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We developed a curriculum for an upper-level molecular biology course-based undergraduate research laboratory class funded by a National Science Foundation CAREER grant that focuses on identifying new small proteins in the bacterium, "Escherichia coli." Our CURE class has been continually offered each semester for the last 10 years, with multiple instructors collaboratively developing and implementing their own pedagogical approach while maintaining the same overall scientific goal and experimental strategy. In this paper, we delineate the experimental strategy for our molecular biology CURE laboratory class, describe a range of pedagogical approaches implemented by multiple instructors, and provide recommendations for teaching the class. The purpose of our paper is to share our experiences both in developing and teaching a molecular biology CURE laboratory class based on small protein identification and in creating a curriculum and support system that allows traditional, non-traditional, and under-represented students to participate in authentic research projects.

Effective population size (NE) is an important parameter for conservation of threatened wildlife. Current estimators of NE that use genetic data, however, may not be equally useful among taxa that are difficult to sample, such as cryptic, iteroparous, long‐lived herpetofauna. To better understand the use of NE estimators for such taxa, we generated and compared contemporary NE estimates to evaluate methods, repeatability, and the effects of sample size at management scales and functional genetic population scales for the eastern box turtle (Terrapene carolina carolina) and eastern hellbender (Cryptobranchus alleganiensis alleganiensis). We chose these 2 species for their differing dispersal abilities, reproductive variances, and natural history traits, which may be useful in exploring the weaknesses and strengths of NE estimators. We collected species‐specific microsatellite genotypes from 2,712 individuals (1,133 hellbenders, 1,579 box turtles) in 2007–2011 from across their ranges in the eastern United States. We then grouped samples into range‐wide genetic clusters, state‐level management populations, and small regional management populations (e.g., state parks). We also randomly subsampled (rarefied) from these 3 categories to explore the effects of reduced sampling effort on NE estimates. We used 4 popular estimators: NEESTIMATOR (linkage disequilibrium and heterozygote excess methods), LDNE, and ONESAMP. Over half of all attempts at estimating NE failed to give complete estimates (those that included only non‐negative and non‐infinity values). There was variation between species but also among estimators. Repeated sampling of genetic populations resulted in inconsistent results, and estimates generally increased with sample size. The linkage disequilibrium version of NEESTIMATOR returned the largest percentage (95.8%) of complete estimates. Program ONESAMP obtained complete estimates for 62.0% of attempts and generally provided the numerically largest estimates. Only 19.4% of LDNE estimates and none of the heterozygote excess version of NEESTIMATOR estimates were complete. Generally, NE estimates were higher for box turtles, perhaps because of their greater dispersal capabilities, historically larger populations, and longer lifespans. Our results suggest that estimates of NE for long‐lived herpetofauna species vary according to species, sample size, genetic cluster, management population, and estimator used. Therefore, we recommend managers of populations of long‐lived herpetofaunal species use NE estimators with caution, and consider results from multiple methods before incorporating NE into management practice. [ABSTRACT FROM AUTHOR]

The article discusses the observation of an albino American toad (Anaxyrus americanus) at Glen Arboretum, Towson University, Maryland, a rare occurrence given the species' typical brown, olive, gray, yellow, or orange coloration and the higher visibility of albino amphibians to predators.

A Ranavirus outbreak in a captive population of wild-caught individuals was monitored using clinical evaluations and real-time PCR in 317 wild box turtles held in captivity during translocation. During the 2-year study period, the population experienced 71.6% mortality, suggesting that ranaviruses can rapidly attenuate populations. Wide variation in infection rate (7-94% per sampling period) was observed, which may have been driven by clearing and reinfection, adaptive immunity, or imperfect detection using noninvasive samples. Only nasal clinical signs were significantly related to infection status, and agreement among sample types was low. Subsequent to the initial outbreak, low mortality but high real-time PCR prevalence of Ranavirus was observed, suggesting that surviving individuals might be tolerant. [ABSTRACT FROM AUTHOR]

Genetic diversity (GD) is largely determined by effective population size, which may vary dramatically for species that differ in key aspects of their biology such as vagility. To identify evolutionary patterns associated with animal distributions and movements, we examined relationships among GD (i.e. microsatellite heterozygosity and allelic richness), taxonomic class, biome and migratory behaviour. Linear regression revealed that migratory mammals, reptiles, amphibians and fishes had less GD compared to nonmigratory species, whereas migratory birds had more GD than their nonmigratory counterparts. We also found that the biome a species inhabits influences the GD of migratory and nonmigratory species differently. For example, migratory amphibians at low latitudes are more genetically diverse than migratory amphibians at higher latitudes. However, we found the reverse relationship (i.e. decreased GD in low-latitude migratory species compared to higher latitude migratory species) in mammals and fishes and no influence of biome on reptile GD. We suggest that these differences are a result of differences in vagility, the extent of philopatry among the classes and perhaps differential selection between terrestrial and aquatic species. We argue that these categorical disparities in GD reflect changes in effective population size driven at least partly by differences in habitat. [ABSTRACT FROM AUTHOR]

Ranaviruses are significant pathogens of amphibians, reptiles, and fishes, contributing to mass mortality events worldwide. Despite an increasing focus on ranavirus ecology, our understanding of ranavirus transmission, especially among reptilian hosts, remains limited. For example, experimental evidence for oral transmission of the virus in chelonians is mixed. Consequently, vector-borne transmission has been hypothesized in terrestrial turtle species. To test this hypothesis, mosquitoes captured during a 2012/2013 ranavirus outbreak in box turtles from southwestern Indiana were pooled by genus and tested for ranavirus DNA using qPCR. Two of 30 pools tested positive for ranavirus. Additionally, an individual Aedes sp. mosquito observed engorging on a box turtle also tested positive for ranavirus. Although our approach does not rule out the possibility that the sequenced ranavirus was simply from virus in bloodmeal, it does suggests that mosquitoes may be involved in virus transmission as a mechanical or biological vector among ectothermic vertebrates. While additional studies are needed to elucidate the exact role of mosquitoes in ranavirus ecology, our study suggests that a greater focus on vector-borne transmission may be necessary to fully understand ranaviral disease dynamics in herpetofauna. [ABSTRACT FROM AUTHOR]

The article focuses on fatal interspecific amplexus involving the species Lithobates sylvaticus and Lithobates maculatum.

The article discusses a study which examined the seasonal variation in hematology and blood plasma chemistry values of the timber rattlesnake (Crotalus horridus). The study processed blood from 13 rattlesnakes found in Indiana and determined their packed cell volume. It presented hematologic, biochemical and body condition index for the animals.

Rangewide studies of genetic parameters can elucidate patterns and processes that operate only over large geographic scales. Herein, we present a rangewide population genetic assessment of the eastern box turtle Terrapene c. carolina, a species that is in steep decline across its range. To inform conservation planning for this species, we address the hypothesis that disruptions to demographic and movement parameters associated with the decline of the eastern box turtle has resulted in distinctive genetic signatures in the form of low genetic diversity, high population structuring, and decreased gene flow. We used microsatellite genotype data from (n = 799) individuals from across the species range to perform two Bayesian population assignment approaches, two methods for comparing historical and contemporary migration among populations, an evaluation of isolation by distance, and a method for detecting barriers to gene flow. Both Bayesian methods of population assignment indicated that there are two populations rangewide, both of which have maintained high levels of genetic diversity (HO = 0.756). Evidence of isolation by distance was detected in this species at a spatial scale of 300 – 500 km, and the Appalachian Mountains were identified as the primary barrier to gene flow across the species range. We also found evidence for historical but not contemporary migration between populations. Our prediction of many, highly structured populations across the range was not supported. This may point to cryptic contemporary gene flow, which might in turn be explained by the presence of rare transients in populations. However these data may be influenced by historical signatures of genetic connectivity because individuals of this species can be long-lived. [ABSTRACT FROM AUTHOR]

Rangewide studies of genetic parameters can elucidate patterns and processes that operate only over large geographic scales. Herein, we present a rangewide population genetic assessment of the eastern box turtle Terrapene c. carolina, a species that is in steep decline across its range. To inform conservation planning for this species, we address the hypothesis that disruptions to demographic and movement parameters associated with the decline of the eastern box turtle has resulted in distinctive genetic signatures in the form of low genetic diversity, high population structuring, and decreased gene flow. We used microsatellite genotype data from (n = 799) individuals from across the species range to perform two Bayesian population assignment approaches, two methods for comparing historical and contemporary migration among populations, an evaluation of isolation by distance, and a method for detecting barriers to gene flow. Both Bayesian methods of population assignment indicated that there are two populations rangewide, both of which have maintained high levels of genetic diversity (HO = 0.756). Evidence of isolation by distance was detected in this species at a spatial scale of 300 – 500 km, and the Appalachian Mountains were identified as the primary barrier to gene flow across the species range. We also found evidence for historical but not contemporary migration between populations. Our prediction of many, highly structured populations across the range was not supported. This may point to cryptic contemporary gene flow, which might in turn be explained by the presence of rare transients in populations. However these data may be influenced by historical signatures of genetic connectivity because individuals of this species can be long-lived. [ABSTRACT FROM AUTHOR]

Molecular ecologists have good reasons to be excited about the newest DNA/RNA sequencing technologies. However, this exuberance should be tempered with a hefty dose of reality: new sequencing technologies come with significant new challenges. Herein, we offer a brief overview of some practical problems encountered during transcriptomics studies conducted in our laboratory, and of nontrivial issues that prospective practitioners should consider. These include template contamination (e.g. from xenobiotics) and the cutting-room floor problem, whereby most of the data are often unassembled, unannotated and unused. We also highlight computational requirements, including hardware, personnel time and associated skill sets. We are very optimistic about the future of molecular ecology, but we hope this cautionary overview will help neophytes better recognize some key challenges associated with new technologies. [ABSTRACT FROM AUTHOR]

The article discusses research on the temporal hematologic and biochemical reference intervals for free-ranging Eastern box turtles. It cites reasons behind the decline of these turtles which include habitat loss, road mortality and disease. Experimental procedures which include blood sample collection and analysis are detailed. The hematologic and plasma biochemistry values recorded which include bile acids, globulin and creatine kinase are also outlined.

The article discusses the results of a study of the prevalence of ranavirus infections (RI) in larval Green Frogs and American Bullfrogs in Indiana, which was conducted by the state Department of Natural Resources in 2014 and 2014. Topics covered include the correlation between RI prevalence and site types, and the use of a phenol-chloroform-isoamyl alcohol extraction method to extract deoxyribonucleic acid (DNA) from the kidney and liver tissue samples.