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The biota of Sulawesi is noted for its high degree of endemism and for its substantial levels of in situ biological diversification. While the island's long period of isolation and dynamic tectonic history have been implicated as drivers of the regional diversification, this has rarely been tested in the context of an explicit geological framework. Here, we provide a tectonically informed biogeographical framework that we use to explore the diversification history of Sulawesi flying lizards (the Draco lineatus Group), a radiation that is endemic to Sulawesi and its surrounding islands. We employ a framework for inferring cryptic speciation that involves phylogeographic and genetic clustering analyses as a means of identifying potential species followed by population demographic assessment of divergence-timing and rates of bi-directional migration as means of confirming lineage independence (and thus species status). Using this approach, phylogenetic and population genetic analyses of mitochondrial sequence data obtained for 613 samples, a 50-SNP data set for 370 samples, and a 1249-locus exon-capture data set for 106 samples indicate that the current taxonomy substantially understates the true number of Sulawesi Draco species, that both cryptic and arrested speciations have taken place, and that ancient hybridization confounds phylogenetic analyses that do not explicitly account for reticulation. The Draco lineatus Group appears to comprise 15 species-9 on Sulawesi proper and 6 on peripheral islands. The common ancestor of this group colonized Sulawesi ~11 Ma when proto-Sulawesi was likely composed of two ancestral islands, and began to radiate ~6 Ma as new islands formed and were colonized via overwater dispersal. The enlargement and amalgamation of many of these proto-islands into modern Sulawesi, especially during the past 3 Ma, set in motion dynamic species interactions as once-isolated lineages came into secondary contact, some of which resulted in lineage merger, and others surviving to the present. [Genomics; Indonesia; introgression; mitochondria; phylogenetics; phylogeography; population genetics; reptiles.].

Herein, we describe a new species of terrestrially-nesting fanged frog from Sulawesi Island, Indonesia. Though male nest attendance and terrestrial egg deposition is known in one other Sulawesi fanged frog (Limnonectes arathooni), the new species exhibits a derived reproductive mode unique to the Sulawesi assemblage; male frogs guard one or more clutches of eggs festooned to leaves or mossy boulders one to two meters above small slow-moving streams, trickles, or seeps. This island endemic has thus far been collected at three sites on Sulawesi: one in the Central Core of the island, and two on the Southwest Peninsula-south of the Tempe Depression (a major biogeographical boundary). The new Limnonectes has the smallest adult body size among its Sulawesi congeners-with a maximum snout-vent length of about 30 millimeters. Beyond its unique reproductive behavior and body size, the species is further diagnosed on the basis of advertisement call and genetic distance from sympatric fanged frogs. The discovery and description of the new species highlights the remarkable reproductive trait diversity that characterizes the Sulawesi fanged frog assemblage despite that most species in this radiation have yet to be formally described.

Cryptogenic species are those whose native and introduced ranges are unknown. The extent and long history of human migration rendered numerous species cryptogenic. Incomplete knowledge regarding the origin and native habitat of a species poses problems for conservation management and may confound ecological and evolutionary studies. The Lesser Antilles pose a particular challenge with regard to cryptogenic species because these islands have been anthropogenically connected since before recorded history. Here, we use population genetic and phylogeographic tools in an attempt to determine the origin of Eleutherodactylus johnstonei, a frog species with a potentially widespread introduced range and whose native range within the Lesser Antilles is unknown. Based on elevated estimates of genetic diversity and within-island geographic structure not present elsewhere in the range, we identify Montserrat as the native island of E. johnstonei. We also document two major clades within E. johnstonei, only one of which is the primary source of introduced populations throughout the Americas. Our results demonstrate the utility of genetic tools for resolving cryptogenic species problems and highlight E. johnstonei as a potential system for understanding differences in invasive potential among sister lineages.

Field biology is an area of research that involves working directly with living organisms in situ through a practice known as "fieldwork." Conducting fieldwork often requires complex logistical planning within multiregional or multinational teams, interacting with local communities at field sites, and collaborative research led by one or a few of the core team members. However, existing power imbalances stemming from geopolitical history, discrimination, and professional position, among other factors, perpetuate inequities when conducting these research endeavors. After reflecting on our own research programs, we propose four general principles to guide equitable, inclusive, ethical, and safe practices in field biology: be collaborative, be respectful, be legal, and be safe. Although many biologists already structure their field programs around these principles or similar values, executing equitable research practices can prove challenging and requires careful consideration, especially by those in positions with relatively greater privilege. Based on experiences and input from a diverse group of global collaborators, we provide suggestions for action-oriented approaches to make field biology more equitable, with particular attention to how those with greater privilege can contribute. While we acknowledge that not all suggestions will be applicable to every institution or program, we hope that they will generate discussions and provide a baseline for training in proactive, equitable fieldwork practices.

Frogs in the family Ranidae are diverse in Asia and are thought to have dispersed to the Sahul Shelf approximately 10 million years ago, where they radiated into more than a dozen species. Ranid species in the intervening oceanic islands of Wallacea, such as Hylarana florensis and H. elberti from the Lesser Sundas and H. moluccana from eastern Wallacea, are assumed to belong to the subgenus Papurana, yet this has not been confirmed with molecular data. We analyzed mitochondrial DNA of Hylarana species from five islands spanning the reported ranges of H. florensis and H. elberti and compared them to confirmed Papurana species and closely related subgenera within Hylarana. We find that the Lesser Sunda H. florensis and H. elberti form a clade that is sister to the rest of the Australo-Papuan Papurana assemblage. Species delimitation analyses and divergence time estimates suggest that populations of H. florensis on Lombok may be distinct from those on Flores at the species level. Likewise, populations of H. elberti on Sumba and Timor may be distinct from each other and from those on Wetar, tshe type locality of H. elberti. Samples from Babar Island thought to be members of H. elberti in fact belong to the wide-ranging H. daemeli, which occurs in northern Australia, across New Guinea, and on the neighboring island of Tanimbar. These results suggest that the Lesser Sundas may have served as a stepping-stone for colonization of the Sahul Shelf and that species diversity of Papurana frogs is underestimated in the Lesser Sundas.

Background and objectives: African American (AA) children with focal segmental glomerulosclerosis (FSGS) have later onset disease that progresses more rapidly than in non-AA children. It is unclear how APOL1 genotypes contribute to kidney disease risk, progression and cardiovascular morbidity in children. Design, setting, participants, & measurements: We examined the prevalence of APOL1 genotypes and associated cardiovascular phenotypes among children with FSGS in the Chronic Kidney Disease in Children (CKiD) study; an ongoing multicenter prospective cohort study of children aged 1-16 years with mild to moderate kidney disease.Results: A total of 140 AA children in the CKiD study were genotyped. HR APOL1 genotypes were present in 24% of AA children (33/140) and were associated with FSGS, p 3 mg/L (33% vs. 15%, p=0.12) and obesity (48% vs. 19%, p=0.01). There were no differences in glomerular filtration rate, hemoglobin, iPTH, or calcium-phosphate product. Conclusions: AA children with HR APOL1 genotype and FSGS have increase prevalence of obesity and LVH despite a later age of FSGS onset, while adjusting for socioeconomic status. Treatment of obesity may be an important component of CKD and LVH management in this population.

The recognition, evaluation, and early treatment of nephrotic syndrome in infants and children originates from physicians dating back to Hippocrates. It took nearly another thousand years before the condition was described for its massive edema requiring treatment with herbs and other remedies. A rich history of observations and interpretations followed over the course of centuries until the recognition of the combination of clinical findings of foamy urine, swelling of the body, and measurements of urinary protein and blood analyses showed the phenotypic characteristics of the syndrome that were eventually linked to the early anatomic descriptions from first kidney autopsies and then renal biopsy analyses. Coincident with these findings were a series of treatment modalities involving the use of natural compounds to a host of immunosuppressive agents that are applied today. With the advent of molecular and precision medicine, the field is poised to make major advances in our understanding and effective treatment of nephrotic syndrome and prevent its long-term sequelae.

Few observations have been made of Aleutian Terns Onychoprion aleuticus outside of summer breeding colonies. We investigateed the nonbreeding distribution of Aleutian Terns by collating published and unpublished records of observations during the migration and wintering periods, and by implementing a geolocator tracking study at the largest known breeding colony in North America (Yakutat, Alaska). We deployed 114 geolocator tags in 2010 and recovered six tags over the course of six years. Using light level data, we conducted spatial analysis of tern migration cycles from 2010 to 2013. Results revealed one of the longest distance terrestrial vertebrate migrations ever recorded, with a one-way migration distance of > 16 000 km between Alaska and the Southeast Asia/Oceania region. We found that core winter ranges occurred in coastal Thailand, the Philippines, three areas within Indonesia, and Papua New Guinea. Five of the six recovered geolocators contained data spanning multiple years and provided evidence of both wintering- and breeding-site fidelity. Our effort to more completely document the extent of the Aleutian Tern winter range is a foundational step toward understanding both the natural history and the ecological stressors that could affect this under-studied, locally-imperiled seabird. [ABSTRACT FROM AUTHOR]

Abstract: We present a novel method of hydrogen production - applicable to gaseous and distillate fuels - that integrates with a gas turbine and has the potential to reduce the cost and energy required for CO2 capture. The Pressure Swing Reformer (PSR) process yields syngas at high efficiency and with the compactness of an autothermal reformer. PSR is a cyclic, reverse-flow reactor that alternates combustion steps to heat the catalyst bed with reforming steps that cool the bed. During these steps the center of the catalyst bed remains at temperatures approaching 1200 ∘C, enabling rapid and high conversion. Heat exchange within the packed-bed results in relatively cool products, resulting in high efficiency. The debits of conventional hydrogen manufacture, such as air separation or high-temperature furnaces, are completely eliminated. As applied to CO2 capture, PSR’s syngas product is shifted and separated to yield hydrogen and a sequesterable CO2 stream. The hydrogen is used to fuel a gas turbine for power generation, and is also used to fuel the PSR. The power turbine is further integrated by borrowing compressed air from the turbine to use as a combustion source within the PSR. Recovering CO2 from high pressure syngas can reduce separation cost, just as in IGCC. But unlike IGCC, PSR is a low-cost reactor system that uses air at the conditions provided by the GT compressor and returns air at conditions appropriate for the expander. Integrated as such, the PSR enables lower cost production of power with CO2 capture. [Copyright &y& Elsevier]