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Despite large-scale population decline and geographic range contraction, Timber Rattlesnakes (Crotalus horridus) continue to occupy sites across much of eastern North America, including a diversity of habitat types. Here, our objective was to examine the influence of intrinsic and extrinsic factors on the movement and activity range of Timber Rattlesnakes in the Coastal Plain of southeastern Virginia. To do so, we analyzed the movements of 54 radio-implanted snakes over a period of 17 yr, with individuals being tracked for 1–6 yr, amounting to more than 14,000 snake locations. Consistent with previous studies, our results showed strong sexual differences in movements, with average daily and annual movements of males exceeding those of females. Mean annual movements of males were approximately 1.8 times greater than those of females, with a peak in male movements in late summer, associated with mate searching. Similarly, all estimates of activity ranges (using minimum convex polygon and kernel methods) were larger for males, with overall activity ranges approximately three times greater than for females. Gravid females had somewhat smaller movements and activity ranges than nongravid females, with early-season movements of gravid individuals to the birthing site, followed by shorter movements within that site, interpreted as serving a thermoregulatory function. The number of locations and body mass (of males) also appeared as significant factors in some models, although sex was the dominant factor in all models.

The chytrid fungus Batrachochytrium dendrobatidis ( Bd ) has been implicated in amphibian declines on almost all continents. We report on prevalence and intensity of Bd in the United States amphibian populations across three longitudinally separated north-to-south transects conducted at 15 Department of Defense installations during two sampling periods (late-spring/early summer and mid to late summer). Such a standardized approach minimizes the effects of sampling and analytical bias, as well as human disturbance (by sampling restricted military bases), and therefore permits a cleaner interpretation of environmental variables known to affect chytrid dynamics such as season, temperature, rainfall, latitude, and longitude. Our prevalence of positive samples was 20.4% (137/670), and our mean intensity was 3.21 zoospore equivalents (SE = 1.03; range 0.001–103.59). Of the 28 amphibian species sampled, 15 tested positive. Three sites had no evidence of Bd infection; across the remaining 12 Bd -positive sites, neither infection prevalence nor intensity varied systematically. We found a more complicated pattern of Bd prevalence than anticipated. Early season samples showed no trend associated with increasing temperature and precipitation and decreasing (more southerly) latitudes; while in late season samples, the proportion of infected individuals decreased with increasing temperature and precipitation and decreasing latitudes. A similar pattern held for the east–west gradient, with the highest prevalence associated with more easterly/recently warmer sites in the early season then shifting to more westerly/recently cooler sites in the later season. Bd intensity across bases and sampling periods was comparatively low. Some of the trends in our data have been seen in previous studies, and our results offer further continental-level Bd sampling over which more concentrated local sampling efforts can be overlaid.

During a 17-yr telemetry study, we examined the diet and ambush behavior of a population of Crotalus horridus in southeastern Virginia. Forty dietary items were identified from 37 fecal samples. We documented 722 instances of snakes in an ambush posture, 61% of which were in a vertical-tree posture, as if hunting arboreal prey at the base of a tree. The most common prey items were Eastern Gray Squirrels (Sciurus carolinensis), which accounted for 45% of all dietary items and represented an estimated 78% of total biomass consumed by C. horridus. Prey was not consumed in proportion to availability, based on small mammal surveys. Our analysis provides indirect evidence that the vertical-tree foraging behavior is adopted to target arboreal Eastern Gray Squirrels. Further, we provide support for the hypothesis that C. horridus alters ambush behavior to forage selectively for specific prey types.

Multivariate analysis of snake microhabitat has historically used techniques that were derived under assumptions of normality and common covariance structure (e.g., discriminant function analysis, MANOVA). In this study, polytomous logistic regression (PLR), which does not require such assumptions, was developed to model habitat use patterns from snake radiotelemetry data. Two case study examples were used: the copperhead (Agkistrodon contortrix) in a forested habitat in Chesapeake, Virginia, and the cottonmouth (Agkistrodon piscivorus piscivorus) in a wetland habitat in Virginia Beach, Virginia. The model was developed based on grid-cell counts of the habitat used by adult snakes that were radiotracked for a minimum of one activity season (early spring through late fall). In addition to PLR modeling, a nonparametric MANOVA procedure based on ranked data from presence versus random sites was developed for comparative purposes. Although results were similar in terms of variables chosen by the models, nonparametric procedures lack predictive power, and conclusions drawn from them are sometimes questionable or difficult to interpret. Polytomous logistic regression provides a useful alternative to traditional modeling approaches that require ancillary data from random sites; PLR requires data only from sites used by snakes, and was developed based on use-intensity categorization. Suggestions for model implementation (e.g., in a GIS) are discussed.

The timber rattlesnake (Crotalus horridus) occurs in discontinuous populations across the eastern and central United States. The species exhibits high levels of polymorphism in morphological traits, especially in coloration and pattern. Previous studies recognized either distinct northern and southern subspecies or three regional morphs (northern, southern, and western), but the conflicting data sets and limited geographic sampling of previous studies have left the relationships among those regional variants unclear. In this study, univariate and multivariate statistics, analyzed in conjunction with a geographic information system, were used to examine geographic variation in 36 morphological characters recorded from 2420 specimens of C. horridus across its range. Univariate analyses detected substantial geographic variation in all meristic characters. Scutellation exhibited a general north–south pattern of variation, and most scale counts averaged higher in southern regions. Pattern characters differentiated the northeastern, central-eastern, and north-central regions from the southern and western regions. Coloration displayed a pattern of strong clinal variation among three broad areas consisting of the combined northeastern, central-eastern, and southern Appalachian regions, the northwestern regions, and the southern regions. Morphometric characters exhibited a general north–south pattern of geographic variation, with larger head and body sizes in southern regions. Sexual dimorphism was strong in ventral and subcaudal scales, and weak to moderate in band length and band spacing. Principal component analysis indicated that band length was the most important variable for characterizing geographic variation. The northeastern regions remained moderately distinct in all multivariate cluster analyses. The northwestern regions appeared very distinct in most cluster analyses for females. However, the clusters in all models showed extensive geographic overlap. Maps of the clusters revealed two north–south patterns of clinal variation across the northeastern, northwestern, and southern regions. The discordant patterns of variation among individual characters, overlapping patterns of coloration, and extensive overlap among the multivariate clusters collectively indicate that the putative zones of intergradation among recognized subpopulations of C. horridus are much broader than previously thought. Furthermore, because the general patterns of geographic variation are strongly clinal, our results support the conclusion that C. horridus is a single widespread species with variation too extensive and complex to be reflected by formal subspecific designations.

The timber rattlesnake (Crotalus horridus) occurs in discontinuous populations across the eastern and central United States. The species exhibits high levels of polymorphism in morphological traits, especially in coloration and pattern. Previous studies recognized either distinct northern and southern subspecies or three regional morphs (northern, southern, and western), but the conflicting data sets and limited geographic sampling of previous studies have left the relationships among those regional variants unclear. In this study, univariate and multivariate statistics, analyzed in conjunction with a geographic information system, were used to examine geographic variation in 36 morphological characters recorded from 2420 specimens of C. horridus across its range. Univariate analyses detected substantial geographic variation in all meristic characters. Scutellation exhibited a general north–south pattern of variation, and most scale counts averaged higher in southern regions. Pattern characters differentiated the northeastern, central-eastern, and north-central regions from the southern and western regions. Coloration displayed a pattern of strong clinal variation among three broad areas consisting of the combined northeastern, central-eastern, and southern Appalachian regions, the northwestern regions, and the southern regions. Morphometric characters exhibited a general north–south pattern of geographic variation, with larger head and body sizes in southern regions. Sexual dimorphism was strong in ventral and subcaudal scales, and weak to moderate in band length and band spacing. Principal component analysis indicated that band length was the most important variable for characterizing geographic variation. The northeastern regions remained moderately distinct in all multivariate cluster analyses. The northwestern regions appeared very distinct in most cluster analyses for females. However, the clusters in all models showed extensive geographic overlap. Maps of the clusters revealed two north–south patterns of clinal variation across the northeastern, northwestern, and southern regions. The discordant patterns of variation among individual characters, overlapping patterns of coloration, and extensive overlap among the multivariate clusters collectively indicate that the putative zones of intergradation among recognized subpopulations of C. horridus are much broader than previously thought. Furthermore, because the general patterns of geographic variation are strongly clinal, our results support the conclusion that C. horridus is a single widespread species with variation too extensive and complex to be reflected by formal subspecific designations.

The timber rattlesnake (Crotalus horridus) occurs in discontinuous populations across the eastern and central United States. The species exhibits high levels of polymorphism in morphological traits, especially in coloration and pattern. Previous studies recognized either distinct northern and southern subspecies or three regional morphs (northern, southern, and western), but the conflicting data sets and limited geographic sampling of previous studies have left the relationships among those regional variants unclear. In this study, univariate and multivariate statistics, analyzed in conjunction with a geographic information system, were used to examine geographic variation in 36 morphological characters recorded from 2420 specimens of C. horridus across its range. Univariate analyses detected substantial geographic variation in all meristic characters. Scutellation exhibited a general north-south pattern of variation, and most scale counts averaged higher in southern regions. Pattern characters differentiated the northeastern, central-eastern, and north-central regions from the southern and western regions. Coloration displayed a pattern of strong clinal variation among three broad areas consisting of the combined northeastern, central-eastern, and southern Appalachian regions, the northwestern regions, and the southern regions. Morphometric characters exhibited a general north-south pattern of geographic variation, with larger head and body sizes in southern regions. Sexual dimorphism was strong in ventral and subcaudal scales, and weak to moderate in band length and band spacing. Principal component analysis indicated that band length was the most important variable for characterizing geographic variation. The northeastern regions remained moderately distinct in all multivariate cluster analyses. The northwestern regions appeared very distinct in most cluster analyses for females. However, the clusters in all models showed extensive geographic overlap. Maps of the clusters revealed two north-south patterns of clinal variation across the northeastern, northwestern, and southern regions. The discordant patterns of variation among individual characters, overlapping patterns of coloration, and extensive overlap among the multivariate clusters collectively indicate that the putative zones of intergradation among recognized subpopulations of C. horridus are much broader than previously thought. Furthermore, because the general patterns of geographic variation are strongly clinal, our results support the conclusion that C. horridus is a single widespread species with variation too extensive and complex to be reflected by formal subspecific designations.

This memorial volume both displays and evaluates the canonical approach of Brevard S. Childs, whose attention to history through time animated his interest in the Bible’s use in the church through the ages up to and including the present. Just as Childs wrote on a wide range of topics canonical and theological—both Testaments, Isaiah and Exodus, the Pauline letters, the history of biblical interpretation, biblical theology, and historical, theological, and methodological questions—the contributors to this volume, seasoned colleagues as well as younger scholars who studied with Childs, offer an international collection of historical, theological, and New Testament essays as well as contributions focused on the Old Testament. The contributors are Stephen B. Chapman, Brevard S. Childs, Don Collett, Daniel R. Driver, Mark W. Elliott, Leonard G. Finn, Mark Gignilliat, Bernd Janowski, Jörg Jeremias, Leander E. Keck, Neil B. MacDonald, David L. Petersen, Murray A. Rae, C. Kavin Rowe, and Christopher R. Seitz.

This study from the CDC compared the characteristics of 60 patients who died from EVALI with those of 2558 patients who were hospitalized for the condition but survived. The deaths were reported from 27 states and the District of Columbia, and most were associated with vaping THC-containing products before symptom onset.

Hypertrophic cardiomyopathy (HCM) is a common, serious, genetic heart disorder. Rare pathogenic variants in sarcomere genes cause HCM, but with unexplained phenotypic heterogeneity. Moreover, most patients do not carry such variants. We report a genome-wide association study of 2,780 cases and 47,486 controls that identified 12 genome-wide-significant susceptibility loci for HCM. Single-nucleotide polymorphism heritability indicated a strong polygenic influence, especially for sarcomere-negative HCM (64% of cases; h 2 g  = 0.34 ± 0.02). A genetic risk score showed substantial influence on the odds of HCM in a validation study, halving the odds in the lowest quintile and doubling them in the highest quintile, and also influenced phenotypic severity in sarcomere variant carriers. Mendelian randomization identified diastolic blood pressure (DBP) as a key modifiable risk factor for sarcomere-negative HCM, with a one standard deviation increase in DBP increasing the HCM risk fourfold. Common variants and modifiable risk factors have important roles in HCM that we suggest will be clinically actionable. Genome-wide association analyses identify 12 susceptibility loci for hypertrophic cardiomyopathy (HCM). A genetic risk score for HCM was associated with disease status in a validation study and influenced phenotypic severity in carriers of risk variants in sarcomere genes.