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Natural history museums are vital repositories of specimens, samples and data that inform about the natural world; this Formal Comment revisits a Perspective that advocated for the adoption of compassionate collection practices, querying whether it will ever be possible to completely do away with whole animal specimen collection.

Amphibians are ideal for studying visual system evolution because their biphasic (aquatic and terrestrial) life history and ecological diversity expose them to a broad range of visual conditions. Here, we evaluate signatures of selection on visual opsin genes across Neotropical anurans and focus on three diurnal clades that are well-known for the concurrence of conspicuous colors and chemical defense (i.e., aposematism): poison frogs (Dendrobatidae), Harlequin toads (Bufonidae: Atelopus), and pumpkin toadlets (Brachycephalidae: Brachycephalus). We found evidence of positive selection on 44 amino acid sites in LWS, SWS1, SWS2, and RH1 opsin genes, of which one in LWS and two in RH1 have been previously identified as spectral tuning sites in other vertebrates. Given that anurans have mostly nocturnal habits, the patterns of selection revealed new sites that might be important in spectral tuning for frogs, potentially for adaptation to diurnal habits and for color-based intraspecific communication. Furthermore, we provide evidence that SWS2, normally expressed in rod cells in frogs and some salamanders, has likely been lost in the ancestor of Dendrobatidae, suggesting that under low-light levels, dendrobatids have inferior wavelength discrimination compared to other frogs. This loss might follow the origin of diurnal activity in dendrobatids and could have implications for their behavior. Our analyses show that assessments of opsin diversification in across taxa could expand our understanding of the role of sensory system evolution in ecological adaptation.

Restriction-site-associated DNA sequencing (RADseq) has become an accessible way to obtain genome-wide data in the form of single-nucleotide polymorphisms (SNPs) for phylogenetic inference. Nonetheless, how differences in RADseq methods influence phylogenetic estimation is poorly understood because most comparisons have largely relied on conceptual predictions rather than empirical tests. We examine how differences in ddRAD and 2bRAD data influence phylogenetic estimation in two non-model frog groups. We compare the impact of method choice on phylogenetic information, missing data, and allelic dropout, considering different sequencing depths. Given that researchers must balance input (funding, time) with output (amount and quality of data), we also provide comparisons of laboratory effort, computational time, monetary costs, and the repeatability of library preparation and sequencing. Both 2bRAD and ddRAD methods estimated well-supported trees, even at low sequencing depths, and had comparable amounts of missing data, patterns of allelic dropout, and phylogenetic signal. Compared to ddRAD, 2bRAD produced more repeatable datasets, had simpler laboratory protocols, and had an overall faster bioinformatics assembly. However, many fewer parsimony-informative sites per SNP were obtained from 2bRAD data when using native pipelines, highlighting a need for further investigation into the effects of each pipeline on resulting datasets. Our study underscores the importance of comparing RADseq methods, such as expected results and theoretical performance using empirical datasets, before undertaking costly experiments.

Amphibians are a clade of over 8,400 species that provide unique research opportunities and challenges. With amphibians undergoing severe global declines, we posit that assessing our current understanding of amphibians is imperative. Focusing on the past five years (2016-2020), we examine trends in amphibian research, data, and systematics. New species of amphibians continue to be described at a pace of â 150 per year. Phylogenomic studies are increasing, fueling a growing consensus in the amphibian tree of life. Over 3,000 species of amphibians are now represented by expert-curated accounts or data in AmphibiaWeb, AmphibiaChina, BIOWEB, or the Amphibian Disease Portal. Nevertheless, many species lack basic natural history data (e.g., diet records, morphological measurements, call recordings) and major gaps exist for entire amphibian clades. Genomic resources appear on the cusp of a rapid expansion, but large, repetitive amphibian genomes still pose significant challenges. Conservation continues to be a major focus for amphibian research, and threats cataloged on AmphibiaWeb for 1,261 species highlight the need to address land use change and disease using adaptive management strategies. To further promote amphibian research and conservation, we underscore the importance of database integration and suggest that other understudied or imperiled clades would benefit from similar assessments of existing data.

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.

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The mainly Mesoamerican cane toad, Rhinella horribilis , is the northernmost species in the Rhinella marina species group of giant or cane toads, occupying an extensive range west of the Andean Cordillera from Ecuador north to southern Texas. However, a thorough assessment of geographic variation among R. horribilis populations, and of the phylogenetic relationships of the R. marina species complex, indicates previously unsuspected diversity within this species as currently recognized. Specifically, we evaluated whether toad populations from western Ecuador represent an evolutionary lineage distinct from the rest of R. horribilis based on extensive specimen collections and the combined evidence of mtDNA sequence variation, morphological, bioacoustics, and environmental information. Our results revealed that populations west of the Ecuadorian Andes constitute a well-supported, monophyletic clade that is distinctly different genetically, morphologically, acoustically, and ecologically from a sister taxon composed of R. horribilis populations from Central America and from populations ascribable to R. marina s.s. from the Amazon Basin of Ecuador and other countries. The weight of evidence confirms a new species (R. bella sp. nov.), described here, adding to our understanding of biogeographic relationships in this widespread clade of Neotropical toads. The new species name means 'beautiful' in Latin, in contrast to its sister species, ' horribilis '. In addition, we designate a lectotype for Bufo marinus var. fluminensis to avoid ambiguity in the applicability of that name. [ABSTRACT FROM AUTHOR]

We describe a new species of Centrolene from the Subandean Cordillera of Kutukú in southeastern Ecuador. The new species differs from all other glassfrogs by the combination of the following characters: presence of processes of vomers but without vomerine teeth; humeral spines in males; dorsum green with light green dots and without dark marks; dorsal skin with abundant tubercles; all visceral peritonea translucent (except for pericardium); and small body size (snout-vent length 21.5–21.9 mm in adult males). The new species is sister to Centrolene camposi from the Western Cordillera of the Andes of southwestern Ecuador, and together they form a clade with C. condor from the Subandean Cóndor Cordillera in southeastern Ecuador. Our time tree suggests that the new species originated at the end of the Pliocene. In addition, we present new information for C. zarza, expanding its geographic range across the southeastern Andes and the Kutukú and Cóndor cordilleras, amending its definition and diagnosis, and offering new information on its natural history and extinction risk. We also discuss the taxonomic status of Ecuadorian populations reported as C. huilensis and conclude that they are C. muelleri based on their close phylogenetic relationships and morphological similarity to samples of C. muelleri from Peru. Centrolene huilensis is a valid species and not closely related to C. muelleri. [ABSTRACT FROM AUTHOR]

With up to 137 species worldwide, Myotis ,— a genus of small, insectivorous bats are an example for understanding biogeographic and evolutionary processes such as intercontinental colonization, diversification, speciation, and convergent adaptive evolution. Species limits and associated distributions, however, remain poorly delineated across significant portions of this diverse group and encompassing a vast geographic range. Here, we explore how diversity is partitioned across this radiation with a focus on Neotropical species of Myotis , using a barcoding approach (706 bp of the mitochondrial DNA gene cytochrome-b) that includes 544 individual sequences (116 newly generated sequences and 428 sequences from GenBank, including outgroups). Single-locus molecular barcoding is useful for identifying cryptic diversity and establishing hypotheses that can guide investigations of species boundaries and phylogenetic relationships, an especially important initial step in assessing poorly characterized, diverse clades. The global phylogeny produced from these data is consistent with the hypothesized monophyly of the New World clade and places the evolutionary relationships of Neotropical species of Myotis within the context of the Palearctic and Nearctic clades. We then explore species boundaries for 25 of the 36 nominal species of Neotropical Myotis , using 3 alternative species delimitation approaches (1 distance-based ABGD [Automatic Barcode Gap Discovery]; and 2 coalescent-based mPTP [multi-rate Poisson Tree Processes], GMYC [Generalized Mixed Yule Coalescent] model). The mPTP (n = 29 species) and ABGD (n = 26) approaches inferred different numbers of species than that recognized by current Neotropical Myotis taxonomy, whereas GMYC (n = 25) inferred the same number of species. In addition to the original 36 Neotropical nominal species currently recognized, we suggest that taxonomic revisions are needed to assess whether M. oxyotus gardneri and M. nigricans osculatii should be elevated to the species level and whether M. dinellii is distinct from M. levis. With the 7 potentially cryptic species identified herein that require further study, the number of Neotropical Myotis may approach 45 species. Taken together, our results suggest that rather than a classic example of a temperate radiation, there may be more species of Myotis in the Neotropics than Nearctic, Afrotropic, Indomalayan, and Oceanian Realms, with only the Palearctic region showing higher species richness. [ABSTRACT FROM AUTHOR]