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The radiation of so-called “great speciators” represents a paradox among the myriad of avian radiations endemic to the southwest Pacific. In such radiations, lineages otherwise capable of dispersing across vast distances of open ocean differentiate rapidly and frequently across relatively short geographic barriers. Here, we evaluate the phylogeography of the Rufous Fantail (Rhipidura rufifrons). Although a presumed “great-speciator”, no formal investigations across its range have been performed. Moreover, delimitation of lineages within R. rufifrons, and the biogeographic implications of those relationships, remain unresolved. To investigate whether R. rufifrons represents a great speciator we identified thousands of single nucleotide polymorphisms for 89 individuals, representing 19 described taxa. Analyses recovered 7 divergent lineages and evidence of gene flow between geographically isolated populations. We also found plumage differences to be a poor proxy for evolutionary relationships. Given the relatively recent divergence dates for the clade (1.35–2.31 mya), rapid phenotypic differentiation, and evidence for multiple independent lineages within the species complex, we determine that R. rufifrons possesses the characteristics of a great speciator.

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.

Malawimonadida is a deep-level (arguably "kingdom-scale") lineage of eukaryotes whose phylogenetic affinities are uncertain but of great evolutionary interest, as the group is suspected to branch close to the root of the tree of eukaryotes. Part of the difficulty in placing Malawimonadida phylogenetically is its tiny circumscription: at present, it comprises only two described and one cultured but undescribed species, all of them are freshwater suspension-feeding nanoflagellates. In this study, we cultivated and characterised Imasa heleensis gen. nov., sp. nov. (Imasidae fam. nov.), the first marine malawimonad to be described. Light and electron microscopy observations show that Imasa is largely similar to other malawimonads, but more frequently adheres to the substrate, often by means of a pliable posterior extension. Phylogenetic analyses based on two ribosomal RNA genes and four translated protein-coding genes using three different taxon sets place Imasa as sister to the three freshwater malawimonad strains with strong support. Imasa's mitochondrial genome is circular-mapping and shows a similar gene complement to other known malawimonads. We conclude that Imasa represents an important expansion of the range of taxa available for future evolutionary study.

We reconstruct the phylogeny of imperial pigeons (genus Ducula) using mitochondrial and nuclear sequence data. We evaluate the most likely biogeographic scenario for the evolution of this group that colonized many islands of the Pacific Ocean. The divergence time analysis suggests that the basal divergences within Ducula occurred more recently than in the fruit doves (genus Ptilinopus), a group that is also well diversified in Oceania. The imperial pigeons colonized the Melanesian region several times independently, and the diversification within this region led to several species in sympatry, in particular in the Bismarck archipelago. Central Polynesia was also colonized several times, first by a lineage during the Miocene that led to the large D. latrans, sister to the New Caledonian endemic D. goliath, then more recently by the widespread D. pacifica, during the Pleistocene. The phylogenetic pattern obtained with the extant Ducula species showed that the Eastern Polynesian endemics do not form a monophyletic group, with the Pacific Imperial Pigeon D. pacifica sister species with good support to the Polynesian Imperial Pigeon D. aurorae. However, the impact of recent anthropic extinctions has been important for the imperial pigeons, more than for the smaller fruit doves, suggesting that several Ducula lineages might be missing today.

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.

The term “wilderness” has several dimensions. It is used as a biological descriptor for intact or largely intact areas that have little or no industrial infrastructure and are remote from urban areas. It is also used as a protected area classification for areas corresponding to Category 1b—wilderness areas in IUCN's protected areas classification system. And finally, the term “wilderness” captures human relationships with wild places—from Indigenous Peoples who view wilderness not as a thing apart but as “home” to sacred natural sites to areas where urban populations recreate. Crucially, wilderness areas are not places where people are excluded, but rather places where certain human activities are restricted or not allowed. Wilderness areas around the world are shrinking quickly and are increasingly rare, and conservation of Earth's remaining wilderness is urgently needed: they are indispensable for biodiversity conservation, for climate change mitigation and adaptation, for freshwater quality—and many other ecosystem services—and for the protection of cultural integrity and biocultural landscapes as well as livelihoods.

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.

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.

— We report new observational and specimen data on the avifauna of Kolombangara, Western Province, Solomon Islands. These data, collected from 3–9 October 1974 and 13–21 May 2004, and supplemented with more recent observations, represent the first comprehensive survey of this globally significant island since 1927. All encounters of montane species are reported along with select species accounts for notable lower-elevation species. Numerous observations presented here suggest avifauna even more unique than previously reported. For example, we confirm a probable resident form of Peregrine Falcon (Falco peregrinus) and report the first observations and collected materials for a Blue-faced Parrotfinch (Erythrura trichroa) from Kolombangara. We observed all of the island's high-elevation endemics and found their relative abundances and patterns of occurrence to be consistent with those of an intact montane avifauna. Our findings suggest that despite large-scale modification of lowland habitat, montan...