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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.].

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.

The Solomon Islands host a diverse terrestrial vertebrate fauna which has played a formative role in the development of speciation theory. Yet, despite over a century of biological exploration in the region, there are many islands for which we have incomplete knowledge of the vertebrate fauna. In 2019, we spent 20 days on Tetepare Island in the Western Province, Solomon Islands. Tetepare has a long history of conservation action by local communities and it is now the largest uninhabited tropical island in the world. We recorded 57 species of birds, 13 mammals, 5 amphibians, and 21 reptiles. Of these, we documented six species for the first time on Tetepare by western scientists: one frog, three non-avian reptiles, and two mammals. These findings point to a continued need for basic biological inventory work to inform research, local conservation efforts, and to increase published knowledge of the biodiversity in the Solomon Islands. Keywords: amphibians, birds, mammals, Melanesia, squamates, tropical South Pacific, Whitney South Sea Expedition, THE SOLOMON ARCHIPELAGO is a biodiverse region that is well known for its unique composition of terrestrial vertebrates (mammals, squamates, amphibians, and birds). Due in part to its high degree [...]

Biodiversity loss is one major outcome of human-mediated ecosystem disturbance. One way that humans have triggered wildlife declines is by transporting disease-causing agents to remote areas of the world. Amphibians have been hit particularly hard by disease due in part to a globally distributed pathogenic chytrid fungus (Batrachochytrium dendrobatidis [Bd]). Prior research has revealed important insights into the biology and distribution of Bd; however, there are still many outstanding questions in this system. Although we know that there are multiple divergent lineages of Bd that differ in pathogenicity, we know little about how these lineages are distributed around the world and where lineages may be coming into contact. Here, we implement a custom genotyping method for a global set of Bd samples. This method is optimized to amplify and sequence degraded DNA from noninvasive skin swab samples. We describe a divergent lineage of Bd, which we call BdASIA3, that appears to be widespread in Southeast Asia. This lineage co-occurs with the global panzootic lineage (BdGPL) in multiple localities. Additionally, we shed light on the global distribution of BdGPL and highlight the expanded range of another lineage, BdCAPE. Finally, we argue that more monitoring needs to take place where Bd lineages are coming into contact and where we know little about Bd lineage diversity. Monitoring need not use expensive or difficult field techniques but can use archived swab samples to further explore the history-and predict the future impacts-of this devastating pathogen.

Exploitation of different locomotor substrates in different ecological niches has driven the evolution of specialized morphological structures, and similar ecological demands, such as the structure of the microhabitat, often lead to convergent or parallel evolution.The evolution of adhesive toepads in geckos remains understudied because of the paucity of phylogenetically‐informed investigations of candidate clades exhibiting purported incipient expression of these (i.e. species having evolved some, but not all, parts of the complex adhesive system of pad‐bearing geckos).Using Cyrtodactylus, a speciose genus with well‐established ecotypes, we tested the hypothesis that microhabitats that require more climbing will lead to the acquisition of incipient adhesive morphology.We measured subdigital scale area, a proxy for adhesive toepad evolution, and quantified subdigital scale shape for 77 of the 354 described species, including at least one representative of each ecotype.Subdigital scale area increased from terrestrial through generalist and saxicoline (rock‐dwelling) to arboreal ecotypes, with subdigital scale shape evolving from ancestral conditions for padless lizards to lateromedially expanded lamella‐like scales only in the arboreal ecotypes.This significant link between phenotype and environment supports the contention that scansorial, and particularly arboreal, Cyrtodactylus ecotypes have evolved incipiently expressed adhesive toepads. This highlights the suitability of this genus as a model system for studying the ecology and evolution of adhesive toepads as well as being a promising candidate for research on adaptive radiations. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Angel Chua Alcala, a pioneer in community-led marine resource management and a renowned Filipino herpetologist, passed away. Born in 1929 in the Philippines, Alcala developed a deep connection with nature and studied biology, specializing in amphibians and reptiles. He made significant contributions to the study of Philippine amphibians and reptiles, describing over 50 new species. Alcala also played a crucial role in the development of community-led marine resource management, establishing the first Marine Protected Area in 1973. His work has had a lasting impact on the conservation of coral reefs and marine biodiversity in the Philippines, serving as a model for other countries. Alcala's research demonstrated the effectiveness of Marine Protected Areas in restoring biodiversity and enhancing fisheries. He also held government positions, implementing policies to protect the environment while considering the welfare of indigenous people. Alcala's contributions to marine conservation and mentorship of young scientists are widely recognized and appreciated. [Extracted from the article]

We describe a new species of fanged frog (genus Limnonectes) from the foothills of two, inland, south-to-north oriented, parallel mountain ranges of Luzon Island of the northern Philippines. Although the new species broadly co-occurs with its closest relative at numerous localities within the Luzon Pleistocene aggregate island complex faunal region, it can be readily diagnosed from Limnonectes macrocephalus based on its unpigmented (white) ventral surfaces of terminal digital discs, its unexpanded or minimally expanded terminal digital discs, and an allometric growth pattern indicating evidence of sexual dimorphism at a smaller overall body size. The new species, which can also be identified by its divergent 16S ribosomal RNA mitochondrial gene sequence, possesses a curious distribution unlike the range of any Philippine endemic amphibian characterized to date: it is known from nine interior (inland) localities distributed between the two, parallel, south-to-north mountain chains (the Cordillera and Sierra Madre) which characterize mainland Luzon. We interpret the presence of two broadly sympatric, genetically divergent, strongly supported haplotype clades—which correspond to morphologically diagnosable phenotypes, using traditional discrete characters and allometric growth patterns—as prima facia evidence of two, independently evolving evolutionary lineages (species) of giant fanged frogs on Luzon. The description of another new species of large-bodied fanged frog on Luzon from multiple localities in close proximity to the capital city (Manila) emphasizes the degree to which even well-studied larger Philippine landmasses possess unrecognized and overlooked biodiversity. [ABSTRACT FROM AUTHOR]

Simple Summary: The Mongolian racerunner (Eremias argus) is a genetically diverse species with a wide distribution across Northeast Asia. The present study is the first to assess the genetic variation in E. argus across its entire geographic range using newly generated mtDNA cyt b and previously published data. We show the complex genetic pattern of this species, where most genetic divergence is not associated with geographic regions. This pattern is the result of multiple influences–robust dispersal ability resulting from ecological features, anthropogenic influence of translocation, and past climate change. Geographic distance has primarily shaped the genetic structure of the species, as indicated by a strong pattern of isolation by distance across all populations. The population growth of E. argus from the Last Interglacial to the Last Glacial Maximum is likely a consequence of an increase in favorable habitats with mild climates following the development of monsoons in East Asia since the mid-Late Pleistocene. Overall, the population genetic structure of E. argus was likely driven by a combination of climatic and geographic changes rather than direct ice sheet coverage. Our results highlight the importance of combining genetic approaches with environmental data when assessing the impact of Pleistocene climatic oscillations. The Mongolian racerunner, Eremias argus, is a small lizard endemic to Northeast Asia that can serve as an excellent model for investigating how geography and past climate change have jointly influenced the evolution of biodiversity in this region. To elucidate the processes underlying its diversification and demography, we reconstructed the range-wide phylogeographic pattern and evolutionary trajectory, using phylogenetic, population genetic, landscape genetic, Bayesian phylogeographic reconstruction and ecological niche modeling approaches. Phylogenetic analyses of the mtDNA cyt b gene revealed eight lineages that were unbounded by geographic region. The genetic structure of E. argus was mainly determined by geographic distance. Divergence dating indicated that E. argus and E. brenchleyi diverged during the Mid-Pliocene Warm Period. E. argus was estimated to have coalesced at~0.4351 Ma (Marine Isotope Stage 19). Bayesian phylogeographic diffusion analysis revealed out-of-Inner Mongolia and rapid colonization events from the end of the Last Interglacial to the Last Glacial Maximum, which is consistent with the expanded suitable range of the Last Glacial Maximum. Pre-Last Glacial Maximum growth of population is presented for most lineages of E. argus. The Glacial Maximum contraction model and the previous multiple glacial refugia hypotheses are rejected. This may be due to an increase in the amount of climatically favorable habitats in Northeast Asia. Furthermore, E. argus barbouri most likely represents an invalid taxon. The present study is the first to report a range-wide phylogeography of reptiles over such a large region in Northeast Asia. Our results make a significant contribution towards understanding the biogeography of the entire Northeast Asia. [ABSTRACT FROM AUTHOR]