Christopher L Parkinson

Christopher L Parkinson
Clemson University | CU · Department of Biological Sciences

About

325
Publications
36,064
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5,550
Citations
Citations since 2017
50 Research Items
1970 Citations
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20172018201920202021202220230100200300

Publications

Publications (325)
Article
Traits for prey acquisition form the phenotypic interface of predator–prey interactions. In venomous predators, morphological variation in venom delivery apparatus like fangs and stingers may be optimized for dispatching prey. Here, we determine how a single dimension of venom injection systems evolves in response to variation in the size, climatic...
Article
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Male mating strategies respond to female availability such that variation in resources that affect spatial distribution can also alter cost-benefit tradeoffs within a population. In arid-adapted species, rainfall alters reproduction, behavior, morphology, and population density such that populations differing in resource availability may also diffe...
Article
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Despite the medical significance to humans and important ecological roles filled by vipers, few high-quality genomic resources exist for these snakes outside of a few genera of pitvipers. Here we sequence, assemble, and annotate the genome of Fea’s Viper (Azemiops feae). This taxon is distributed in east Asia and belongs to a monotypic subfamily, s...
Article
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Beyond providing critical information to biologists, species distributions are useful for naturalists, curious citizens, and applied disciplines including conservation planning and medical intervention. Venomous snakes are one group that highlight the importance of having accurate information given their cosmopolitan distribution and medical signif...
Article
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Background Higher viral loads in SARS-CoV-2 infections may be linked to more rapid spread of emerging variants of concern (VOC). Rapid detection and isolation of cases with highest viral loads, even in pre- or asymptomatic individuals, is essential for the mitigation of community outbreaks. Methods and findings In this study, we analyze Ct values...
Article
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Understanding the joint roles of amino acid sequences variation of proteins and differential expression during adaptive evolution is a fundamental, yet largely unrealized, goal of evolutionary biology. Here, we use phylogenetic path analysis to analyze a comprehensive venom gland transcriptome dataset spanning three genera of pitvipers to identify...
Preprint
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Background Higher viral loads in SARS-CoV-2 infections may be linked to more rapid spread of emerging Variants of Concern. Rapid detection and isolation of cases with highest viral loads, even in pre- or asymptomatic individuals, is essential for the mitigation of community outbreaks. Methods and Findings In this study, we analyze Ct values from 1...
Article
[https://doi.org/10.1016/j.toxicon.2021.11.009] Most traditional research on snake venoms has focused on front-fanged snake families (Viperidae, Elapidae, and Atractaspididae). However, venom is now generally accepted as being a much more broadly possessed trait within snakes, including species traditionally considered harmless. Unfortunately, due...
Article
Intraspecific variation in snake venoms has been widely documented worldwide. However, there are few studies on this subject in Mexico. Venom characterization studies provide important data used to predict clinical syndromes, to evaluate the efficacy of antivenoms and, in some cases, to improve immunogenic mixtures in the production of antivenoms....
Article
Full-text available
The venoms of small rear-fanged snakes (RFS) remain largely unexplored, despite increased recognition of their importance in understanding venom evolution more broadly. Sequencing the transcriptome of venom-producing glands has greatly increased the ability of researchers to examine and characterize the toxin repertoire of small taxa with low venom...
Article
Significance Why biological complexity evolves is a major question in the life sciences, but the specific selection pressures favoring simple or complex traits remain unclear. Using high-resolution measurements of venom complexity in North American pitvipers, we link changes in complexity to natural history via phylogenetic diversity of snake diets...
Article
Motivation Next-generation sequencing has become exceedingly common and has transformed our ability to explore nonmodel systems. In particular, transcriptomics has facilitated the study of venom and evolution of toxins in venomous lineages; however, many challenges remain. Primarily, annotation of toxins in the transcriptome is a laborious and time...
Poster
Full-text available
Most research on snake venoms has focused on front-fanged snake families. However, venomics has now led to the general acceptance of venom being a much more broadly possessed trait within snakes, including species traditionally considered harmless. Due to this historical inertia, the toxin repertoire of rear-fanged snake families, particularly in t...
Poster
Full-text available
Most research on snake venoms has focused on front-fanged snake families. However, venomics has now led to the general acceptance of venom being a much more broadly possessed trait within snakes, including species traditionally considered harmless. Due to this historical inertia, the toxin repertoire of rear-fanged snake families, particularly in t...
Article
Significance A central question in biology is whether trait differences are the result of variation in gene number, sequence, or regulation. Snake venoms are an excellent system for addressing this question because of their genetic tractability, contributions to fitness, and high evolutionary rates. We sequenced and assembled the genome of the Tige...
Article
Full-text available
The migration-selection balance often governs the evolution of lineages, and speciation with gene flow is now considered common across the tree of life. Ecological speciation is a process that can facilitate divergence despite gene flow due to strong selective pressures caused by ecological differences; however, the exact traits under selection are...
Article
Novel phenotypes are commonly associated with gene duplications and neofunctionalization, less documented are the cases of phenotypic maintenance through the recruitment of novel genes. Proteolysis is the primary toxic character of many snake venoms, and ADAM metalloproteinases, named Snake Venom Metalloproteinases (SVMPs), are largely recognized a...
Article
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Background: Modularity is the tendency for systems to organize into semi-independent units and can be a key to the evolution and diversification of complex biological systems. Snake venoms are highly variable modular systems that exhibit extreme diversification even across very short time scales. One well-studied venom phenotype dichotomy is a tra...
Article
New world coralsnakes of the genus Micrurus are a diverse radiation of highly venomous and brightly colored snakes that range from North Carolina to Argentina. Species in this group have played central roles in developing and testing hypotheses about the evolution of mimicry and aposematism. Despite their diversity and prominence as model systems,...
Article
Traits can evolve rapidly through changes in gene expression or protein-coding sequences. However, these forms of genetic variation can be correlated and changes to one can influence the other. As a result,we might expect traits lacking differential expression to preferentially evolve through changes in protein sequences or morphological adaptation...
Article
Front cover: The cover image is based on the Research Paper Reticulate evolution in nuclear Middle America causes discordance in the phylogeny of palm‐pitvipers (Viperidae: Bothriechis) by Andrew J. Mason et al., DOI: 10.1111/jbi.13542. Image Credit: Andrew J. Mason, Clemson University.
Article
Aim A number of processes can lead to weak or conflicting phylogenetic signals, especially in geographically dynamic regions where unstable landscapes and climates promote complex evolutionary histories. The Middle American pitviper genus Bothriechis has a complex biogeographic distribution and previous phylogenetic analyses have recovered conflict...
Article
Full-text available
Snake venoms represent an enriched system for investigating the evolutionary processes that lead to complex and dynamic trophic adaptations. It has long been hypothesized that natural selection may drive geographic variation in venom composition, yet previous studies have lacked the population genetic context to examine these patterns. We leverage...
Article
Full-text available
Ontogenetic changes in venom composition have important ecological implications due the relevance of venom in prey acquisition and defense. Additionally, intraspecific venom variation has direct medical consequences for the treatment of snakebite. However, ontogenetic changes are not well documented in most species. The Mexican Black-tailed Rattles...
Article
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Changes in gene expression can rapidly influence adaptive traits in the early stages of lineage diversification. Venom is an adaptive trait comprised of numerous toxins used for prey capture and defense. Snake venoms can vary widely between conspecific populations, but the influence of lineage diversification on such compositional differences are u...
Article
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Barrier island taxa provide an opportunity to investigate recent evolutionary processes, such as colonization and isolation of recently diverged taxa, and provide important insights into understanding contemporary diversity and the assessment of conservation units. Using rapidly evolving genetic markers (mitochondrial DNA and microsatellites), we s...
Article
Accurate representation of lineage diversity through complete taxon sampling is crucial to understanding the evolution of biodiversity, particularly when using molecular phylogenetics to estimate evolutionary relationships. In this interest, taxonomic diversity is often used as a proxy for lineage diversity even though the two concepts are not syno...
Article
Full-text available
Venom-gland transcriptomics is a key tool in the study of the evolution, ecology, function, and pharmacology of animal venoms. In particular, gene-expression variation and coding sequences gained through transcriptomics provide key information for explaining functional venom variation over both ecological and evolutionary timescales. The accuracy a...
Article
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Small populations resulting from the impacts of habitat fragmentation are prone to increased risks of extinction because of a lack of population connectivity. Roads increase habitat fragmentation, but properly managed roadsides may be able to function as wildlife corridors. Here we use radiotelemetry to observe movement patterns of Gopher Tortoises...
Article
The Mojave rattlesnake (Crotalus scutulatus) inhabits deserts and arid grasslands of the western United States and Mexico. Despite considerable interest in its highly toxic venom and the recognition of two subspecies, no molecular studies have characterized range-wide genetic diversity and population structure or tested species limits within C. scu...
Article
Coastal ecosystems worldwide are being impacted by sea-level rise caused by climate change. As mitigation efforts increase to protect these threatened ecosystems, a deeper understanding of how wildlife adapt to coastal management techniques is needed. We monitored three constructed sand dunes (built in 2010 and 2014) and two natural dunes in centra...
Article
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Background: Staphylococcus aureus has strong association with anthropogenic environments. This association has not been well supported by use of genetic tools. The aim of this study was to phylogenetically relate numerous isolates from three environments - NCBI samples from hospitals, a community, and a previously unexplored healthcare environment...
Article
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Phenotypic diversity generated through altered gene expression is a primary mechanism facilitating evolutionary response in natural systems. By linking the phenotype to genotype through transcriptomics, it is possible to determine what changes are occurring at the molecular level. High phenotypic diversity has been documented in rattlesnake venom,...
Article
Full-text available
Habitat fragmentation is one of the leading causes of biodiversity decline and most commonly results from urbanization and construction of transportation infrastructure. Roads are known to negatively impact species, but railways can often cause similar effects. Certain taxa, such as turtles and tortoises, are more vulnerable to railways than others...
Article
Full-text available
Rattlesnake venoms may be classified according to the presence/absence and relative abundance of the neurotoxic phospholipases A 2 s (PLA 2 s), such as Mojave toxin, and snake venom metalloproteinases (SVMPs). In Mexico, studies to determine venom variation in Mojave Rattlesnakes (Crotalus scutulatus scutulatus) are limited and little is known abou...
Article
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The uplift and final connection of the Central American land bridge is considered the major event that allowed biotic exchange between vertebrate lineages of northern and southern origin in the New World. However, given the complex tectonics that shaped Middle America, there is still substantial controversy over details of this geographical reconne...
Data
Specimens examined. Accession Numbers With Asterisks Are Sequences Obtained Of GeneBank. (DOCX)
Article
Full-text available
The use of game cameras by wildlife biologists and managers to survey wildlife, particularly medium-and large-bodied mammals, has increased dramatically. Previous attempts to survey small mammals and ectotherms have had limited detection success or were focused solely on a single species. We describe the Adapted-Hunt Drift Fence Technique (AHDriFT)...
Article
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Sea-level rise due to climate change is a major threat to coastal ecosystems worldwide. Current management to reduce beach erosion often focuses on protecting human structures and research on effects on wildlife is lacking. Using a combination of hierarchical models and generalized linear models, we evaluated how the gopher tortoise (Gopherus polyp...
Article
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Middle America is one of the most biodiverse regions in the world, harboring an exceptional number of rare and endemic species. This is especially true of Middle American cloud forests, where montane specialists occupy restricted, high-elevation ranges making them attractive candidates for investigating historical biogeography and speciation. One s...
Conference Paper
Full-text available
This paper details the use of evidence based practices in a strategic effort to recruit, and then retain, undecided admits into a science, technology, engineering and mathematics (STEM) learning community designed to increase student success in STEM and, ultimately, the number of STEM degrees awarded. The primary goal of the National Science Founda...
Article
Strong spatial sorting of genetic variation in contiguous populations is often explained by local adaptation or secondary contact following allopatric divergence. A third explanation, spatial sorting by stochastic effects of range expansion, has been considered less often though theoretical models suggest it should be widespread, if ephemeral. In a...
Article
The venomous snake subfamily Hydrophiinae includes more than 40 genera and approximately 200 species. Most members of this clade inhabit Australia, and have been well studied. But, because of poor taxon sampling of Melanesian taxa, basal evolutionary relationships have remained poorly resolved. The Melanesian genera Ogmodon, Loveridgelaps, and Salo...
Article
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The Cottonmouth, Agkistrodon piscivorus, is a semi-aquatic pitviper that occupies the southeastern U.S. west into Texas. Several previous studies have investigated the biogeographic history of A. piscivorus. It has been hypothesized that A. piscivorus was split into two separate populations during the last glacial maximum and climate change has imp...
Article
Full-text available
Background Staphylococcus aureus (SA) nasal colonization plays a critical role in the pathogenesis of staphylococcal infections and SA eradication from the nares has proven to be effective in reducing endogenous infections. To understand SA nasal colonization and its relation with consequent disease, assessment of nasal carriage dynamics and genoty...
Article
Full-text available
Anthropogenic habitat loss is among the greatest threats to biodiversity. Populations undergoing fragmentation and loss of habitat are also threatened by erosion of genetic diversity. However, contemporary genetic diversity may be the legacy of natural processes acting prior to anthropogenic influences. Measurements of genetic diversity from contem...
Article
Full-text available
Estimates of relationships among Staphylococcus species have been hampered by poor and inconsistent resolution of phylogenies based largely on single gene analyses incorporating only a limited taxon sample. As such, the evolutionary relationships and hierarchical classification schemes among species have not been confidently established. Here, we a...
Data
Full-text available
Bayesian inferences of phylogeny are highly reproducible, regardless of model employed. Shown are plots of post-burnin generational log likelihoods (lnL) from five representative partitioning strategies across triplicate concatenated BI runs (A); and duplicate BEST runs (B). All runs were highly reproducible regardless of methodology and partitioni...
Data
Full-text available
Model partitioning increases the mean tree length (TL) and run variance. Shown is a box plot indicating the mean TL and 95% confidence interval among partitioning strategies.
Data
Full-text available
Inference of phylogeny using Bayesian estimation of species trees (BEST). Shown is a consensus phylogram of the staphylococcal species tree generated using all four gene fragments under the BEST methodology. Each gene fragment was treated as an individual locus for which individual gene trees were estimated (similar to MB3). Numbers represent poste...
Data
Full-text available
Gene trees for individual loci assessed in this study. Shown are Bayesian 50% majority rule phylograms for A) the 16S rRNA, B) dnaJ, C) rpoB, and D) tuf gene fragments. MrBayes was run under the same conditions as those used for concatenated analyses with evolutionary model specified for whole gene fragments in Additional file 2: Table S2. Numbers...
Data
Full-text available
Tree length (TL) analysis indicates that overparameterization may be occurring within more highly partitioned datasets. Shown are post-burnin generational TL estimates for partitioning strategies assessed in this study. Note that as the complexity of partitioning increases evidence of increased TL and failed convergence is observed.
Data
Full-text available