RESUMEN
Puerto Rico harbors a diverse vertebrate fauna with high levels of endemism. However, while several books for vertebrate diversity and local checklists for birds have been published, checklists of amphibians, reptiles, and bats are lacking or nonexistent at both local and regional scales. In this study, we documented the amphibian, reptile, and bat faunas at Mata de Plátano Field Station and Nature Reserve, in Arecibo, Puerto Rico. We document four species of amphibians, seven lizards, three snakes, and nine bats. Despite prior works using samples from this nature reserve, this represents the first vertebrate checklist for the Mata de Plátano Field Station and Nature Reserve. We provide additional natural history observations based on our survey results and highlight the importance of including local and regional checklists of species for downstream research and conservation.
RESUMEN
Understanding and predicting the relationships between genotype and phenotype is often challenging, largely due to the complex nature of eukaryotic gene regulation. A step towards this goal is to map how phenotypic diversity evolves through genomic changes that modify gene regulatory interactions. Using the Prairie Rattlesnake (Crotalus viridis) and related species, we integrate mRNA-seq, proteomic, ATAC-seq and whole-genome resequencing data to understand how specific evolutionary modifications to gene regulatory network components produce differences in venom gene expression. Through comparisons within and between species, we find a remarkably high degree of gene expression and regulatory network variation across even a shallow level of evolutionary divergence. We use these data to test hypotheses about the roles of specific trans-factors and cis-regulatory elements, how these roles may vary across venom genes and gene families, and how variation in regulatory systems drive diversity in venom phenotypes. Our results illustrate that differences in chromatin and genotype at regulatory elements play major roles in modulating expression. However, we also find that enhancer deletions, differences in transcription factor expression, and variation in activity of the insulator protein CTCF also likely impact venom phenotypes. Our findings provide insight into the diversity and gene-specificity of gene regulatory features and highlight the value of comparative studies to link gene regulatory network variation to phenotypic variation.
Asunto(s)
Venenos de Crotálidos , Crotalus , Evolución Molecular , Animales , Crotalus/genética , Venenos de Crotálidos/genética , Redes Reguladoras de Genes , Regulación de la Expresión GénicaRESUMEN
We present genome assemblies for 18 snake species representing 18 families (Serpentes: Caenophidia): Acrochordus granulatus, Aparallactus werneri, Boaedon fuliginosus, Calamaria suluensis, Cerberus rynchops, Grayia smithii, Imantodes cenchoa, Mimophis mahfalensis, Oxyrhabdium leporinum, Pareas carinatus, Psammodynastes pulverulentus, Pseudoxenodon macrops, Pseudoxyrhopus heterurus, Sibynophis collaris, Stegonotus admiraltiensis, Toxicocalamus goodenoughensis, Trimeresurus albolabris, and Tropidonophis doriae. From these new genome assemblies, we extracted thousands of loci commonly used in systematic and phylogenomic studies on snakes, including target-capture datasets composed of UCEs and AHEs, as well as traditional Sanger loci. Phylogenies inferred from the two target-capture loci datasets were identical with each other, and strongly congruent with previously published snake phylogenies. To show additional utility of these non-model genomes for investigative evolutionary research, we mined the genome assemblies of two New Guinea island endemics in our dataset (Stegonotus admiraltiensis and Tropidonophis doriae) for the ATP1a3 gene, a thoroughly researched indicator of resistance to toad toxin ingestion by squamates. We find that both these snakes possess the genotype for toad toxin resistance despite their endemism to New Guinea, a region absent of any toads until the human-mediated introduction of Cane Toads in the 1930s. These species possess identical substitutions that suggest the same bufotoxin resistance as their Australian congenerics (Stegonotus cucullatus and Tropidonophis mairii) which forage on invasive Cane Toads. Herein, we show the utility of short-read high coverage genomes, as well as improving the deficit of available squamate genomes with associated voucher specimens.
RESUMEN
Mental health chatbots (MHCBs) designed to support individuals in coping with mental health issues are rapidly advancing. Currently, these MHCBs are predominantly used in commercial rather than clinical contexts, but this might change soon. The question is whether this use is ethically desirable. This paper addresses a critical yet understudied concern: assuming that MHCBs cannot have genuine emotions, how this assumption may affect psychotherapy, and consequently the quality of treatment outcomes. We argue that if MHCBs lack emotions, they cannot have genuine (affective) empathy or utilise countertransference. Consequently, this gives reason to worry that MHCBs are (a) more liable to harm and (b) less likely to benefit patients than human therapists. We discuss some responses to this worry and conclude that further empirical research is necessary to determine whether these worries are valid. We conclude that, even if these worries are valid, it does not mean that we should never use MHCBs. By discussing the broader ethical debate on the clinical use of chatbots, we point towards how further research can help us establish ethical boundaries for how we should use mental health chatbots.
Asunto(s)
Emociones , Empatía , Psicoterapeutas , Psicoterapia , Humanos , Psicoterapia/ética , Contratransferencia , Trastornos Mentales/terapia , Salud Mental , Adaptación PsicológicaRESUMEN
Divergence dating analyses in systematics provide a framework to develop and test biogeographic hypotheses regarding speciation. However, as molecular datasets grow from multilocus to genomic, sample sizes decrease due to computational burdens, and the testing of fine-scale biogeographic hypotheses becomes difficult. In this study, we use coalescent demographic models to investigate the diversification of poorly known rice paddy snakes from Southeast Asia (Homalopsidae: Hypsiscopus), which have conflicting dates of origin based on previous studies. We use coalescent modeling to test the hypothesis that Hypsiscopus diversified 2.5 mya during the Khorat Plateau uplift in Thailand. Additionally, we use ecological niche analyses to identify potential differences in the niche space of the two most widely distributed species in the past and present. Our results suggest Hypsiscopus diversified ~ 2.4 mya, supporting that the Khorat Plateau may have initiated the diversification of rice paddy snakes. We also find significant niche differentiation and shifts between species of Hypsiscopus, indicating that environmental differences may have sustained differentiation of this genus after the Khorat Plateau uplift. Our study expands on the diversification history of snakes in Southeast Asia, and highlights how results from smaller multilocus datasets can be useful in developing and testing biogeographic hypotheses alongside genomic datasets.
Asunto(s)
Oryza , Filogenia , Ecosistema , Asia Sudoriental , Tailandia , FilogeografíaRESUMEN
In this study, based on morphological and molecular data, a new bush frog species is described from Yunnan, China. Eleven samples of Raorchestesmalipoensissp. nov. were collected from Malipo County, southeastern Yunnan. This species can be distinguished from other congeners by a combination of 13 morphological characters. Phylogenetic analyses based on the 16S rRNA gene indicate that these individuals form a monophyletic group, and genetic divergence between this clade and its closest relatives is higher than 3.1%, which is comparable to the divergence between recognized Raorchestes species. The discovery of this new species suggests that additional extensive surveys in the southeastern Yunnan would yield more amphibian lineages yet unknown to science.
Asunto(s)
Libertad , Autonomía Personal , Humanos , Paternalismo , Personeidad , Filosofía , Ética Médica , ÉticaRESUMEN
Widespread species often harbor unrecognized genetic diversity, and investigating the factors associated with such cryptic variation can help us better understand the forces driving diversification. Here, we identify potential cryptic species based on a comprehensive dataset of COI mitochondrial DNA barcodes from 2,333 individual Panamanian birds across 429 species, representing 391 (59%) of the 659 resident landbird species of the country, as well as opportunistically sampled waterbirds. We complement this dataset with additional publicly available mitochondrial loci, such as ND2 and cytochrome b, obtained from whole mitochondrial genomes from 20 taxa. Using barcode identification numbers (BINs), we find putative cryptic species in 19% of landbird species, highlighting hidden diversity in the relatively well-described avifauna of Panama. Whereas some of these mitochondrial divergence events corresponded with recognized geographic features that likely isolated populations, such as the Cordillera Central highlands, the majority (74%) of lowland splits were between eastern and western populations. The timing of these splits are not temporally coincident across taxa, suggesting that historical events, such as the formation of the Isthmus of Panama and Pleistocene climatic cycles, were not the primary drivers of cryptic diversification. Rather, we observed that forest species, understory species, insectivores, and strongly territorial species-all traits associated with lower dispersal ability-were all more likely to have multiple BINs in Panama, suggesting strong ecological associations with cryptic divergence. Additionally, hand-wing index, a proxy for dispersal capability, was significantly lower in species with multiple BINs, indicating that dispersal ability plays an important role in generating diversity in Neotropical birds. Together, these results underscore the need for evolutionary studies of tropical bird communities to consider ecological factors along with geographic explanations, and that even in areas with well-known avifauna, avian diversity may be substantially underestimated.
Especies extendidas frecuentemente tiene diversidad genética no reconocida, y investigando los factores asociados con esta variación críptica puede ayudarnos a entender las fuerzas que impulsan la diversificación. Aquí, identificamos especies crípticas potenciales basadas en un conjunto de datos de códigos de barras de ADN mitocondrial de 2,333 individuos de aves de Panama en 429 especies, representando 391 (59%) de las 659 especies de aves terrestres residentes del país, además de algunas aves acuáticas muestreada de manera oportunista. Adicionalmente, complementamos estos datos con secuencias mitocondriales disponibles públicamente de otros loci, tal como ND2 o citocroma b, obtenidos de los genomas mitocondriales completos de 20 taxones. Utilizando los números de identificación de código de barras (en ingles: BINs), un sistema taxonómico numérico que proporcina una estimación imparcial de la diversidad potencial a nivel de especie, encontramos especies crípticas putativas en 19% de las especies de aves terrestres, lo que destaca la diversidad oculta en la avifauna bien descrita de Panamá. Aunque algunos de estos eventos de divergencia conciden con características geográficas que probablemente aislaron las poblaciones, la mayoría (74%) de la divergencia en las tierras bajas se encuentra entre las poblaciones orientales y occidentales. El tiempo de esta divergencia no coincidió entre los taxones, sugiriendo que eventos históricos tales como la formación del Istmo de Panamá y los ciclos climáticos del pleistoceno, no fueron los principales impulsores de la especiación. En cambio, observamos asociaciones fuertes entre las características ecológicas y la divergencia mitocondriale: las especies del bosque, sotobosque, con una dieta insectívora, y con territorialidad fuerte mostraton múltiple BINs probables. Adicionalmente, el índice mano-ala, que está asociado a la capacidad de dispersión, fue significativamente menor en las especies con BINs multiples, sugiriendo que la capacidad de dispersión tiene un rol importamente en la generación de la diversidad de las aves neotropicales. Estos resultos demonstran la necesidad de que estudios evolutivos de las comunidades de aves tropicales consideren los factores ecológicos en conjunto con las explicaciones geográficos.
RESUMEN
COVID-19 vaccine uptake among healthcare workers (HCWs) remains of significant public health concern due to the ongoing COVID-19 pandemic. As a result, many healthcare institutions are considering or have implemented COVID-19 vaccine mandates for HCWs. We assess defenses of COVID-19 vaccine mandates for HCWs from both public health and professional ethics perspectives. We consider public health values, professional obligations of HCWs, and the institutional failures in healthcare throughout the COVID-19 pandemic which have impacted the lived experiences of HCWs. We argue that, despite the compelling urgency of maximizing COVID-19 vaccine uptake among HCWs, the ethical case for COVID-19 vaccine mandates for HCWs in the United States is complex, and, under current circumstances, inconclusive. Nevertheless, we recognize that COVID-19 vaccine mandates for HCWs have already been and will continue to be implemented across many healthcare institutions. Given such context, we provide suggestions for implementing COVID-19 vaccine mandates for HCWs.
Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Humanos , Pandemias , Salud Pública , Personal de SaludRESUMEN
BACKGROUND: Slowing climate change is crucial to the future wellbeing of human societies and the greater environment. Current beef production systems in the USA are a major source of negative environmental impacts and raise various animal welfare concerns. Nevertheless, beef production provides a food source high in protein and many nutrients as well as providing employment and income to millions of people. Cattle farming also contributes to individual and community identities and regional food cultures. Novel plant-based meat alternatives have been promoted as technologies that could transform the food system by reducing negative environmental, animal welfare, and health effects of meat production and consumption. Recent studies have conducted static analyses of shifts in diets globally and in the USA, but have not considered how the whole food system would respond to these changes, nor the ethical implications of these responses. We aimed to better explore these dynamics within the US food system and contribute a multiple perspective ethical assessment of plant-based alternatives to beef. METHODS: In this national modelling analysis, we explored multiple ethical perspectives and the implications of the adoption of plant-based alternatives to beef in the USA. We developed USAGE-Food, a modified version of USAGE (a detailed computable general equilibrium model of the US economy), by improving the representation of sector interactions and dependencies, and consumer behaviour to better reflect resource use across the food system and the substitutability of foods within households. We further extended USAGE, by linking estimates of the environmental footprint of US agriculture, to estimate how changes across the agriculture sector could alter the environmental impact of primary food production across the whole sector, not only the beef sector. Using USAGE-Food, we simulated four beef replacement scenarios against a baseline of current beef demand in the USA: BEEF10, in which beef expenditure is replaced by other foods and three scenarios wherein 10%, 30%, or 60% of beef expenditure is replaced by plant-based alternatives. FINDINGS: The adoption of plant-based beef alternatives is likely to reduce the carbon footprint of US food production by 2·5-13·5%, by reducing the number of animals needed for beef production by 2-12 million. Impacts on other dimensions are more ambiguous, as the agricultural workforce and natural resources, such as water and cropland, are reallocated across the food system. The shifting allocation of resources should lead to a more efficient food system, but could facilitate the expansion of other animal value chains (eg, pork and poultry) and increased exports of agricultural products. In aggregate, these changes across the food system would have a small, potentially positive, impact on national gross domestic product. However, they would lead to substantial disruptions within the agricultural economy, with the cattle and beef processing sectors decreasing by 7-45%, challenging the livelihoods of the more than 1·5 million people currently employed in beef value chains (primary production and animal processing) in the USA. INTERPRETATION: Economic modelling suggests that the adoption of plant-based beef alternatives can contribute to reducing greenhouse gas emissions from the food system. Relocation of resources across the food system, simulated by our dynamic modelling approach, might mitigate gains across other environmental dimensions (ie, water or chemical use) and might facilitate the growth of other animal value chains. Although economic consequences at the country level are small, there would be concentrated losses within the beef value chain. Reduced carbon footprint and increased resource use efficiency of the food system are reasons for policy makers to encourage the continued development of these technologies. Despite this positive outcome, policy makers should recognise the ethical assessment of these transitions will be complex, and should remain vigilant to negative outcomes and be prepared to target policies to minimise the worst effects. FUNDING: The Stavros Niarchos Foundation, the Bill & Melinda Gates Foundation, Johns Hopkins University, the Commonwealth Scientific and Industrial Research Organisation, Cornell University, and Victoria University.
Asunto(s)
Dieta , Gases de Efecto Invernadero , Animales , Huella de Carbono , Bovinos , Humanos , Carne , Estados Unidos , AguaRESUMEN
This paper argues that individuals in many high-income countries typically have moral reasons to limit their beef consumption and consume plant-based protein instead, given the negative effects of beef production and consumption. Beef production is a significant source of agricultural greenhouse gas emissions and other environmental impacts, high levels of beef consumption are associated with health risks, and some cattle production systems raise animal welfare concerns. These negative effects matter, from a variety of moral perspectives, and give us collective moral reasons to reduce beef production and consumption. But, as some ethicists have argued, we cannot draw a straight line from the ethics of production to the ethics of consumption: even if a production system is morally impermissible, this does not mean that any given individual has moral reasons to stop consuming the products of that system, given how miniscule one individual's contributions are. This paper considers how to connect those dots. We consider three distinct lines of argument in support of the conclusion that individuals have moral reasons to limit their beef consumption and shift to plant-based protein, and we consider objections to each argument. This argument applies to individuals in high beef-consuming and high greenhouse gas-emitting high-income countries, though we make this argument with a specific focus on the United States. Supplementary Information: The online version contains supplementary material available at 10.1007/s41055-022-00100-8.
RESUMEN
Many phylogeographic studies on species with large ranges have found genetic-geographic structure associated with changes in habitat and physical barriers preventing or reducing gene flow. These interactions with geographic space, contemporary and historical climate, and biogeographic barriers have complex effects on contemporary population genetic structure and processes of speciation. While allopatric speciation at biogeographic barriers is considered the primary mechanism for generating species, more recently it has been shown that parapatric modes of divergence may be equally or even more common. With genomic data and better modeling capabilities, we can more clearly define causes of speciation in relation to biogeography and migration between lineages, the location of hybrid zones with respect to the ecology of parental lineages, and differential introgression of genes between taxa. Here, we examine the origins of three Nearctic milksnakes (Lampropeltis elapsoides, Lampropeltis triangulum and Lampropeltis gentilis) using genome-scale data to better understand species diversification. Results from artificial neural networks show that a mix of a strong biogeographic barrier, environmental changes, and physical space has affected genetic structure in these taxa. These results underscore conspicuous environmental changes that occur as the sister taxa L. triangulum and L. gentilis diverged near the Great Plains into the forested regions of the Eastern Nearctic. This area has been recognized as a region for turnover for many vertebrate species, but as we show here the contemporary boundary does not isolate these sister species. These two species likely formed in the mid-Pleistocene and have remained partially reproductively isolated over much of this time, showing differential introgression of loci. We also demonstrate that when L. triangulum and L. gentilis are each in contact with the much older L. elapsoides, some limited gene flow has occurred. Given the strong agreement between nuclear and mtDNA genomes, along with estimates of ecological niche, we suggest that all three lineages should continue to be recognized as unique species. Furthermore, this work emphasizes the importance of considering complex modes of divergence and differential allelic introgression over a complex landscape when testing mechanisms of speciation. [Cline; delimitation; Eastern Nearctic; Great Plains; hybrids; introgression; speciation.].
Asunto(s)
Colubridae , Flujo Génico , Animales , Especiación Genética , Filogenia , FilogeografíaRESUMEN
Marine mussels have the remarkable ability to adhere to a variety of natural and artificial surfaces under hostile environmental conditions. Although the molecular composition of mussel adhesives has been well studied, a mechanistic understanding of the physical origins of mussels' impressive adhesive strength remains elusive. Here, we investigated the role of substrate geometry in the adhesive performance of mussels. Experimentally, we created substrates with differing surface properties using 3D printing and laser drilling and introduced these to mussels, which in turn adhered to the engineered surfaces via plaque-thread byssal structures. Tensile testing with in situ imaging was conducted to quantify the adhesion strength of the mussel plaques, and the microstructures of the mechanically deformed plaques were characterized using scanning electron microscopy. Our results reveal that the geometry of the surfaces has no significant impact on the detachment force and the strain, whereas the change in adhesion area leads to a different adhesion stress. Ultrastructural analysis confirms the expected presence of an open-cell foamy network coated with the cuticle. The observed detachment dynamics and failure mechanisms do vary depending on the substrate properties, suggesting the presence of substrate-dependent nonuniform stress distributions at the interface. Together, these results show mussels' remarkable ability to adapt to differing physical conditions and demonstrate the importance of the on-demand and in situ manufacturing of the stiff cuticle and relatively compliant adhesive interlayer. The resultant composite structure avoids the formation of prestress during the formation of the adhesive joint, provides conformability to the surface, and helps compensate for local bending interactions to maintain adhesive strength. Our findings suggest forward design strategies to improve adhesive performance on complex surfaces.
Asunto(s)
Bivalvos , Adhesivos , Animales , Fenómenos MecánicosRESUMEN
This article argues that governments in countries that currently permit intensive animal agriculture - especially but not exclusively high-income countries - are, in principle, morally justified in taking steps to restrict or even eliminate intensive animal agriculture to protect public health from the risk of zoonotic pandemics. Unlike many extant arguments for restricting, curtailing, or even eliminating intensive animal agriculture which focus on environmental harms, animal welfare, or the link between animal source food (ASF) consumption and noncommunicable disease, the argument in this article appeals to the value of protecting populations from future global health emergencies and their broad social, economic, and health impacts, taking the SARS-CoV-2 virus as a particularly salient example. The article begins by identifying how intensive animal agriculture contributes to the outbreak (and risk of future outbreaks) of zoonotic diseases. Next, we explore three specific policy options: 1. Incentivizing plant-based and cell-based ASF alternatives through government subsidies; 2. Disincentivizing intensive ASF production through the adoption of a "zoonotic tax"; and 3. Eliminating intensive ASF production through a total ban. We argue that all three of these measures are permissible, although we remain agnostic as to whether these measures are obligatory. We argue for this conclusion on the grounds that each measure is justified by the same sorts of considerations that justify other widely accepted public health interventions, and each is compatible with a variety of theories of justice. We then address potential objections. Finally, we discuss how our novel argument relates to extant ethical arguments in favor or curtailing ASF production and consumption.
RESUMEN
Mud snakes (Serpentes: Homalopsidae) are a family of 55 described, mainly aquatic, species primarily distributed throughout mainland Southeast Asia and the Indo-Australian Archipelago. Although they have been the focus of prior research, the basic relationships amongst genera and species remain poorly known. We used a combined mitochondrial and nuclear gene dataset to infer their phylogenetic relationships, using the highest levels of taxon and geographic sampling for any homalopsid phylogeny to date (62% generic and 62% species coverage; 140 individuals). Our results recover two reciprocally monophyletic groups: the fangless Brachyorrhos and its sister clade comprised of all rear-fanged homalopsids. Most genera and interspecific relationships were monophyletic and strongly supported, but intergeneric relationships and intraspecific population structure lack support. We find evidence of both undescribed diversity as well as cases of taxonomic inflation within several species. Tree-based species delimitation approaches (mPTP) support potential new candidate species as distinct from their conspecifics and also suggest that many named taxa may not be distinct species. Divergence date estimation and lineage-through-time analyses indicate lower levels of speciation in the Eocene, with a subsequent burst in diversification in the Miocene. Homalopsids may have diversified most rapidly during the Pliocene and Pleistocene, possibly in relation to tectonic shifts and sea-level fluctuations that took place in Sundaland and the Sahul Shelf. Our analyses provide new insights on homalopsid taxonomy, a baseline phylogeny for the family, and further biogeographic implications demonstrating how dynamic tectonics and Quaternary sea level changes may have shaped a widespread, diverse family of snakes.
Asunto(s)
Colubridae/clasificación , Filogenia , Filogeografía , Animales , Asia Sudoriental , AustraliaRESUMEN
Cylindrophis is a genus of secretive, semi-fossorial, non-venomous snakes comprising 14 species, characterized by a generally cylindrical body, uniform scales (with barely enlarged ventrals), and vestiges of pelvic and limb bones, the latter terminating in a claw lateral to the vent. We reconstructed a concatenated molecular phylogeny of seven taxa of Cylindrophis taxa based on one nuclear (R35) and two mitochondrial (16S, ND2) genes. Analyses recovered the Sri Lankan endemic C. maculatus as sister to all other sampled Cylindrophis. The mainland Southeast Asian species C. burmanus and C. jodiae form successive sister lineages to a monophyletic Wallacean island group containing C. boulengeri, C. isolepis, and C. yamdena. We also describe a new species of Cylindrophis, morphologically similar to C. burmanus, from Kachin State in northern Myanmar. Cylindrophis slowinskii sp. nov. is distinguished from all congeners by the following combination of characters: 19 dorsal scale rows at midbody, 216-220 ventrals, eight subcaudals, a dark venter with > 60 very narrow diffuse pale blotches, and a pale bar running along the posterior border of the prefrontals. In our phylogeny, the new species is strongly supported as the sister species of C. burmanus. It is the 15th currently recognised species in the genus, and the fourth from mainland Southeast Asia.