Amphibian Species Contribute Similarly to Taxonomic, but not Functional and Phylogenetic Diversity: Inferences from Amphibian Biodiversity on Emei Mountain

Understanding the relationships between species, communities, and biodiversity are important challenges in conservation ecology. Current biodiversity conservation activities usually focus on species that are rare, endemic, distinctive, or at risk of extinction. However, empirical studies of whether such species contribute more to aspects of biodiversity than common species are still relatively rare. The aim of the present study was to assess the contribution of individual amphibian species to different facets of biodiversity, and to test whether species of conservation interest contribute more to taxonomic, functional, and phylogenetic diversity than do species without special conservation status. To answer these questions, 19 000 simulated random communities with a gradient of species richness were created by shuffling the regional pool of species inhabiting Emei Mountain. Differences of diversity values were then computed before and after removing individual species in these random communities. Our results indicated that although individual species contributed similarly to taxonomic diversity, their contribution to functional and phylogenetic diversity was more idiosyncratic. This was primarily driven by the diverse functional attributes of species and the differences in phylogenetic relationships among species. Additionally, species of conservation interest did not show a significantly higher contribution to any facet of biodiversity. Our results support the claims that the usefulness of metrics based only on species richness is limited. Instead, assemblages that include species with functional and phylogenetic diversity should be protected to maintain biodiversity

A Rapid, Non-invasive Method for Anatomical Observations of Tadpole Vertebrae in Vivo

The tadpole is a critical stage in the amphibian life cycle and plays an important role during the transition from the aquatic to the terrestrial stage. However, there is a large gap in tadpole research, which represents a vital component of our understanding of the diversity and complexity of the life history traits of amphibians, especially their developmental biology. Some aspects of this gap are due to limited research approaches. To date, X-ray microcomputed tomography (micro-CT) has been widely used to conduct osteology research in adult amphibians and reptiles, but little is known about whether this tool can be applied in tadpole studies. Thus, we compared the results of two methods (the bone-cartilage double-staining technique and micro-CT) to study vertebrae in tadpole specimens. The results revealed no significant difference between the two methods in determining the number of vertebrae, and micro-CT represents a rapid, non-invasive, reliable method of studying tadpole vertebrae. When scanning tadpoles, voltage is the most critical of the scanning parameters (voltage, current and scan time), and moderate scanning parameters are recommended. In addition, micro-CT performed better using specimens stored in 70% ethanol than those preserved in 10% formalin. Finally, we suggest that micro-CT should be more widely applied in herpetological research to increase specimen utilization

Daytime driving decreases amphibian roadkill

Roadkill has gradually become a common factor that has contributed to the decline of amphibians, and traffic volume is an important parameter that can be used to determine the impacts of roads. However, few researchers have studied the effects of either daily or nightly traffic volume on amphibian roadkill in China. Hence, as an essential step for implementing mitigation measures, we conducted 77 road surveys along 10 km of road in the Wanglang National Nature Reserve (NNR) to determine the temporal and spatial distribution patterns of amphibian road mortality. In total, 298 dead individuals (Bufo andrewsi and Rana chensinensis) were observed on the road from April to October in 2017 and during June and August in 2015 and 2016. B. andrewsi had the highest number of records (85.2%) and was more vulnerable to road mortality than R. chensinensis. Amphibian fatalities mainly occurred during the breeding season in April, but there was an additional concentration of B. andrewsi roadkill in June and July. There was a significantly positive correlation between amphibian road mortality and mean night-time traffic volume. Roadkill hotspots were non-randomly distributed throughout the study area and were mainly concentrated in the road sections near the breeding pools. Therefore, to effectively mitigate the effects of road mortality in the Wanglang NNR, measures should be implemented both during hot moments and at hotspots. First, based on roadkill hot moments, during the breeding season (in April) and in June and July, the Wanglang NNR should establish temporary traffic restraints at night. Second, based on roadkill hotspots, culverts should be established in areas near breeding pools adjacent to roads, and barrier walls should be installed to guide amphibians into the culverts

Establishment of porcine and human expanded potential stem cells.

We recently derived mouse expanded potential stem cells (EPSCs) from individual blastomeres by inhibiting the critical molecular pathways that predispose their differentiation. EPSCs had enriched molecular signatures of blastomeres and possessed developmental potency for all embryonic and extra-embryonic cell lineages. Here, we report the derivation of porcine EPSCs, which express key pluripotency genes, are genetically stable, permit genome editing, differentiate to derivatives of the three germ layers in chimeras and produce primordial germ cell-like cells in vitro. Under similar conditions, human embryonic stem cells and induced pluripotent stem cells can be converted, or somatic cells directly reprogrammed, to EPSCs that display the molecular and functional attributes reminiscent of porcine EPSCs. Importantly, trophoblast stem-cell-like cells can be generated from both human and porcine EPSCs. Our pathway-inhibition paradigm thus opens an avenue for generating mammalian pluripotent stem cells, and EPSCs present a unique cellular platform for translational research in biotechnology and regenerative medicine

Complete mitochondrial genome of the Alpine Metacarpal-tubercled Toad Leptobrachella alpina (Amphibia, Anura, Megophryidae)

The complete mitochondrial genome of the Leptobrachella alpina Fei, Ye, and Li 1990, was assembled for the first time. The mitogenome of this species was 17,763 bp in length, containing 13 protein-coding genes, two ribosomal RNA genes (12S rRNA and 16S rRNA), 22 transfer RNA genes (tRNA), and a non-coding control region (D-loop). The base content of the mitogenome was that A, T, G, and C occupied 28.5%, 30.8%, 15.1%, and 25.6%, respectively. The phylogenetic analysis was conducted based on 17 complete mitogenome sequences of the family Megophryidae by the Bayesian inference approach. The phylogenetic tree suggested that Leptobrachium and Oreolalax clustered into a clade and formed a sister group with Leptobrachella. This work is critical for the further genetic research and conservation of this species

The mitochondrial genome of the Microhyla taraiensis (Anura: Microhylidae) and related phylogenetic analyses

The complete mitochondrial genome of the Microhyla taraiensis from Eastern Nepal was sequenced. The genome has a typical gene order identical to most of other anuran species. The entire mtDNA of this species, 16,764 bp in length, containing 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes, and a control region. Phylogenetic relationships was constructed based on the complete mitogenome of M. taraiensis and other species of Microhylidae, using Bayesian inferences and Maximum likelihood approaches, and supports the monophly for this family. This work contributes to basic molecular data which is critical for further genetic research and conservation of this newly described species

Effects of long-term preservation on amphibian body conditions: Implications for historical morphological research

Measurements of historical specimens are widely applied in studies of taxonomy, systematics, and ecology, but biologists often assume that the effects of preservative chemicals on the morphology of amphibian specimens are minimal in their analyses. We compared the body length and body mass of 182 samples of 13 live and preserved (up to 10 years) anuran species and found that the body length and body mass of preserved specimens significantly decreased by 6.1% and 24.8%, respectively, compared to those measurements of their live counterparts. The changes in body length and mass also exhibited highly significant variations between species. Similarly, there were significant differences in shrinkage of body length and body mass between sexes, where males showed greater shrinkage in body length and body mass compared to females. Preservation distorted the magnitude of the interspecific differences in body length observed in the fresh specimens. Overall, the reduction in body length or mass wasgreater in longer or heavier individuals. Due to the effects of preservation on amphibian morphology, we propose two parsimonious conversion equations to back-calculate the original body length and body mass of studied anurans for researchers working with historical data, since morphological data from preserved specimens may lead to incorrect biological interpretations when comparing to fresh specimens. Therefore, researchers should correct for errors due to preservation effects that may lead to the misinterpretation of results

A new ovoviviparous rat snake species of the genus Elaphe (Squamata: Colubridae) from western Sichuan, China

The genus Elaphe is a highly diverse snake group with wide distribution in Eurasia. Here, based on morphological comparisons and molecular data, we describe a new species of this genus from western Sichuan, China. Bayesian inference and maximum-likelihood analyses of two mitochondrial DNA fragments (CO1 and 12S) showed that the new taxon differs from its congeners (CO1-based p-distance ≥ 4.1%). Morphologically and ecologically, the new species can be diagnosed from other species by a combination of the following characters: 1) medium body size, 2) midbody dorsal scales in 23 rows generally, not keeled; 3) ventrals 169–180 and subcaudal pairs 56–63; 4) first preocular docked with frontal; 5) internasal scales approximately trapezoidal; 6) length of gap between internasals more than 3/5 that between prefrontal; 7) length of tip of snout to frontal slightly larger than length of frontal; 8) ovoviviparous. Currently, the new species is known only from the Sichuan and Shaanxi provinces in China. This new species brings the total number of species in the genus Elaphe to 18

Effects of long-term preservation on amphibian body conditions: Implications for historical morphological research Effects of long-term preservation on amphibian body conditions: Implications for historical morphological research

Measurements of historical specimens are widely applied in studies of taxonomy, systematics, and ecology, but biologists often assume that the effects of preservative chemicals on the morphology of amphibian specimens do not affect their analyses. We compared the body length and body mass of 14 live and preserved (up to 10 years) amphibian species and found that the body length and body mass of preserved specimens significantly decreased by 7.1% and 26.7%, respectively, compared to those measurements of their live counterparts. Additionally, there was greater body length (3.6%) and body mass (6.6%) shrinkage in the order Urodela than in the order Anura, but there were no significant differences in body length and body mass shrinkage between males and females. Furthermore, preservation apparently distorted the magnitude of the intersexual and interspecific differences in body length observed in the fresh specimens. When species were compared, we found that the shrinkage was proportionately greater in longer species, while the body mass of heavier individuals shrank proportionately less than that of lighter individuals. Due to the effects of preservation on amphibian morphology, we propose parsimonious conversion equations to back-calculate the original body length and body mass of study animals for researchers working with historical data because morphological data from preserved specimens may lead to incorrect biological interpretations. Therefore, researchers must correct for errors due to preservation effects that may lead to the misinterpretation of results. Abstract Measurements of historical specimens are widely applied in studies of taxonomy, systematics, and ecology, but biologists often assume that the effects of preservative chemicals on the morphology of amphibian specimens do not affect their analyses. We compared the body length and body mass of 14 live and preserved (up to 10 years) amphibian species and found that the body length and body mass of preserved specimens significantly decreased by 7.1% and 26.7%, respectively, compared to those measurements of their live counterparts. Additionally, there was greater body length (3.6%) and body mass (6.6%) shrinkage in the order Urodela than in the order Anura, but there were no significant differences in body length and body mass shrinkage between males and females. Furthermore, preservation apparently distorted the magnitude of the intersexual and interspecific differences in body length observed in the fresh specimens. When species were compared, we found that the shrinkage was proportionately greater in longer species, while the body mass of heavier individuals shrank proportionately less than that of lighter individuals. Due to the effects of preservation on amphibian morphology, we propose parsimonious conversion equations to back-calculate the original body length and body mass of study animals for researchers working with historical data because morphological data from preserved specimens may lead to incorrect biological interpretations. Therefore, researchers must correct for errors due to preservation effects that may lead to the misinterpretation of results

Analysis of Height of the Stable Boundary Layer in Summer and Its Influencing Factors in the Taklamakan Desert Hinterland

Stable boundary layer height (SBLH) is an important parameter to characterize the characteristics and vertical structure of the nocturnal lower atmosphere at night. The distribution of SBLH has obvious spatial and temporal differences, and there are many meteorological factors affecting the SBLH, but at present, there are few quantitative studies on the effects of near-surface meteorological factors on the SBLH in the desert hinterland. This study was based on GPS sounding balloon data, near-surface meteorological observation data, and ERA5 data from Tazhong Station (TZ) in the Taklamakan Desert (TD) collected in July 2017, 2019, and 2021. The variation characteristics of the SBLH and its relationship with near-surface meteorological factors are described. We quantitatively analyzed the degree of influence of near-surface meteorological factors affecting the SBLH and verified it using a model. The study also elucidates the possible formation mechanism of the SBLH in the TD hinterland. The SBLH in the TD hinterland trended upward in July 2017, 2019, and 2021, which is consistent with the changes in meteorological factors, according to the near-surface meteorological observation and ERA5 data. Therefore, we think that an inherent connection exists between near-surface meteorological factors and the SBLH. The results of correlation analysis show that complex internal connections and interactions exist among the meteorological factors near the ground; some thermal, dynamic, and other meteorological factors strongly correlate with the SBLH. Having established the change in SBLH (ΔSBLH) and in major thermal, dynamic, and other meteorological factors (Δ), the linear regression equation between them revealed that near-surface meteorological factors can affect the SBLH. The dynamic factors have a stronger influence on the ΔSBLH than thermal and other factors. The results of model validation based on the variable importance projection (VIP) also confirmed that the SBLH in the TD hinterland is jointly affected by dynamic and thermal factors, but the dynamic factors have a stronger impact. The mechanism through which the SBLH forms is relatively complex. At night, surface radiative cooling promotes the formation of a surface inversion layer, and low-level jets strengthen wind shear, reducing atmospheric stability. The combined effects of heat and dynamics play an important role in dynamically shaping the SBLH. This study helps us with accurately predicting and understanding the characteristics of the changes in and the factors influencing the SBLH in the TD hinterland, providing a reference for understanding the mechanism through which the SBLH forms in this area. At the same time, it provides a scientific basis for regional weather and climate simulation, meteorological disaster defense, air quality forecasting, and model parameterization improvement