Search

To explore group maturation in an educational setting, the policy board of a teacher center consortium was studied over a year, using ethnographic research methods. The group proceeded through various development stages, but not according to the predicted pattern, and failed to reach maturity. Maturation was disrupted by the director's dominating behavior, state education department influences, and group size. (MLH)

The article provides information on Traveler-based Genomic Surveillance (TGS) program of the U.S. Center for Disease Control and Prevention (CDC) which was developed to provide early warning of new variants entering the U.S. by collecting samples from arriving international travelers. Topics include an overview of the program, investigation and outcomes, and preliminary conclusions and actions.

Emerging infectious diseases are a pressing threat to global biological diversity. Increased incidence and severity of novel pathogens underscores the need for methodological advances to understand pathogen emergence and spread. Here, we use genetic epidemiology to test, and challenge, key hypotheses about a devastating zoonotic disease impacting amphibians globally. Using an amplicon-based sequencing method and non-invasive samples we retrospectively explore the history of the fungal pathogen Batrachochytrium dendrobatidis (Bd) in two emblematic amphibian systems: the Sierra Nevada of California and Central Panama. The hypothesis in both regions is the hypervirulent Global Panzootic Lineage of Bd (BdGPL) was recently introduced and spread rapidly in a wave-like pattern. Our data challenge this hypothesis by demonstrating similar epizootic signatures can have radically different underlying evolutionary histories. In Central Panama, our genetic data confirm a recent and rapid pathogen spread. However, BdGPL in the Sierra Nevada has remarkable spatial structuring, high genetic diversity and a relatively older history inferred from time-dated phylogenies. Thus, this deadly pathogen lineage may have a longer history in some regions than assumed, providing insights into its origin and spread. Overall, our results highlight the importance of integrating observed wildlife die-offs with genetic data to more accurately reconstruct pathogen outbreaks. [ABSTRACT FROM AUTHOR]

Moving animals on a landscape through translocations and reintroductions is an important management tool used in the recovery of endangered species, particularly for the maintenance of population genetic diversity and structure. Management of imperiled amphibian species rely heavily on translocations and reintroductions, especially for species that have been brought to the brink of extinction by habitat loss, introduced species, and disease. One striking example of amphibian declines and associated management efforts is in California's Sequoia and Kings Canyon National Parks with the mountain yellow‐legged frog species complex (Rana sierrae/muscosa). Mountain yellow‐legged frogs have been extirpated from more than 93% of their historic range, and limited knowledge of their population genetics has made long‐term conservation planning difficult. To address this, we used 598 archived skin swabs from both extant and extirpated populations across 48 lake basins to generate a robust Illumina‐based nuclear amplicon data set. We found that samples grouped into three main genetic clusters, concordant with watershed boundaries. We also found evidence for historical gene flow across watershed boundaries with a north‐to‐south axis of migration. Finally, our results indicate that genetic diversity is not significantly different between populations with different disease histories. Our study offers specific management recommendations for imperiled mountain yellow‐legged frogs and, more broadly, provides a population genetic framework for leveraging minimally invasive samples for the conservation of threatened species. [ABSTRACT FROM AUTHOR]

Invasive plants are major drivers of habitat modification and the scale of their impact is increasing globally as anthropogenic activities facilitate their spread. In California, an invasive plant genus of great concern is Eucalyptus. Eucalyptus leaves can alter soil chemistry and negatively affect underground macro- and microbial communities. Amphibians serve as excellent models to evaluate the effect of Eucalyptus invasion on ground-dwelling species as they predate on soil arthropods and incorporate soil microbes into their microbiotas. The skin microbiota is particularly important to amphibian health, suggesting that invasive plant species could ultimately affect amphibian populations. To investigate the potential for invasive vegetation to induce changes in microbial communities, we sampled microbial communities in the soil and on the skin of local amphibians. Specifically, we compared Batrachoseps attenuatus skin microbiomes in both Eucalyptus globulus (Myrtaceae) and native Quercus agriflolia (Fagaceae) dominated forests in the San Francisco Bay Area. We determined whether changes in microbial diversity and composition in both soil and Batrachoseps attenuatus skin were associated with dominant vegetation type. To evaluate animal health across vegetation types, we compared Batrachoseps attenuatus body condition and the presence/absence of the amphibian skin pathogen Batrachochytrium dendrobatidis. We found that Eucalyptus invasion had no measurable effect on soil microbial community diversity and a relatively small effect (compared to the effect of site identity) on community structure in the microhabitats sampled. In contrast, our results show that Batrachoseps attenuatus skin microbiota diversity was greater in Quercus dominated habitats. One amplicon sequence variant identified in the family Chlamydiaceae was observed in higher relative abundance among salamanders sampled in Eucalyptus dominated habitats. We also observed that Batrachoseps attenuatus body condition was higher in Quercus dominated habitats. Incidence of Batrachochytrium dendrobatidis across all individuals was very low (only one Batrachochytrium dendrobatidis positive individual). The effect on body condition demonstrates that although Eucalyptus may not always decrease amphibian abundance or diversity, it can potentially have cryptic negative effects. Our findings prompt further work to determine the mechanisms that lead to changes in the health and microbiome of native species post-plant invasion. [ABSTRACT FROM AUTHOR]

The article reports that Wastewater surveillance in airports and on aircraft can enable detection of emerging SARS-CoV-2 variants. Topics include Aircraft wastewater samples from selected international flights were collected and tested for SARS-CoV-2 by Reverse transcriptase polymerase chain reaction and whole genome sequencing; and monitor SARS-CoV-2 variants without direct traveler involvement or disruption to airport operations and can complement traveler-based surveillance.

One of the most devastating emerging pathogens of wildlife is the chytrid fungus, Batrachochytrium dendrobatidis (Bd), which affects hundreds of amphibian species around the world. Genomic data from pure Bd cultures have advanced our understanding of Bd phylogenetics, genomic architecture and mechanisms of virulence. However, pure cultures are laborious to obtain and whole-genome sequencing is comparatively expensive, so relatively few isolates have been genetically characterized. Thus, we still know little about the genetic diversity of Bd in natural systems. The most common noninvasive method of sampling Bd from natural populations is to swab amphibian skin. Hundreds of thousands of swabs have been collected from amphibians around the world, but Bd DNA collected via swabs is often low in quality and/or quantity. In this study, we developed a custom Bd genotyping assay using the Fluidigm Access Array platform to amplify 192 carefully selected regions of the Bd genome. We obtained robust sequence data for pure Bd cultures and field-collected skin swabs. This new assay has the power to accurately discriminate among the major Bd clades, recovering the basic tree topology previously revealed using whole-genome data. Additionally, we established a critical value for initial Bd load for swab samples (150 Bd genomic equivalents) above which our assay performs well. By leveraging advances in microfluidic multiplex PCR technology and the globally distributed resource of amphibian swab samples, noninvasive skin swabs can now be used to address critical spatial and temporal questions about Bd and its effects on declining amphibian populations. [ABSTRACT FROM AUTHOR]

Individual-based data sets tracking organisms over space and time are fundamental to answering broad questions in ecology and evolution. A 'permanent' genetic tag circumvents a need to invasively mark or tag animals, especially if there are little phenotypic differences among individuals. However, genetic tracking of individuals does not come without its limits; correctly matching genotypes and error rates associated with laboratory work can make it difficult to parse out matched individuals. In addition, defining a sampling design that effectively matches individuals in the wild can be a challenge for researchers. Here, we combine the two objectives of defining sampling design and reducing genotyping error through an efficient Python-based computer-modelling program, wisepair. We describe the methods used to develop the computer program and assess its effectiveness through three empirical data sets, with and without reference genotypes. Our results show that wisepair outperformed similar genotype matching programs using previously published from reference genotype data of diurnal poison frogs ( Allobates femoralis) and without-reference (faecal) genotype sample data sets of harbour seals ( Phoca vitulina) and Eurasian otters ( Lutra lutra). In addition, due to limited sampling effort in the harbour seal data, we present optimal sampling designs for future projects. wisepair allows for minimal sacrifice in the available methods as it incorporates sample rerun error data, allelic pairwise comparisons and probabilistic simulations to determine matching thresholds. Our program is the lone tool available to researchers to define parameters a priori for genetic tracking studies. [ABSTRACT FROM AUTHOR]

Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. Andrew P. Rothstein, Casandra W. Philipson, Birgitte B. Simen, and Robert C. Morfino own Ginkgo Bioworks employee stocks or restricted stock unit grants. Ezra T. Ernst owns XWELL employee stocks or restricted stock unit grants. No other potential conflicts of interest were disclosed.

Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. Robert C. Morfino, Benjamin H. Rome, Andrew P. Rothstein, Siyao Lisa Li, and Thomas W. S. Aichele report Ginkgo Bioworks employee stocks or restricted stock units (RSU) grants. Aaron Bivins reports grants from the U.S. Environmental Protection Agency, Louisiana Water Resources Research Institute, and Louisiana State University, payments from BioRad Laboratories, and equipment or materials from Ceres Nanosciences. Ezra T. Ernst reports XWELL employee stocks or RSU grants. No other potential conflicts of interest were disclosed.

Scheele et al (Reports, 29 March 2019, p. 1459) bring needed attention to the effects of amphibian infectious disease. However, the data and methods implicating the disease chytridiomycosis in 501 amphibian species declines are deficient. Which species are affected, and how many, remains a critical unanswered question. Amphibians are imperiled; protective actions require public support and robust science., (Copyright © 2020, American Association for the Advancement of Science.)