying degrees of geographic isolation that often differentiate rapidly. In the case of oceanic islands, even narrowly separated populations often differentiate, which seems contrary to the highly dispersive nature of the founding lineage. This pattern of highly dispersive lineages differentiating across narrow sea barriers has perplexed biologists for more than a century. We used two reduced-representation genomic datasets to examine the diversification of a recent, rapid geographic radiation, the white-eyes (Aves: Zosterops) of the Solomon Islands. We incorporated methods that targeted phylogenetic structure, population structure, and explicit tests for gene flow. Both datasets showed evidence of gene flow among species, but not involving the closely spaced islands in the New Georgia Group. Instead, gene flow has occurred among the larger islands in the archipelago, including those recently connected by land bridges as well as those isolated by large expanses of deep ocean. Populations separated by shallow seas, and connected by land bridges during glacial cycles, ranged from no differentiation to both phenotypic and genomic differentiation. These complex patterns of gene flow and divergence support a model of rapid geographic radiation in which lineages differentially evolve dispersal disparity and phenotypic differences.

The diversity of microbial eukaryotes was surveyed by environmental sequencing from tropical lagoon sites of the South Pacific, collected through the American Museum of Natural History (AMNH)'s Explore21 expedition to the Solomon Islands in September 2013. The sampled lagoons presented low nutrient concentrations typical of oligotrophic waters, but contained levels of chlorophyll a, a proxy for phytoplankton biomass, characteristic of meso- to eutrophic waters. Two 18S rDNA hypervariable sites, V4 and V8-V9 regions, were amplified from the total of eight lagoon samples and sequenced on the MiSeq system. After assembly, clustering at 97% similarity, and removal of singletons and chimeras, a total of 2,741 (V4) and 2,606 (V8-V9) operational taxonomic units (OTUs) were identified. Taxonomic annotation of these reads, including phylogeny, was based on a combination of automated pipeline and manual inspection. 18.4% (V4) and 13.8% (V8-V9) of the OTUs could not be assigned to any of the known eukaryotic groups. Of these, we focused on OTUs that were not divergent and possessed multiple sources of evidence for their existence. Phylogenetic analyses of these sequences revealed more than ten branches that might represent new deeply-branching lineages of microbial eukaryotes, currently without any cultured representatives or morphological information. This article is protected by copyright. All rights reserved.

To meet local and global aspirations toward sustainable resource management, we must first understand what success looks like. At global levels, well-being can be narrowly defined, which may clash with local values and cause adverse impacts. Melanesia is home to a complex mosaic of resource management systems, and finding locally appropriate indicators of success poses particular challenges. We propose that biocultural approaches can assist in developing grounded and appropriate well-being indicators. Biocultural approaches frame issues from the perspectives of place-based communities and work with resource users to develop desired outcomes. In doing so, biocultural approaches recognize links between people and the environment and seek to understand feedbacks between social and ecological components. Biocultural approaches may help to improve the fit between local aspirations and national or international actions and can also cocreate knowledge that draws on local knowledge and practice as well as western science. Here, we report on one such approach in Western Province, Solomon Islands, where rural communities are weighing a variety of trade-offs around the use of natural resources. The work encompasses four locations and seeks to define local needs and priorities, develop appropriate local indicators of success, assess indicator baselines, and catalyze appropriate action. Implementation challenges have included scaffolding between local and national levels and the diversity of the four locations. These have, however, been offset by the engaged nature of indicator creation, which assists communities in planning toward action around local definitions of well-being.

Monitoring and evaluation are central to ensuring that innovative, multi-scale, and interdisciplinary approaches to sustainability are effective. The development of relevant indicators for local sustainable management outcomes, and the ability to link these to broader national and international policy targets, are key challenges for resource managers, policymakers, and scientists. Sets of indicators that capture both ecological and social-cultural factors, and the feedbacks between them, can underpin cross-scale linkages that help bridge local and global scale initiatives to increase resilience of both humans and ecosystems. Here we argue that biocultural approaches, in combination with methods for synthesizing across evidence from multiple sources, are critical to developing metrics that facilitate linkages across scales and dimensions. Biocultural approaches explicitly start with and build on local cultural perspectives — encompassing values, knowledges, and needs — and recognize feedbacks between ecosystems and human well-being. Adoption of these approaches can encourage exchange between local and global actors, and facilitate identification of crucial problems and solutions that are missing from many regional and international framings of sustainability. Resource managers, scientists, and policymakers need to be thoughtful about not only what kinds of indicators are measured, but also how indicators are designed, implemented, measured, and ultimately combined to evaluate resource use and well-being. We conclude by providing suggestions for translating between local and global indicator efforts.

We reconstructed the phylogeographic relationships of the Variable Dwarf-Kingfisher (Ceyx lepidus) using DNA sequence data. Maximum likelihood and Bayesian analysis methods were used to reconstruct trees from a multilocus data set of all 15 named subspecies of the Ceyx lepidus species complex. The concatenated data-set length was 2,471 base pairs and included two mitochondrial genes and two noncoding nuclear introns. Support for the monophyly of C. lepidus was equivocal. We instead found support for a clade including all C. lepidus subspecies plus two endemic Philippine taxa: C. argentatus and C. cyanopectus. Relationships among subspecific taxa were not well resolved, and many nodes were collapsed into polytomies suggesting a rapid and widespread colonization. In situ diversification likely played a role in generating current diversity within four archipelagos: the Philippines, Malukus, Bismarcks, and Solomons. Some biogeographic patterns recovered for the Solomon Islands taxa match those seen ...

The independent evolution of similar traits across multiple taxa provides some of the most compelling evidence of natural selection. Little is known, however, about the genetic basis of these convergent or parallel traits: are they mediated by identical or different mutations in the same genes, or unique mutations in different genes? Using a combination of candidate gene and reduced representation genomic sequencing approaches, we explore the genetic basis of and the evolutionary processes that mediate similar plumage colour shared by isolated populations of theMonarcha castaneiventrisflycatcher of the Solomon Islands. A genome-wide association study (GWAS) that explicitly controlled for population structure revealed that mutations in known pigmentation genes are the best predictors of parallel plumage colour. That is, entirely black or melanic birds from one small island share an amino acid substitution in the melanocortin-1 receptor (MC1R), whereas similarly melanic birds from another small island over 100 km away share an amino acid substitution in a predicted binding site of agouti signalling protein (ASIP). A third larger island, which separates the two melanic populations, is inhabited by birds with chestnut bellies that lack the melanicMC1RandASIPallelic variants. FormalFSToutlier tests corroborated the results of the GWAS and suggested that strong, directional selection drives the near fixation of theMC1RandASIPvariants across islands. Our results, therefore, suggest that selection acting on different mutations with large phenotypic effects can drive the evolution of parallel melanism, despite the relatively small population size on islands.

Factors that influence speciation rates among groups of organisms are integral to deciphering macroevolutionary processes; however, they remain poorly understood. Here, we use molecular phylogenetic data and divergence time estimates to reconstruct the pattern and tempo of speciation within a widespread and homogeneous bird family (white-eyes, Zosteropidae) that contains an archetypal “great speciator.” Our analyses show that the majority of this species-rich family constitutes a clade that arose within the last 2 million years, yielding a per-lineage diversification rate among the highest reported for vertebrates (1.95–2.63 species per million years). However, unlike most rapid radiations reported to date, this burst of diversification was not limited in geographic scope, but instead spanned the entire Old World tropics, parts of temperate Asia, and numerous Atlantic, Pacific, and Indian Ocean archipelagos. The tempo and geographic breadth of this rapid radiation defy any single diversification paradigm, but implicate a prominent role for lineage-specific life-history traits (such as rapid evolutionary shifts in dispersal ability) that enabled white-eyes to respond rapidly and persistently to the geographic drivers of diversification.

Changes in mating signals among populations contribute to species formation. Often these signals involve a suite of display traits of different sensory modalities ("multimodal signals"); however, few studies have tested the consequences of multimodal signal divergence with most focusing on only a single divergent signal or suite of signals of the same sensory modality. Populations of the chestnut-bellied flycatcher Monarcha castaneiventris vary in song and plumage color across the Solomon Islands. Using taxidermic mount presentation and song playback experiments, we tested for the relative roles of divergent song and color in homotypic ("same type") recognition between one pair of recently diverged sister taxa (the nominate chestnut-bellied M. c. castaneiventris and the white-capped M. c. richardsii forms). We found that both plumage and song type influenced the intensity of aggressive response by territory-owners, with plumage color playing a stronger role. These results indicate that differences in plumage and song are used in homotypic recognition, suggesting the importance of multimodal signal divergence in the evolution of premating reproductive isolation.

The golden-mangrove whistler complex Pachycephala pectoralis/melanura is, with 66 named populations, described as the most complex avian example of geographic variation in the World. It represents a well-known example of niche differentiation where one species P. pectoralis is found on faunistically rich larger islands (and mainland) and the other P. melanura is confined to adjacent, faunistically poor islets. Except for a comparison of some Solomon Island populations, the relationships among these taxa have not been tested using molecular data. Here we combine a dense taxon sampling (22 populations of 12 named taxa distributed east of New Guinea and in Australia), with molecular data (two nuclear and two mitochondrial markers) to unravel more of the evolutionary history behind the golden whistler complex. In particular we examine relationships between Pachycephala melanura, and the very similar-looking P. citreogaster (Bismarcks Islands) and P. pectoralis (Australia). We demonstrate that a well-supported group of golden whistlers inhabit the Bismarck Islands and that several small islets in the immediate vicinity are inhabited by another monophyletic group consisting of P. melanura, mangrove golden whistler.

Fruit traits that selectively deter vertebrate seed predators without affecting high-quality seed dispersers are said to exhibit directed deterrence. Directed deterrence has been criticized as being unlikely in natural systems, but has rarely been explicitly tested. We evaluated the potential for directed deterrence to explain the double-layered viscous fruit morphology and fruiting phenology of Terminalia impediens, a common canopy tree endemic to New Guinea. The large fleshy fruits of this tree are consumed and dispersed by cassowaries (Casuarius spp.) and are consumed and killed by palm cockatoos (Probosciger aterrimus). Fruit flesh in this tree species appears to function as a deterrent to seed predation by palm cockatoos; the fruits of T. impediens fall to the ground before ripening, and are avoided by palm cockatoos until after the flesh has rotted off the hard nut. We found that palm cockatoos are able to prey upon seeds from fruits without flesh on the forest floor more efficiently than they can consume seeds from unripe fruit still on the trees. Further, through foraging preference tests, we found that palm cockatoos largely ignore seeds within ripe fruit on the ground, but readily eat the seeds when the fruit flesh has been removed. Cassowaries consume the fruit whole, when ripe, and defecate seeds in piles away from parent trees, where seed predation rates are lower. These results challenge the prevailing view that fleshy fruits evolved in tight synchrony with high-quality seed dispersers and add support to the non-exclusive hypothesis that aspects of fruit fleshiness may also have evolved as a response to seed predation.

We describe the rules of primary flight-feather replacement for Pelagic Cormorants (Phalacrocorax pelagicus), and contrast the completeness of primary replacement in individuals from Asia and North America. In adult Pelagic Cormorants primary replacement is stepwise, with multiple waves of molt, each initiated at the innermost primary (P1), proceeding simultaneously toward the tip of the wing. Shugart and Rohwer's (1996) ontogenetic model for generating and maintaining stepwise primary replacement depended upon incomplete molts. In each new episode of molt, waves of primary replacement were thought to be initiated at P1 and at each arrested wave that had failed to replace all old feathers in the preceding molt. Because most adult Pelagic Cormorants from North America completely replace their primaries but maintain stepwise primary molts, the latter assumption must be relaxed. In contrast to the present-day situation in North America, Pelagic Cormorants from northeastern Asia have incomplete molts of their primaries, and may be forced to skip breeding in some years to clear their wings of overworn primaries. Young birds from Asia start the replacement of their juvenile primaries later than North American birds and replace more feathers simultaneously. Implicancias de la Muda Primaria Completa e Incompleta en la Historia de Vida de Phalacrocorax pelagicus Resumen. Describimos las reglas de reemplazo de plumas primarias para Phalacrocorax pelagicus y contrastamos la totalización del reemplazo de primarias entre individuos de Asia y América del Norte. En individuos adultos, el reemplazo de primarias ocurre en varias etapas, con múltiples secuencias de muda cada una iniciada en la primaria más interna (P1), procediendo simultáneamente hacia la punta del ala. El modelo ontogenético de Shugart y Rohwer (1996) para la generación y mantenimiento del reemplazo en etapas de las plumas primarias depende de mudas incompletas. Se pensaba que en cada nuevo episodio de muda las secuencias de reemplazo de primarias eran iniciadas en P1 y en cada punto de interrupción de la muda precedente que hubiera impedido el reemplazo de todas las plumas viejas. Debido a que la mayoría de los individuos adultos de P. pelagicus de Norteamérica reeemplazan completamente sus primarias pero aún lo hacen en etapas, la última suposición debe ser re-evaluada. En contraste con la situación actual en Norteamérica, individuos del noreste de Asia tienen mudas incompletas de sus primarias y pueden verse forzados a no reproducirse en algunos años para despojarse de la presencia de primarias desgastadas. Las aves juveniles de Asia comienzan el reemplazo de sus primarias más tarde y reemplazan más plumas simultáneamente que las aves de Norteamérica.

We provide the first comprehensive description of a bird community from a lowland rainforest site on a major island in the Solomon Islands. During two dry season visits (July 1997, June 1998) to the lower Garanga River valley on the island of Isabel, we recorded 65 resident and 6 migrant species of birds. We document relative abundances, habitat preferences, and foraging guilds for the members of the bird community. The Garanga River site sustains all but 11 of the 76 species of landbirds known from Isabel. Of those 11 species, four are small-island or beach specialists, three are montane, and four are of unknown status. Habitat heterogeneity, maintained largely by river dynamics, is a major contributor to avian diversity at the site. The avifauna is dominated by nonpasserines, especially parrots, pigeons, kingfishers, and hawks. The flightless rail Nesoclopeus woodfordi, previously regarded as rare and threatened with extinction, was common. We recorded Ixobrychus flavicollis, Falco severus, and Eudynamys scolopacea for the first time on Isabel. We also documented occurrence in the lowlands of Micropsitta finschii, Collocalia spodiopygia, Coracina caledonica, and Pachycephala pectoralis, four species previously thought to be confined to upper elevations on Isabel. The depauperate understory avifauna of the Garanga River site may be anthropogenic and could belie what otherwise seems to be an intact avifauna.

We examine the validity of Phalacrocorax [Stictocarbo] kenyoni, which was described by Siegel-Causey (1991) from the Aleutian Islands using midden remains and existing skeletal specimens. We emphasize a morphometric evaluation of the taxon using 224 skeletal specimens of North Pacific cormorants, but we also evaluate the qualitative characters originally used to characterize P. kenyoni. Principal components and discriminant function analyses of 14 skeletal characters failed to support the validity of the species. Similarly, all seven of the character states that Seigel-Causey described as unique to P. kenyoni also were found in P. pelagicus and P. urile. Thus, the three type specimens of P. kenyoni appear to be P. pelagicus. Although we could not confirm the validity of P. kenyoni, our morphometric analyses revealed that P. pelagicus individuals from the central Aleutians are smaller than those from surrounding populations.

Guided by deeply held cultural values, First Nations in Canada are rapidly regaining legal authority to manage natural resources. We present a research collaboration among academics, tribal government, provincial and federal government, resource managers, conservation practitioners, and community leaders supporting First Nation resource authority and stewardship. First, we present results from a molecular genetics study of grizzly bears inhabiting an important conservation area within the territory of the Heiltsuk First Nation in coastal British Columbia. Noninvasive hair sampling occurred between 2006 and 2009 in the Koeye watershed, a stronghold for grizzly bears, salmon, and Heiltsuk people. Molecular demographic analyses revealed a regionally significant population of bears, which congregate at the Koeye each salmon-spawning season. There was a minimum of 57 individual bears detected during the study period. Results also pointed to a larger than expected source geography for salmon-feeding bears in the study area (> 1000 km²), as well as early evidence of a declining trend in the bear population potentially explained by declining salmon numbers. Second, we demonstrate and discuss the power of integrating scientific research with a culturally appropriate research agenda developed by indigenous people. Guided explicitly by principles from Gvi'ilas or customary law, this research methodology is coupled with Heiltsuk culture, enabling results of applied conservation science to involve and resonate with tribal leadership in ways that have eluded previous scientific endeavors. In this context, we discuss the effectiveness of research partnerships that, from the outset, create both scientific programs and integrated communities of action that can implement change. We argue that indigenous resource management requires collaborative approaches like ours, in which science-based management is embedded within a socially and culturally appropriate context. We emerge not only with a set of guiding principles for resource management by the Heiltsuk, but a broadly applicable strategy that fosters intimacy with traditional lands and resources and provides a powerful engine for conservation.

Biologists have long used islands as natural laboratories for understanding the diversification of life. A conclusion from these studies — notably those of Ernst Mayr — is that life on far-flung archipelagos accumulates from a simple one-way flow of colonists from continents to islands. Filardi and Moyle set out to test this assumption by estimating the relationships of a pan-Pacific bird group, the monarch flycatchers that feature in Mayr's work, through space and time. Their molecular phylogenetic data show that the traditional idea of the islands as stepping stones, with species colonizing Australasia by island-hopping their way across the oceans, does not fit the facts. Instead, the diversity of life across the major Pacific archipelagos is the product of a single radiation involving colonization from islands to continents as well as vice versa. Oceanic islands have long served as natural laboratories for understanding the diversification of life1,2,3,4. In particular, the many thousands of islands spanning the tropical Pacific support an unparalleled array of terrestrial communities whose patterns of diversity contributed fundamental insights to the development of classical speciation and biogeographic theory4,5,6,7,8. Much of this work is founded on an assumption derived from traditional taxonomic approaches, namely that faunas on these widely separated archipelagos stem from a simple one-way, downstream flow of colonists from continents to islands2,4. Here we show, with the use of molecular phylogenetic data from one of the original bird families used to justify this assumption, that a diverse array of endemic island genera and species are the product of a single radiation that diversified across all major Pacific archipelagos in a non-stepping-stone fashion, and recently recolonized continental areas. The geographic scope and lineage-specific approach of this study reveal evolutionary patterns long obscured by traditional taxonomic surveys and indicate that widely dispersed archipelagos can be sources of biological diversity.