56 results on '"Smith, Eric N."'
Search Results
2. Observation of suppressed viscosity in the normal state of 3 He due to superfluid fluctuations.
- Author
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Baten RN, Tian Y, Smith EN, Mueller EJ, and Parpia JM
- Abstract
Evidence of fluctuations in transport have long been predicted in
3 He. They are expected to contribute only within 100μK of Tc and play a vital role in the theoretical modeling of ordering; they encode details about the Fermi liquid parameters, pairing symmetry, and scattering phase shifts. It is expected that they will be of crucial importance for transport probes of the topologically nontrivial features of superfluid3 He under strong confinement. Here we characterize the temperature and pressure dependence of the fluctuation signature, by monitoring the quality factor of a quartz tuning fork oscillator. We have observed a fluctuation-driven reduction in the viscosity of bulk3 He, finding data collapse consistent with the predicted theoretical behavior., (© 2023. Springer Nature Limited.)- Published
- 2023
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3. Evaluation of the "rethink stress" mindset intervention: A metacognitive approach to changing mindsets.
- Author
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Crum AJ, Santoro E, Handley-Miner I, Smith EN, Evans K, Moraveji N, Achor S, and Salovey P
- Subjects
- Humans, Metacognition, Stress, Psychological psychology, Stress, Psychological therapy
- Abstract
Experimental research has demonstrated that a stress-is-enhancing mindset can be induced and can improve outcomes by presenting information on the enhancing nature of stress. However, experimental evidence, media portrayals, and personal experience about the debilitating nature of stress may challenge this mindset. Thus, the traditional approach of focusing on the more "desired" mindset without arming participants against encounters with the less desired mindsets may not be sustainable in the face of conflicting information. How might this limitation be resolved? Here, we present three randomized-controlled interventions that test the efficacy of a "metacognitive approach." In this approach, participants are given more balanced information about the nature of stress along with metacognitive information on the power of their mindsets aimed at empowering them to choose a more adaptive mindset even in the face of conflicting information. In Experiment 1, employees of a large finance company randomized to the metacognitive mindset intervention reported greater increases in stress-is-enhancing mindsets and greater improvements in self-reported measures of physical health symptoms and interpersonal-skill work performance 4 weeks later compared to a waitlist control. Experiment 2, adapted to be distributed electronically via multimedia modules, replicates the effects on stress mindset and symptoms. Experiment 3 compares the metacognitive stress mindset intervention with a more traditional stress mindset manipulation. The metacognitive approach led to greater initial increases in a stress-is-enhancing mindset relative to the traditional intervention, and these increases were sustained after exposure to contradictory information. Taken together, these results provide support for a metacognitive approach to mindset change. (PsycInfo Database Record (c) 2023 APA, all rights reserved).
- Published
- 2023
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4. Unveiling underestimated species diversity within the Central American Coralsnake, a medically important complex of venomous taxa.
- Author
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Jowers MJ, Smart U, Sánchez-Ramírez S, Murphy JC, Gómez A, Bosque RJ, Sarker GC, Noonan BP, Faria JF, Harris DJ, da Silva NJ Jr, Prudente ALC, Weber J, Kok PJR, Rivas GA, Jadin RC, Sasa M, Muñoz-Mérida A, Moreno-Rueda G, and Smith EN
- Subjects
- United States, Phylogeny, Central America, Panama, Mexico, Venoms
- Abstract
Coralsnakes of the genus Micrurus are a diverse group of venomous snakes ranging from the southern United States to southern South America. Much uncertainty remains over the genus diversity, and understanding Micrurus systematics is of medical importance. In particular, the widespread Micrurus nigrocinctus spans from Mexico throughout Central America and into Colombia, with a number of described subspecies. This study provides new insights into the phylogenetic relationships within M. nigrocinctus by examining sequence data from a broad sampling of specimens from Mexico, Guatemala, Honduras, Nicaragua, Costa Rica, and Panama. The recovered phylogenetic relationships suggest that M. nigrocinctus is a species complex originating in the Pliocene and composed of at least three distinct species-level lineages. In addition, recovery of highly divergent clades supports the elevation of some currently recognized subspecies to the full species rank while others may require synonymization., (© 2023. The Author(s).)
- Published
- 2023
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5. Where and with whom does a brief social-belonging intervention promote progress in college?
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Walton GM, Murphy MC, Logel C, Yeager DS, Goyer JP, Brady ST, Emerson KTU, Paunesku D, Fotuhi O, Blodorn A, Boucher KL, Carter ER, Gopalan M, Henderson A, Kroeper KM, Murdock-Perriera LA, Reeves SL, Ablorh TT, Ansari S, Chen S, Fisher P, Galvan M, Gilbertson MK, Hulleman CS, Le Forestier JM, Lok C, Mathias K, Muragishi GA, Netter M, Ozier E, Smith EN, Thoman DB, Williams HE, Wilmot MO, Hartzog C, Li XA, and Krol N
- Subjects
- Humans, Universities, Random Allocation, Psychosocial Intervention, Students psychology, Social Identification, Achievement
- Abstract
A promising way to mitigate inequality is by addressing students' worries about belonging. But where and with whom is this social-belonging intervention effective? Here we report a team-science randomized controlled experiment with 26,911 students at 22 diverse institutions. Results showed that the social-belonging intervention, administered online before college (in under 30 minutes), increased the rate at which students completed the first year as full-time students, especially among students in groups that had historically progressed at lower rates. The college context also mattered: The intervention was effective only when students' groups were afforded opportunities to belong. This study develops methods for understanding how student identities and contexts interact with interventions. It also shows that a low-cost, scalable intervention generalizes its effects to 749 4-year institutions in the United States.
- Published
- 2023
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6. A new species of Dipsas (Serpentes, Dipsadidae) from central Panama.
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Ray JM, Sánchez-Martínez P, Batista A, Mulcahy DG, Sheehy Iii CM, Smith EN, Pyron RA, and Arteaga A
- Abstract
A new species of Dipsas Laurenti, 1768, from Central Panama is described based on molecular analyses, hemipenial morphology, and external characters. This is the sixth species of Dipsas to be described for the country; the snake has been suspected to exist since 1977 and has not been thoroughly studied until now. Additionally, morphological comparations including scale counts are done with other species within the genus, and the current geographic distribution of Dipsastemporalis (Werner, 1909), the sister species, is updated. Finally, a key to the species of Dipsas currently known from Middle America is presented., (Julie M. Ray, Paola Sánchez-Martínez, Abel Batista, Daniel G. Mulcahy, Coleman M. Sheehy III, Eric N. Smith, R. Alexander Pyron, Alejandro Arteaga.)
- Published
- 2023
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7. Phylogeographic inference of Sumatran ranids bearing gastromyzophorous tadpoles with regard to the Pleistocene drainage systems of Sundaland.
- Author
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Arifin U, Smart U, Husemann M, Hertwig ST, Smith EN, Iskandar DT, and Haas A
- Subjects
- Animals, Anura genetics, Larva genetics, Phylogeny, Phylogeography, Biodiversity, Biological Evolution
- Abstract
Rivers are known to act as biogeographic barriers in several strictly terrestrial taxa, while possibly serving as conduits of dispersal for freshwater-tolerant or -dependent species. However, the influence of river systems on genetic diversity depends on taxa-specific life history traits as well as other geographic factors. In amphibians, several studies have demonstrated that river systems have only minor influence on their divergence. Here, we assess the role of the paleodrainage systems of the Sunda region (with a focus on the island of Sumatra) in shaping the evolutionary history of two genera of frogs (Sumaterana and Wijayarana) whose tadpoles are highly dependent on cascading stream habitats. Our phylogenetic results show no clear association between the genetic diversification patterns of both anurans genera and the existence of paleodrainage systems. Time-calibrated phylogenies and biogeographical models suggest that these frogs colonized Sumatra and diversified on the island before the occurrence of the Pleistocene drainage systems. Both genera demonstrate phylogenetic structuring along a north-south geographic axis, the temporal dynamics of which coincide with the geological chronology of proto Sumatran and -Javan volcanic islands. Our results also highlight the chronic underestimation of Sumatran biodiversity and call for more intense sampling efforts on the island., (© 2022. The Author(s).)
- Published
- 2022
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8. A new species of Sceloporus of the torquatus group (Reptilia: Phrynosomatidae) from West Mexico.
- Author
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Flores-Villela O, Smith EN, Campillo-Garca G, Martnez-Mndez N, and Campbell JA
- Subjects
- Animals, Mexico, Lizards genetics
- Abstract
We describe Sceloporus huichol sp. nov., a new species of spiny lizard of the genus Sceloporus, that is found in the mountainous regions of Jalisco and Nayarit in western Mexico. The new species belongs to the torquatus species group and has previously been confused with Sceloporus melanogaster, from which it differs by its smaller size, head color and nuchal collar. Additionally, Sceloporus huichol sp. nov. is different from the rest of its congeners by relevant genetic and morphologicall data. Despite having a complete nuchal collar, characteristic of Sceloporus torquatus, S. huichol sp. nov. is more closely related phylogenetically to S. melanogaster. Recognition of this new species brings the number of species in the torquatus group to nine.
- Published
- 2022
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9. Two new species of Megophrys Kuhl and Van Hasselt (Amphibia: Megophryidae) from Sumatra, Indonesia.
- Author
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Munir M, Nishikawa K, Hamidy A, and Smith EN
- Subjects
- Animals, Geography, Indonesia, Phylogeny, Anura genetics
- Abstract
We evaluated the taxonomic status of the genus Megophrys in Sumatra using molecular and morphological data. Mitochondrial phylogenetic inference and morphological data revealed two undescribed species, one in southern SumatraM. selatanensis sp. nov. and one in northern SumatraM. acehensis sp. nov. We also detected a potential cryptic species within M. parallela, but refrain from describing this lineage here due to insufficient data. Genetic variation within Sumatran Megophrys is highly structured and will require additional geographic sampling to understand the interplay between geography and genetics in Sumatran Megophrys.
- Published
- 2021
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10. A tiny new species of Microhyla Tschudi, 1838 (Amphibia: Anura: Microhylidae) from Belitung Island and Southeastern Sumatra, Indonesia.
- Author
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Eprilurahman R, Garg S, Atmaja VY, Alhadi F, Munir M, Ubaidillah R, Arisuryanti T, Biju SD, Smith EN, and Hamidy A
- Subjects
- Animals, Indonesia, Male, Phylogeny, RNA, Ribosomal, 16S genetics, Anura genetics, Forests
- Abstract
A tiny new species of narrow-mouthed frog of the genus Microhyla is described from the island of Belitung and southeastern Sumatra, Indonesia. The most distinctive feature of the new frog is its diminutive adult size, snout-vent length ranging only from 12.3 to 15.8 mm in adult males. Phylogenetic analyses based a fragment of the mitochondrial 16S rRNA gene, along with detailed morphological and acoustic comparison differentiate the new taxon from all known congeners. The new species, formally described as Microhyla sriwijaya sp. nov., is a member of the M. achatina species group and the sister taxon to M. orientalis. It is diagnosable from other congeners by a combination of characters: (1) smaller male snout-vent size 16 mm; (2) snout obtusely rounded in dorsal view; (3) absence of mid-dorsal line and skin fold; (4) first finger reduced (finger I length less than half of finger II length); (5) dorsum with a prominent dark median mark extending posteriorly, narrow anteriorly near the level of the shoulder and expanding dorsolaterally up to the vent; margins of the dorsal marking concave with broad reddish-brown or orange colouration on either side; (6) foot webbing rudimentary, reaching just up to the first subarticular tubercle on all toes; (7) dorsal skin with prominent tubercles, especially in life; (8) tibiotarsal articulation of adpressed limb reaching beyond the snout tip; and (9) males produce a single type of call with pulsatile temporal structure, calls of relatively short duration ranging between 31.862.8 s, with two to three pulses delivered at a rate ranging between 32.236.0 pulses per second, and the mean overall dominant frequency of 4.3 kHz. The uncorrected pairwise genetic distances between Microhyla sriwijaya sp. nov. and all other known congeners are > 3.8% for the studied 16S gene fragment. The new species was discovered from wayside rural areas with oil palm plantations at four localities in the small island of Belitung (type locality), and from coffee plantation and secondary forest at Lampung in southeastern Sumatra. It is not known from any protected area and appears to be threatened due to tin mining activity, intensive logging, oil palm, and other commonly practiced agriculture activities.
- Published
- 2021
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11. A new species of Oreosaurus (Squamata: Gymnophthalmidae) from the Turimiquire Massif, northeastern Venezuela.
- Author
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Rivas GA, Nunes PMS, Baran A, Jowers MJ, Smith EN, Hernndez-Morales C, and Schargel WE
- Subjects
- Animal Distribution, Animals, Venezuela, Lizards
- Abstract
We describe a new species of gymnophthalmid lizard, Oreosaurus bisbali sp. nov., from the Turimiquire Massif in northeastern Venezuela. It is one of three reptile species known to be endemic to the region and the fifth species of Oreosaurus from Venezuela. It can be distinguished from all congeners by a combination of rectangular dorsal scales at midbody, having two scales separating femoral pores medially, and lacking a nasoloreal suture. The new species is likely to be restricted in distribution to the highlands of the Turimiquire Massif, which have been significantly degraded by agriculture.
- Published
- 2021
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12. Hidden in the plain sight: a new species of Rhabdophis (Serpentes: Natricinae) from the Rhabdophis himalayanus complex.
- Author
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DAS A, Smith EN, Sidik I, Sarker GC, Boruah B, Patel NG, Murthy BHCK, and Deepak V
- Subjects
- Animals, Forests, Colubridae
- Abstract
A new species of natricine snake of the genus Rhabdophis is described from Northeast India. Morphologically the new species is similar to Rhabdophis himalayanus but it can be distinguished from it by lacking a nuchal groove and nuchal glands, being relatively smaller, and having a distinct neck, ventral, and subcaudal coloration. In overall coloration it resembles R. chrysargos, from which it is distinguished by several aspects of its morphology and genetic differences. The discovery of Rhabdophis bindi sp. nov. reveals that forested regions in the northeastern part of India needs further biological exploration.
- Published
- 2021
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13. Possible osteosarcoma reported from a new world elapid snake and review of reptilian bony tumors.
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Hall AS, Jacobs JL, and Smith EN
- Subjects
- Animals, Bone Neoplasms pathology, Osteosarcoma pathology, Bone Neoplasms veterinary, Coral Snakes, Osteosarcoma veterinary
- Abstract
Cancer chiefly occurs in vertebrates. Rare in amphibians, and perhaps common in reptiles, various neoplasms and malignant cancers have been reported with erratic frequency by museums, paleontologists, veterinarians, and pet hobbyists. Unsurprisingly, most herpetofaunal diversity has never been systematically surveyed for the presence of neoplasms owing to the extreme rarity or obscurity of many species. Museum collections can fill these gaps in knowledge, especially when researchers use non-destructive techniques. In this study, we used X-ray computed tomography (CT) to discover and characterize a possible osteosarcoma of the spine in a rare South American coralsnake, Micrurus ancoralis. Two spinal vertebrae were completely fused and adjacent vertebrae showed evidence of corruption. The fused vertebrae contained a hollow inner network thought to be vascular tissue. We also review previous reports of neoplasms in the Elapidae and all bony neoplasms in non-avian reptiles. The rarely reported technique of X-ray CT for tumor discovery could greatly improve our understanding of the species diversity and perhaps underlying causes of neoplasia., (© 2020 American Association for Anatomy.)
- Published
- 2020
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14. Phylogeny and biogeography of Sumatra´s cloud forest lizards of the genus Dendragama and status of Acanthosaura schneideri .
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Shaney KJ, Harvey MB, Hamidy A, Kurniawan N, and Smith EN
- Abstract
Lizards of the genus Dendragama are endemic to the highland cloud forests of Sumatra's Barisan Mountain Range in western Indonesia, and recent studies have uncovered widespread diversity within the genus. Here, a suite of morphological characters and mitochondrial DNA are used to compare three geographically isolated populations of D. boulengeri from (1) Mount Kerinci in Jambi province, (2) Mount Marapi of west Sumatra, and (3) the Karo Highlands of north Sumatra. Additional phylogeographic analyses with two recently described sister species, D. australis and D. dioidema were conducted. Five genetically distinct clades of Dendragama , all distributed allopatrically of one another were identified and some are suspected to inhabit small distributions. Morphological and genetic data confirm the Karo Highlands population D. schneideri (previously Acanthosaura schneideri Ahl, 1926) should be revalidated from the synonymy of D. boulengeri . Dendragama schneideri is endemic to montane forests of the Karo Highlands surrounding Lake Toba in Sumatra Utara province. Pairwise genetic distances of 6-11% separate D. schneideri from congeners. Two distinct clades of D. boulengeri from Mount Kerinci and Mount Marapi were identified, which are 5.0% genetically distant from one another. Using morphological characters, we provide the first key for distinguishing between species of Dendragama . Based on biogeographic patterns and levels of genetic variation it is suspected that at least 18 other isolated cloud forest locations may hold new species or divergent populations of Dendragama but lack survey work. Collectively, these comparisons among populations of montane lizards further elucidate the complex biogeographic history of Sumatra's montane forest species and the first phylogeny of the genus Dendragama ., (Kyle J. Shaney, Michael B. Harvey, Amir Hamidy, Nia Kurniawan, Eric N. Smith.)
- Published
- 2020
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15. Taxonomic evaluation of two similar bent-toed geckos Squamata: Gekkonidae: Cyrtodactylus Gray, 1827) from East Java, Indonesia.
- Author
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Riyanto A, Farajallah A, Hamidy A, Fitriana YS, Munir M, Kurniawan N, and Smith EN
- Subjects
- Animals, Color, Ecosystem, Genetic Drift, Indonesia, Male, Lizards
- Abstract
The bent-toed geckos of the genus Cyrtodactylus are the most speciose land vertebrates of Southeast Asia (about 300 species so far) and new species continue to be recognized at a rapid rate. Within the last decade three new species were described from Java, Indonesia, C. semiadii, C. petani, and C. klakahensis. The latter two are very similar, except for differences in the precloacal depression in adult males. These two species have relatively close type localities, separated from each other by only about 50 km, and with similar habitat type and elevation. Our study aimed to evaluate the taxonomic status of C. klakahensis and C. petani using both morphological and genetic evidence. These two species are genetically similar, with a genetic divergence of only 1.5 to 1.6%. This divergence is well below the level of typically characterizes sister species of Cyrtodactylus (approximately 4% in the mitochondrial ND2 gene), and is more in line with population variation due to geographic distance. Further examination of specimens, from both type localities, showed no diagnostic morphological characters between the two species. Thus, we conclude that C. klakahensis and C. petani are conspecific, and following article 23 of the ICZN, C. klakahensis is herein considered a junior synonym of C. petani.
- Published
- 2020
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16. Phylogeography of montane dragons could shed light on the history of forests and diversification processes on Sumatra.
- Author
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Shaney KJ, Maldonado J, Smart U, Thammachoti P, Fujita M, Hamidy A, Kurniawan N, Harvey MB, and Smith EN
- Subjects
- Animals, Gene Flow, Genome, Mitochondrial, Indonesia, Lizards genetics, Phylogeny, Biodiversity, Forests, Lizards classification, Phylogeography
- Abstract
Biogeographical evidence, both, for and against the "regional endemism paradigm" hypothesis has been uncovered across the Greater Sunda Region (Sundaland) of Southeast Asia. Additionally, there are competing hypotheses regarding how Pleistocene forests may have impacted biological patterns and processes in Sumatra. Using montane agamid lizards from Sumatra, we derived and analyzed a phylogenetic dataset, genetic divergence estimates, and contemporary distributional patterns among species. We tested whether (1) Sumatra's highland Draconinae diversification fits the regional endemism paradigm hypothesis and (2) Draconinae phylogeography provides biological evidence for Pleistocene forest extent at various points in history. Our results suggest in situ diversification was the main driver behind montane Draconinae lizard diversification in Sumatra, rejecting the "regional endemism paradigm". Contemporary distribution of endemic species and their genetic relationships may potentially provide biologicalevidence for determining more precise elevational lower limits of montane forests during the Pleistocene epoch. Our data suggests montane forests did not retreat more than 700-750 m during glacial maxima because lower retreating forests would have become interconnected, allowing for widespread dispersal, exchange of gene flow and sympatric distributions contemporarily. To the contrary, our divergence estimates show that cloud forest dragons have been isolated for millions of years, suggesting there may have been a continuous disconnect between some areas, predating the Pleistocene. There may also be other ecological and evolutionary factors that impacted Draconinae distributions, such as competition, making this an excellent system for testing questions regarding montane biogeography. Additionally, we provide the first phylogeny for a wide range of Sundaland agamid species and identify some biogeographic pressures that may have triggered montane Draconinae diversification in Sumatra., (Copyright © 2020 Elsevier Inc. All rights reserved.)
- Published
- 2020
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17. Impacts of the Toba eruption and montane forest expansion on diversification in Sumatran parachuting frogs (Rhacophorus).
- Author
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O'Connell KA, Oaks JR, Hamidy A, Shaney KJ, Kurniawan N, Smith EN, and Fujita MK
- Subjects
- Animals, Bayes Theorem, DNA, Mitochondrial genetics, Forests, Genetic Variation, Indonesia, Phylogeny, Anura genetics, Aviation
- Abstract
Catastrophic events, such as volcanic eruptions, can have profound impacts on the demographic histories of resident taxa. Due to its presumed effect on biodiversity, the Pleistocene eruption of super-volcano Toba has received abundant attention. We test the effects of the Toba eruption on the diversification, genetic diversity, and demography of three co-distributed species of parachuting frogs (Genus Rhacophorus) on Sumatra. We generate target-capture data (~950 loci and ~440,000 bp) for three species of parachuting frogs and use these data paired with previously generated double digest restriction-site associated DNA (ddRADseq) data to estimate population structure and genetic diversity, to test for population size changes using demographic modelling, and to estimate the temporal clustering of size change events using a full-likelihood Bayesian method. We find that populations around Toba exhibit reduced genetic diversity compared with southern populations, and that northern populations exhibit a shift in effective population size around the time of the eruption (~80 kya). However, we infer a stronger signal of expansion in southern populations around ~400 kya, and at least two of the northern populations may have also expanded at this time. Taken together, these findings suggest that the Toba eruption precipitated population declines in northern populations, but that the demographic history of these three species was also strongly impacted by mid-Pleistocene forest expansion during glacial periods. We propose local rather than regional effects of the Toba eruption, and emphasize the dynamic nature of diversification on the Sunda Shelf., (© 2020 John Wiley & Sons Ltd.)
- Published
- 2020
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18. Genome-wide SNPs clarify lineage diversity confused by coloration in coralsnakes of the Micrurus diastema species complex (Serpentes: Elapidae).
- Author
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Reyes-Velasco J, Adams RH, Boissinot S, Parkinson CL, Campbell JA, Castoe TA, and Smith EN
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- Animals, Argentina, Bayes Theorem, Cell Nucleus genetics, DNA, Mitochondrial genetics, Genetic Variation, Genetics, Population, Geography, Likelihood Functions, Nucleotides genetics, Pigmentation genetics, Principal Component Analysis, Species Specificity, Biodiversity, Coral Snakes genetics, Genome, Phylogeny, Polymorphism, Single Nucleotide genetics
- Abstract
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, surprisingly little is known about species boundaries and phylogenetic relationships within Micrurus, which has substantially hindered meaningful analyses of their evolutionary history. Here we use mitochondrial genes together with thousands of nuclear genomic loci obtained via ddRADseq to study the phylogenetic relationships and population genomics of a subclade of the genus Micrurus: The M. diastema species complex. Our results indicate that prior species and species-group inferences based on morphology and color pattern have grossly misguided taxonomy, and that the M. diastema complex is not monophyletic. Based on our analyses of molecular data, we infer the phylogenetic relationships among species and populations, and provide a revised taxonomy for the group. Two non-sister species-complexes with similar color patterns are recognized, the M. distans and the M. diastema complexes, the first being basal to the monadal Micrurus and the second encompassing most North American monadal taxa. We examined all 13 species, and their respective subspecies, for a total of 24 recognized taxa in the M. diastema species complex. Our analyses suggest a reduction to 10 species, with no subspecific designations warranted, to be a more likely estimate of species diversity, namely, M. apiatus, M. browni, M. diastema, M. distans, M. ephippifer, M. fulvius, M. michoacanensis, M. oliveri, M. tener, and one undescribed species., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)
- Published
- 2020
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19. The roles of vicariance and dispersal in the differentiation of two species of the Rhinella marina species complex.
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Bessa-Silva A, Vallinoto M, Sampaio I, Flores-Villela OA, Smith EN, and Sequeira F
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- Animals, Bayes Theorem, Biological Evolution, Bufo marinus genetics, Central America, Cytochromes b chemistry, Cytochromes b classification, Cytochromes b genetics, DNA, Mitochondrial genetics, Gene Flow, Genetic Variation, Microsatellite Repeats genetics, Phylogeny, Phylogeography, Ribosomal Proteins chemistry, Ribosomal Proteins classification, Ribosomal Proteins genetics, South America, Bufo marinus classification
- Abstract
The high levels of Neotropical biodiversity are commonly associated with the intense Neogene-Quaternary geological events and climate dynamics. Here, we investigate the evolutionary history of two species of Neotropical closely related amphibians (R. horribilis and R. marina). We combine published data with new mitochondrial DNA sequences and multiple nuclear markers, including 12 microsatellites. The phylogenetic analyses showed support for grouping the samples in two main clades; R. horribilis (Central America and Mexico) and R. marina (South America east of the Andes). However, the phylogenetic inferences also show an evident mito-nuclear discordance. We use Approximate Bayesian Computation (ABC) to test the role of different events in the diversification between the two groups recovered. We found that both species were affected primarily by a recent Pleistocene divergence, which was similar to the divergence estimate revealed by the Isolation-with-Migration model, under persistent bidirectional gene flow through time. We provide the first evidence that R. horribilis is differentiated from the South American R. marina at the nuclear level supporting the taxonomic status of R. horribilis, which has been controversial for more than a century., (Copyright © 2019 Elsevier Inc. All rights reserved.)
- Published
- 2020
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20. Stress, Mindsets, and Success in Navy SEALs Special Warfare Training.
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Smith EN, Young MD, and Crum AJ
- Abstract
Mindsets can impact an individual's performance in stressful experiences such as public speaking or receiving negative feedback. Yet we know little about the boundary conditions of where these mindsets predict success, and where they may become irrelevant or even maladaptive. The current research asks whether mindsets are beneficial in environments of extreme physical and mental stress using participants undergoing the notoriously challenging Navy SEALs training. We hypothesized that participants with stress-is-enhancing mindsets - who believe stress enhances their health, performance and wellbeing - will outperform those with stress-is-debilitating mindsets. In addition, we explore whether other mindsets about willpower and failure predict success in a similar manner. Following 174 Navy SEALs candidates, we find that, even in this extreme setting, stress-is-enhancing mindsets predict greater persistence through training, faster obstacle course times, and fewer negative evaluations from peers and instructors. We also find evidence that failure-is-enhancing mindsets may be detrimental to candidates' success, and non-limited willpower mindsets prompt negative evaluations from others. Multiverse analyses were conducted to test for the robustness of these effects across researcher analytical decisions, which produced consistent results. We discuss how findings in this unique environment can provide insight into the importance of mindsets in other organizations and propose future avenues of research to further understand the causal role of mindsets in diverse workplace contexts., (Copyright © 2020 Smith, Young and Crum.)
- Published
- 2020
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21. New species, diversity, systematics, and conservation assessment of the Puppet Toads of Sumatra (Anura: Bufonidae: Sigalegalephrynus).
- Author
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Sarker GC, Wostl E, Thammachoti P, Sidik I, Hamidy A, Kurniawan N, and Smith EN
- Subjects
- Animals, Endangered Species, Indonesia, Phylogeny, Anura, Bufonidae
- Abstract
Using a combination of morphological and molecular data we recognize three new species of Puppet Toad, Sigalegalephrynus Smart, Sarker, Arifin, Harvey, Sidik, Hamidy, Kurniawan Smith, a recently described genus endemic to the highland forests of Sumatra, Indonesia. Phylogenetic analysis of mitochondrial DNA sequences recovered a monophyletic relationship among all Puppet Toads, with two distinct evolutionary clades, a northern and a southern. The northern clade includes Sigalegalephrynus gayoluesensis sp. nov., and S. burnitelongensis sp. nov., and the southern clade includes S. harveyi sp. nov., S. mandailinguensis, and S. minangkabauensis. With the discovery of these three new species, Sigalegalephrynus contains more endemic species than any other genus of toad in Indonesia. We used maximum entropy, implemented in MaxEnt, to identify suitable habitats and occurrence probability of additional undescribed new species from the island. The most important predictors of Sigalegalephrynus distribution were elevation (64.5%) and land cover (7.11%). Based on the probability of presence, it is likely that there are many more species of the genus awaiting discovery in Sumatra. Our analysis, based on IUCN Red List of Threatened Species category and criteria, shows that all of the five species of Sigalegalephrynus are in great risk of extinction and should be placed into the Endangered (EN) category of IUCN Red List.
- Published
- 2019
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22. A new species of Micryletta frog (Microhylidae) from Northeast India.
- Author
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Das A, Garg S, Hamidy A, Smith EN, and Biju SD
- Abstract
We describe a new species of frog in the microhylid genus Micryletta Dubois, 1987 from Northeast India based on molecular and morphological evidence. The new species, formally described as Micryletta aishani sp. nov., is phenotypically distinct from other congeners by a suite of morphological characters such as brown to reddish-brown dorsum; dorsal skin shagreened with minute spinules; snout shape nearly truncate in dorsal and ventral view; a prominent dark streak extending from tip of the snout up to the lower abdomen; ash-grey mottling along the margins of upper and lower lip extending up to the flanks, limb margins and dorsal surfaces of hand and foot; tibiotarsal articulation reaching up to the level of armpits; absence of outer metatarsal tubercles; and absence of webbing between toes. Phylogenetic relationships within the genus are inferred based on mitochondrial data and the new taxon is found to differ from all the recognised Micryletta species by 3.5-5.9% divergence in the mitochondrial 16S rRNA. The new species was found in the states of Assam, Manipur, and Tripura, from low to moderate elevation (30-800 m asl) regions lying south of River Brahmaputra and encompassing the Indo-Burma Biodiversity Hotspot. The discovery validates the presence of genus Micryletta in Northeast India based on genetic evidence, consequently confirming the extension of its geographical range, westwards from Southeast Asia up to Northeast India. Further, for nomenclatural stability of two previously known species, Microhyla inornata (= Micryletta inornata ) and Microhyla steinegeri (= Micryletta steinegeri ), lectotypes are designated along with detailed descriptions., Competing Interests: The authors declare that they have no competing interests.
- Published
- 2019
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23. Rediscovery of Micryletta inornata (Boulenger, 1890) from Sumatra: redescription, molecular identity, and taxonomic implications.
- Author
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Alhadi F, Hamidy A, Farajallah A, Munir M, Atmaja VY, Garg S, Biju SD, and Smith EN
- Subjects
- Animals, China, India, Indonesia, Islands, Malaysia, Phylogeny, RNA, Ribosomal, 16S, Taiwan, Anura genetics
- Abstract
Micryletta inornata (Boulenger 1890), the type species of the genus Micryletta, was originally described from the island of Sumatra in Indonesia. Subsequently, this species has been widely reported from Sundaland (Sumatra and Malay Peninsula), Indo-China, Northeast India and South Andaman, up to southern China and Taiwan. However, since the original description there has been no further report of this species from the type locality or the island. During a herpetofaunal survey in Sumatra, several specimens that are morphologically concordant with the original description and the syntypes of M. inornata were found, and thus the species was rediscovered after 125 years. Here, we provide a redescription of the species based on the freshly collected specimens, along with a detailed morphological and molecular comparison with known congeners. Further, using molecular data from the mitochondrial 16S rRNA gene, our study recovered the Sumatran M. inornata as a phylogenetically distinct lineage from all other populations previously referred to this species. This confirms that all known Micryletta 'inornata' populations from regions outside Sumatra constitute several other lineages representing either new species or previously available names currently considered as synonyms, consequently requiring taxonomic validation in the future.
- Published
- 2019
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24. Diversification of bent-toed geckos (Cyrtodactylus) on Sumatra and west Java.
- Author
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O'Connell KA, Smart U, Sidik I, Riyanto A, Kurniawan N, and Smith EN
- Subjects
- Animals, Bayes Theorem, Calibration, Fossils, Geography, Indonesia, Islands, Likelihood Functions, Phylogeny, Species Specificity, Biodiversity, Lizards classification
- Abstract
Complex geological processes often drive biotic diversification on islands. The islands of Sumatra and Java have experienced dramatic historical changes, including isolation by marine incursions followed by periodic connectivity with the rest of Sundaland across highland connections. To determine how this geological history influenced island invasions, we investigated the colonization history and diversification of bent-toed geckos (genus Cyrtodactylus) on Sumatra and west Java. We used mitochondrial and nuclear sequence data to explore species boundaries, estimate phylogenetic relationships and divergence times, and to reconstruct ancestral range evolution. We found that Sumatran and Javan Cyrtodactylus were closely related to species from the Thai-Malay Peninsula, rather than from Borneo, and that Cyrtodactylus most likely dispersed to Sumatra three times during the late Oligocene and early Miocene. Similarly, Cyrtodactylus invaded west Java from Sumatra once in the early Miocene. Our results suggest that despite isolation by marine incursions during much of the Miocene, Cyrtodactylus dispersed to and from Sumatra and west Java likely via land bridges, and that in situ diversification occurred several times on Sumatra., (Copyright © 2019 Elsevier Inc. All rights reserved.)
- Published
- 2019
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25. The effect of missing data on coalescent species delimitation and a taxonomic revision of whipsnakes (Colubridae: Masticophis).
- Author
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O'Connell KA and Smith EN
- Subjects
- Animals, Bayes Theorem, Biodiversity, Cell Nucleus genetics, Cytochromes c genetics, Geography, Mitochondria genetics, Species Specificity, Colubridae classification, Phylogeny
- Abstract
A stable alpha taxonomy is essential to understanding evolutionary processes and achieving effective conservation aims. Taxonomy depends on the identification of independently evolving lineages, and the delimitation of these lineages based on multiple lines of evidence. Coalescent species delimitation within an integrative framework has increased the rigor of the delimitation process. Here we use genome-wide SNP data and coalescent species delimitation to explore lineage relationships within several North American whipsnake species, test the species status of several lineages, and test the effect of missing data on species delimitation. We find support for the elevation of several previously recognized subspecies to full species status, and formally elevate two species. This study demonstrates the power of molecular data and model-based delimitation methods to identify evolutionary relationships, and finds that missing data have little impact on the outcome of delimitation analyses., (Copyright © 2018 Elsevier Inc. All rights reserved.)
- Published
- 2018
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26. Emotion theories and adolescent well-being: Results of an online intervention.
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Smith EN, Romero C, Donovan B, Herter R, Paunesku D, Cohen GL, Dweck CS, and Gross JJ
- Subjects
- Adolescent, Female, Humans, Male, Models, Psychological, Racial Groups, Child Welfare, Emotions, Internet, Psychology, Adolescent, Schools, Students psychology
- Abstract
Individuals' theories about emotions-the beliefs about the nature of emotions and the ability to influence them-have been linked to well-being. However, their causal role is not clear. To address this issue, we delivered a randomized controlled intervention to 1,645 middle school students that targeted their theories of emotion through interactive online modules. Students were taught that they could modify their emotions, get better at modifying their emotions with practice, and use strategies to improve their well-being. One month later, we found that students assigned to the intervention condition (compared to an active control condition) reported more adaptive theories of emotion and greater emotional well-being in school, although well-being outside of school was unchanged. Secondary analyses showed that these effects were present regardless of students' race, gender, or grade level. These findings suggest that theories of emotion may be a promising target for improving adolescent well-being. (PsycINFO Database Record, ((c) 2018 APA, all rights reserved).)
- Published
- 2018
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27. A New Megophrys Kuhl and Van Hasselt (Amphibia: Megophryidae) from southwestern Sumatra, Indonesia.
- Author
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Munir M, Hamidy A, Farajallah A, and Smith EN
- Subjects
- Animals, Borneo, Indonesia, Male, Philippines, Phylogeny, Amphibians
- Abstract
Megophrys lancip sp. nov., from the Bukit Barisan mountain range of southwestern Sumatra, Indonesia, is described on the basis of molecular and morphological evidence. The new species is distinguished from its congeners in Sumatra, Java, Borneo, and the Philippines by having a medium-sized body, snout with an extremely pointed rostral appendage, a medium-sized triangular eyelid appendage, a dorsolateral fold extending from just behind the eye to the groin, vomerine teeth, vocal slits, nuptial pads on the dorsomedial surface of the first and second fingers in males, and in lacking a Y, X, or H-shaped fold on the dorsum. Morphologically, the new species is most similar to M. montana, but it has a longer rostral appendage, shorter eyelid appendages, and less developed toe webbing. We also evaluate the taxonomic status of M. parallela and comment on the occurrence of M. aceras in Sumatra.
- Published
- 2018
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28. Synchronous diversification of parachuting frogs (Genus Rhacophorus) on Sumatra and Java.
- Author
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O'Connell KA, Hamidy A, Kurniawan N, Smith EN, and Fujita MK
- Subjects
- Animals, Anura genetics, Bayes Theorem, Biodiversity, Cluster Analysis, DNA, Mitochondrial genetics, Gene Flow, Genetic Variation, Indonesia, Likelihood Functions, Phylogeography, Polymorphism, Single Nucleotide genetics, Species Specificity, Anura classification, Islands, Phylogeny
- Abstract
Geological and climatological processes can drive the synchronous diversification of co-distributed species. The islands of Sumatra and Java have experienced complex geological and climatological histories, including extensive sea-level changes and the formation of valleys between northern, central, and southern components of the Barisan Mountain Range, which may have promoted diversification of their resident species. We investigate diversification on these islands using 13 species of the parachuting frog genus Rhacophorus. We use both mitochondrial and nuclear sequence data, along with genome-wide SNPs to estimate phylogenetic structure and divergence times, and to test for synchronous diversification. We find support for synchronous divergence among sister-species pairs from Sumatra and Java ∼9 Ma, as well as of populations of four co-distributed taxa on Sumatra ∼5.6 Ma. We found that sister species diverged in allopatry on Sumatra and conclude that divergence on Sumatra and Java was affected by sea-level fluctuations that promoted isolation in allopatry., (Copyright © 2018 Elsevier Inc. All rights reserved.)
- Published
- 2018
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29. Systematics of the frogs allocated to Sarcohyla bistincta sensu lato (Cope, 1877), with description of a new species from Western Mexico.
- Author
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Campbell JA, Brodie EDJ, Caviedes-Solis IW, De Oca AN, Luja VH, Flores-Villela O, GarcÍa-vÁzquez UO, Sarker GC, Wostl E, and Smith EN
- Subjects
- Animals, Mexico, Anura
- Abstract
A new species of hylid frog is described from the southwestern edge of the Mexican Plateau from the states of Morelos and Mexico through Michoacán and Jalisco, reaching the Sierra Madre Occidental in Sinaloa and western Durango. The new species is part of the widespread Mexican hylid Sarcohyla bistincta (sensu amplo) complex, comprised of S. bistincta, S. pentheter, S. calthula, and S. ephemera. One subspecies of S. bistincta (labeculata) was proposed for an isolated population in Oaxaca. We restrict the group's nominal species, S. bistincta (sensu stricto), to the Sierra Madre Oriental of Mexico and southward into the Sierra Madre del Sur of Guerrero and Oaxaca. Examination of type material places S. calthula and S. ephemera in the synonymy of S. labeculata (new combination). The species allied to S. bistincta, namely, S. bistincta, S. labeculata, S. pentheter, and the new species described herein, are diagnosed and described following recent suggested taxonomic changes and new available material.
- Published
- 2018
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30. New molecular sequence data and species trees for North American whipsnakes.
- Author
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O'Connell KA and Smith EN
- Abstract
In this data article we present species trees based on coalescent species delimitation results for North American whipsnakes, as well as metadata pertaining to the article "The effect of missing data on coalescent species delimitation and a taxonomic revision of whipsnakes (Colubridae: Masticophis)" (MPE-2017-76-R1). Species trees were constructed using SNP data generated from double-digest RADseq, filtered to 80% completeness between species. Tables correspond with the primary manuscript and serve as a repository of genetic sequence information for whipsnakes. These data can be downloaded and combined with future whipsnake datasets.
- Published
- 2018
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31. Geographical features are the predominant driver of molecular diversification in widely distributed North American whipsnakes.
- Author
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O'Connell KA, Streicher JW, Smith EN, and Fujita MK
- Subjects
- Animals, Central America, DNA, Mitochondrial genetics, Gene Flow, Geography, North America, Phylogeny, Polymorphism, Single Nucleotide, Biological Evolution, Colubridae classification, Genetics, Population
- Abstract
Allopatric divergence following the formation of geographical features has been implicated as a major driver of evolutionary diversification. Widespread species complexes provide opportunities to examine allopatric divergence across varying degrees of isolation in both time and space. In North America, several geographical features may play such a role in diversification, including the Mississippi River, Pecos River, Rocky Mountains, Cochise Filter Barrier, Gulf of California and Isthmus of Tehuantepec. We used thousands of nuclear single nucleotide polymorphisms (SNPs) and mitochondrial DNA from several species of whipsnakes (genera Masticophis and Coluber) distributed across North and Central America to investigate the role that these geographical features have played on lineage divergence. We hypothesize that these features restrict gene flow and separate whipsnakes into diagnosable genomic clusters. We performed genomic clustering and phylogenetic reconstructions at the species and population levels using Bayesian and likelihood analyses and quantified migration levels across geographical features to assess the degree of genetic isolation due to allopatry. Our analyses suggest that (i) major genetic divisions are often consistent with isolation by geographical features, (ii) migration rates between clusters are asymmetrical across major geographical features, and (iii) areas that receive proportionally more migrants possess higher levels of genetic diversity. Collectively, our findings suggest that multiple features of the North American landscape contributed to allopatric divergence in this widely distributed snake group., (© 2017 John Wiley & Sons Ltd.)
- Published
- 2017
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32. Would behavioral thermoregulation enable pregnant viviparous tropical lizards to cope with a warmer world?
- Author
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López-Alcaide S, Nakamura M, Smith EN, and Martínez-Meyer E
- Subjects
- Animals, Behavior, Animal, Female, Temperature, Body Temperature Regulation, Lizards
- Abstract
Sceloporus lizards depend on external heat to achieve their preferred temperature (T
sel ) for performing physiological processes. Evidence both in the field and laboratory indicates that pregnant females of this Genus select body temperatures (Tb ) lower than 34 °C as higher temperatures may be lethal to embryos. Therefore, thermoregulation is crucial for successful embryo development. Given the increase in global air temperature, it is expected that the first compensatory response of species that inhabit tropical climates will be behavioral thermoregulation. We tested whether viviparous Sceloporus formosus group lizards in the wild exhibited differences in thermoregulatory behavior to achieve the known Tsel for developing embryos regardless of local thermal conditions. We quantified field active body temperature, thermoregulatory behavior mechanisms (time of sighting, microhabitat used and basking time) and available microhabitat thermal conditions (i.e. operative temperature) for 10 lizard species during gestation, distributed along an altitudinal gradient. We applied both conventional and phylogenic analyses to explore whether Tb or behavioral thermoregulation could be regulated in response to different thermal conditions. These species showed no significant differences in field Tb during gestation regardless of local thermal conditions. In contrast, they exhibited significant differences in their behavioral thermoregulation associated with local environmental conditions. Based on these observations, the differences in thermoregulatory behavior identified are interpreted as compensatory adjustments to local thermal conditions. We conclude that these species may deal with higher temperatures predicted for the tropics by modulating their thermoregulatory behavior., (© 2017 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.)- Published
- 2017
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33. A new species of Pseudocalotes (Squamata: Agamidae) from the Bukit Barisan Range of Sumatra with an Estimation of its phylogeny.
- Author
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Harvey MB, Shaney K, Hamidy A, Kurniawan N, and Smith EN
- Subjects
- Animal Distribution, Animal Structures, Animals, Body Size, Indonesia, Organ Size, Phylogeny, Lizards
- Abstract
We describe a new species of Pseudocalotes from montane forests of the central, western coast of Sumatra. The combination of 3 or 4 interoculabials, slightly enlarged and heavily keeled scales on the lower flanks, a white scapular spot, a relatively long fifth toe, bicarinate lamellae at the base of Toe III, absence of a postrictal modified scale, and three rows of paravertebrals directed dorsally and posteriorly distinguishes the new species from its congeners on Sumatra and Java. Among the new characters defined in this study, counts of subdigital lamellae within the "span of Toe V" proved particularly useful for diagnosing species of Pseudocalotes. Phylogenetic analysis of DNA sequences identified a monophyletic group containing the Sumatran and Javan Pseudocalotes. Based on the phylogeny, we define a P. cybelidermus Group containing P. cybelidermus and P. guttalineatus and a P. tympanistriga Group containing P. tympanistriga, P. rhammanotus, and the new species. Combinations of five morphological characters define each of these two clades. As currently defined, Pseudocalotes is polyphyletic; Javan and Sumatran species are more closely related to other draconines such as Dendragama boulengeri than they are to some mainland species.
- Published
- 2017
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34. Phylogeographic and population genetic analyses reveal multiple species of Boa and independent origins of insular dwarfism.
- Author
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Card DC, Schield DR, Adams RH, Corbin AB, Perry BW, Andrew AL, Pasquesi GI, Smith EN, Jezkova T, Boback SM, Booth W, and Castoe TA
- Subjects
- Animals, Bayes Theorem, Biological Evolution, Boidae classification, Boidae physiology, DNA chemistry, DNA isolation & purification, DNA metabolism, DNA, Mitochondrial chemistry, DNA, Mitochondrial genetics, DNA, Mitochondrial metabolism, Dwarfism pathology, Dwarfism veterinary, Gene Frequency, Genetic Variation, Haplotypes, Mitochondria genetics, Mitochondria metabolism, Phylogeny, Phylogeography, Polymorphism, Single Nucleotide, Sequence Analysis, DNA, Boidae genetics, Genetics, Population
- Abstract
Boa is a Neotropical genus of snakes historically recognized as monotypic despite its expansive distribution. The distinct morphological traits and color patterns exhibited by these snakes, together with the wide diversity of ecosystems they inhabit, collectively suggest that the genus may represent multiple species. Morphological variation within Boa also includes instances of dwarfism observed in multiple offshore island populations. Despite this substantial diversity, the systematics of the genus Boa has received little attention until very recently. In this study we examined the genetic structure and phylogenetic relationships of Boa populations using mitochondrial sequences and genome-wide SNP data obtained from RADseq. We analyzed these data at multiple geographic scales using a combination of phylogenetic inference (including coalescent-based species delimitation) and population genetic analyses. We identified extensive population structure across the range of the genus Boa and multiple lines of evidence for three widely-distributed clades roughly corresponding with the three primary land masses of the Western Hemisphere. We also find both mitochondrial and nuclear support for independent origins and parallel evolution of dwarfism on offshore island clusters in Belize and Cayos Cochinos Menor, Honduras., (Copyright © 2016 Elsevier Inc. All rights reserved.)
- Published
- 2016
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35. Genetic surfing, not allopatric divergence, explains spatial sorting of mitochondrial haplotypes in venomous coralsnakes.
- Author
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Streicher JW, McEntee JP, Drzich LC, Card DC, Schield DR, Smart U, Parkinson CL, Jezkova T, Smith EN, and Castoe TA
- Subjects
- Animals, Evolution, Molecular, Mexico, Phylogeny, United States, DNA, Mitochondrial genetics, Elapidae genetics, Gene Flow, Haplotypes
- Abstract
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 study designed to delimit species within a clade of venomous coralsnakes, we identified an unusual pattern within the Texas coral snake (Micrurus tener): strong spatial sorting of divergent mitochondrial (mtDNA) lineages over a portion of its range, but weak sorting of these lineages elsewhere. We tested three alternative hypotheses to explain this pattern-local adaptation, secondary contact following allopatric divergence, and range expansion. Collectively, near panmixia of nuclear DNA, the signal of range expansion associated sampling drift, expansion origins in the Gulf Coast of Mexico, and species distribution modeling suggest that the spatial sorting of divergent mtDNA lineages within M. tener has resulted from genetic surfing of standing mtDNA variation-not local adaptation or allopatric divergence. Our findings highlight the potential for the stochastic effects of recent range expansion to mislead estimations of population divergence made from mtDNA, which may be exacerbated in systems with low vagility, ancestral mtDNA polymorphism, and male-biased dispersal., (© 2016 The Author(s).)
- Published
- 2016
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36. Redescription Cyrtodactylus lateralis (Werner) (Squamata: Gekkonidae) and Phylogeny of the Prehensile-tailed Cyrtodactylus.
- Author
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Harvey MB, O'connell KA, Wostl E, Riyanto A, Kurniawan N, Smith EN, and Grismer LL
- Subjects
- Animal Distribution, Animals, Female, Indonesia, Lizards genetics, Lizards physiology, Male, Species Specificity, Lizards anatomy & histology, Lizards classification, Phylogeny
- Abstract
We redescribe Cyrtodactylus lateralis (Werner) on the basis of new specimens. Cyrtodactylus lateralis is a prehensile-tailed species, known from scattered lowland to mid-elevation localities in northern Sumatra. The prehensile-tailed Cyrtodactylus are more speciose and have a wider distribution than previously thought. This group includes a mainland SE Asian clade consisting of C. elok, C. interdigitalis, and C. brevipalmatus and an insular clade containing C. durio, C. lateralis, C. nuaulu, C. serratus, C. spinosus, and C. stresemanni. However, a distinctive color pattern in the Wallacean and Papuan species and uncertainty surrounding the type locality of C. stresemanni raise unresolved questions about the inclusiveness of the insular clade. DNA sequence data supports a close relationship between C. elok and C. interdigitalis, but also reveals that C. lateralis and C. durio are not closely related to these species.
- Published
- 2016
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37. Two new species of Cyrtodactylus (Squamata: Gekkonidae) from the Southern Bukit Barisan Range of Sumatra and an estimation of their phylogeny.
- Author
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Harvey MB, O'connell KA, Barraza G, Riyanto A, Kurniawan N, and Smith EN
- Subjects
- Animals, Female, Indonesia, Male, Phylogeny, Lizards anatomy & histology, Lizards classification
- Abstract
We describe Cyrtodactylus psarops sp. nov. and C. semicinctus sp. nov., two new species of bent-toed geckos from montane forests in the southern Bukit Barisan Range of Sumatra, Indonesia. The new species are closely related to one another and to C. semenanjungensis, a lowland species currently known only from Peninsular Malaysia. Three characters of the new species immediately distinguish them from most congeners in the Sunda Region: they lack transversely enlarged subcaudals, have a precloacal depression, and have a greatly enlarged scale positioned at the apex of a continuous series of femoral and precloacal pore-bearing scales. They differ from one another in cephalic pattern, tuberculation of the brachium, and in numbers of cloacal tubercles, dorsal bands, and ventrals in a transverse row. The greatly enlarged scale at the apex of the precloacal pores appears to be a rare apomorphy of these two species and C. agamensis.
- Published
- 2015
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38. Correction: Rapid Microsatellite Identification from Illumina Paired-End Genomic Sequencing in Two Birds and a Snake.
- Author
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Castoe TA, Poole AW, de Koning AP, Jones KL, Tomback DF, Oyler-McCance SJ, Fike JA, Lance SL, Streicher JW, Smith EN, and Pollock DD
- Published
- 2015
- Full Text
- View/download PDF
39. Mind-set interventions are a scalable treatment for academic underachievement.
- Author
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Paunesku D, Walton GM, Romero C, Smith EN, Yeager DS, and Dweck CS
- Subjects
- Adolescent, Female, Humans, Male, Schools, Self Concept, Students, Achievement, Adolescent Development, Attitude, Educational Measurement, Underachievement
- Abstract
The efficacy of academic-mind-set interventions has been demonstrated by small-scale, proof-of-concept interventions, generally delivered in person in one school at a time. Whether this approach could be a practical way to raise school achievement on a large scale remains unknown. We therefore delivered brief growth-mind-set and sense-of-purpose interventions through online modules to 1,594 students in 13 geographically diverse high schools. Both interventions were intended to help students persist when they experienced academic difficulty; thus, both were predicted to be most beneficial for poorly performing students. This was the case. Among students at risk of dropping out of high school (one third of the sample), each intervention raised students' semester grade point averages in core academic courses and increased the rate at which students performed satisfactorily in core courses by 6.4 percentage points. We discuss implications for the pipeline from theory to practice and for education reform., (© The Author(s) 2015.)
- Published
- 2015
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40. Estimating the temporal and spatial extent of gene flow among sympatric lizard populations (genus Sceloporus) in the southern Mexican highlands.
- Author
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Grummer JA, Calderón-Espinosa ML, Nieto-Montes de Oca A, Smith EN, Méndez-de la Cruz FR, and Leaché AD
- Subjects
- Animals, Bayes Theorem, Cell Nucleus genetics, DNA, Mitochondrial genetics, Likelihood Functions, Mexico, Models, Genetic, Models, Statistical, Molecular Sequence Data, Phylogeography, Sequence Analysis, DNA, Gene Flow, Genetics, Population, Lizards genetics, Phylogeny, Sympatry
- Abstract
Interspecific gene flow is pervasive throughout the tree of life. Although detecting gene flow between populations has been facilitated by new analytical approaches, determining the timing and geography of hybridization has remained difficult, particularly for historical gene flow. A geographically explicit phylogenetic approach is needed to determine the overlap of ancestral populations. In this study, we performed population genetic analyses, species delimitation, simulations and a recently developed approach of species tree diffusion to infer the phylogeographic history, timing and geographic extent of gene flow in lizards of the Sceloporus spinosus group. The two species in this group, S. spinosus and S. horridus, are distributed in eastern and western portions of Mexico, respectively, but populations of these species are sympatric in the southern Mexican highlands. We generated data consisting of three mitochondrial genes and eight nuclear loci for 148 and 68 individuals, respectively. We delimited six lineages in this group, but found strong evidence of mito-nuclear discordance in sympatric populations of S. spinosus and S. horridus owing to mitochondrial introgression. We used coalescent simulations to differentiate ancestral gene flow from secondary contact, but found mixed support for these two models. Bayesian phylogeography indicated more than 60% range overlap between ancestral S. spinosus and S. horridus populations since the time of their divergence. Isolation-migration analyses, however, revealed near-zero levels of gene flow between these ancestral populations. Interpreting results from both simulations and empirical data indicate that despite a long history of sympatry among these two species, gene flow in this group has only recently occurred., (© 2015 John Wiley & Sons Ltd.)
- Published
- 2015
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41. Three new species of Pseudocalotes (Squamata: Agamidae) from southern Sumatra, Indonesia.
- Author
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Harvey MB, Hamidy A, Kurniawan N, Shaney K, and Smith EN
- Subjects
- Animal Distribution, Animal Structures anatomy & histology, Animal Structures growth & development, Animals, Body Size, Ecosystem, Female, Indonesia, Lizards anatomy & histology, Lizards growth & development, Male, Organ Size, Lizards classification
- Abstract
We describe three new species of Pseudocalotes from the Bukit Barisan Range of southern Sumatra, Indonesia. Pseudocalotes cybelidermus, P. guttalineatus, and P. rhammanotus differ from most congeners in having serrate dorsal crests that extend to the base of the tail and a dorsolateral series of enlarged heavily keeled scales. In these new species, subdigital lamellae of Toe III have prominent preaxial keels and lack or have greatly reduced postaxial keels. In contrast, P. rhammanotus resembles P. tympanistriga by having bicarinate subdigital lamellae at the base of Toe III. Like most congeners, these new species appear to be restricted to humid forests above 1000 m. We report several new morphological characters for Pseudocalotes and discuss their diagnostic value. Future systematic studies of this genus should assess presence/absence of interparietals, four different kinds of modified scales on the neck, a dorsolateral series of heavily keeled scales, and unicarinate lamellae under the distal phalanges of most fingers and toes. Our comparisons among congeners demonstrate the diagnostic value of width of the gap between the nuchal and dorsal crests and frequency data for contact between the nasal and supralabials and between the postmentals and infralabials. Finally, we discuss variation in morphology of subdigital lamellae at the base of Toe III and describe new conditions intermediate between the serrate fringe of most Indochinese species and the bicarinate lamellae of the P. tympanistriga.
- Published
- 2014
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42. The Burmese python genome reveals the molecular basis for extreme adaptation in snakes.
- Author
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Castoe TA, de Koning AP, Hall KT, Card DC, Schield DR, Fujita MK, Ruggiero RP, Degner JF, Daza JM, Gu W, Reyes-Velasco J, Shaney KJ, Castoe JM, Fox SE, Poole AW, Polanco D, Dobry J, Vandewege MW, Li Q, Schott RK, Kapusta A, Minx P, Feschotte C, Uetz P, Ray DA, Hoffmann FG, Bogden R, Smith EN, Chang BS, Vonk FJ, Casewell NR, Henkel CV, Richardson MK, Mackessy SP, Bronikowski AM, Yandell M, Warren WC, Secor SM, and Pollock DD
- Subjects
- Animals, Cell Cycle physiology, Humans, Organ Specificity physiology, Adaptation, Physiological physiology, Boidae genetics, Boidae metabolism, Evolution, Molecular, Gene Expression Regulation physiology, Genome physiology, Transcription, Genetic physiology
- Abstract
Snakes possess many extreme morphological and physiological adaptations. Identification of the molecular basis of these traits can provide novel understanding for vertebrate biology and medicine. Here, we study snake biology using the genome sequence of the Burmese python (Python molurus bivittatus), a model of extreme physiological and metabolic adaptation. We compare the python and king cobra genomes along with genomic samples from other snakes and perform transcriptome analysis to gain insights into the extreme phenotypes of the python. We discovered rapid and massive transcriptional responses in multiple organ systems that occur on feeding and coordinate major changes in organ size and function. Intriguingly, the homologs of these genes in humans are associated with metabolism, development, and pathology. We also found that many snake metabolic genes have undergone positive selection, which together with the rapid evolution of mitochondrial proteins, provides evidence for extensive adaptive redesign of snake metabolic pathways. Additional evidence for molecular adaptation and gene family expansions and contractions is associated with major physiological and phenotypic adaptations in snakes; genes involved are related to cell cycle, development, lungs, eyes, heart, intestine, and skeletal structure, including GRB2-associated binding protein 1, SSH, WNT16, and bone morphogenetic protein 7. Finally, changes in repetitive DNA content, guanine-cytosine isochore structure, and nucleotide substitution rates indicate major shifts in the structure and evolution of snake genomes compared with other amniotes. Phenotypic and physiological novelty in snakes seems to be driven by system-wide coordination of protein adaptation, gene expression, and changes in the structure of the genome.
- Published
- 2013
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43. Phylogenetic relationships of the enigmatic longtailed rattlesnakes (Crotalus ericsmithi, C. lannomi, and C. stejnegeri).
- Author
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Reyes-Velasco J, Meik JM, Smith EN, and Castoe TA
- Subjects
- Animals, Bayes Theorem, Cell Nucleus genetics, Crotalus genetics, DNA, Mitochondrial genetics, Likelihood Functions, Mexico, Models, Genetic, Phylogeography, Sequence Analysis, DNA, Biological Evolution, Crotalus classification, Phylogeny
- Abstract
The longtailed rattlesnakes of western Mexico represent an enigmatic group of poorly known venomous snake species: Crotalus ericsmithi, C. lannomi, and C. stejnegeri. In the 120 years since their discovery, fewer than twenty individuals have been deposited in natural history collections worldwide. These three species share similar morphological traits, including a particularly long tail that has been interpreted as either an ancestral condition among rattlesnakes or as derived within the longtailed group. An understanding of the phylogenetic distinctiveness and relationships among the longtailed rattlesnakes, and their relationships to other rattlesnake groups, has previously been hampered by a dearth of comparative material and tissues for collection of DNA sequence data. Facilitated by the recent availability of tissue samples from multiple individuals of each species, we estimate the phylogenetic relationships among the longtailed rattlesnakes and their placement among other rattlesnake groups, using DNA sequence data from three mitochondrial and three nuclear gene fragments. We explore phylogenetic signal in our data using Bayesian and maximum likelihood methods, species tree analyses and hypothesis testing. Our results strongly support the monophyly of longtailed rattlesnakes and suggest the three species diverged from each other during the mid to late Pliocene or early Pleistocene (~1.5-5.6 mya). Contrary to prevailing hypotheses, we find no evidence for an early or basal divergence of the longtailed clade within the rattlesnake tree, and instead estimate that it diverged relatively recently (~6.8 mya) from its sister lineage, composed of the diamondback rattlesnakes (C. atrox group) and the prairie rattlesnakes (C. viridis group). With our added sampling of lineages and identification of previously used problematic sequences, we provide a revised hypothesis for relationships among Crotalus species, yet underscore the need for future studies and new data to deliver a well-supported robust estimate of rattlesnake relationships., (Copyright © 2013 Elsevier Inc. All rights reserved.)
- Published
- 2013
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44. Isolation, characterization, cloning and expression of an alpha-neurotoxin from the venom of the Mexican coral snake Micrurus laticollaris (Squamata: Elapidae).
- Author
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Carbajal-Saucedo A, López-Vera E, Bénard-Valle M, Smith EN, Zamudio F, de Roodt AR, and Olvera-Rodríguez A
- Subjects
- Amino Acid Sequence, Animals, Chemical Fractionation, Chromatography, High Pressure Liquid, Cloning, Molecular, Elapid Venoms chemistry, Elapid Venoms isolation & purification, Elapid Venoms metabolism, Elapid Venoms toxicity, Female, Mice, Molecular Sequence Data, Oocytes drug effects, Oocytes physiology, Patch-Clamp Techniques, Rabbits, Receptors, Nicotinic metabolism, Recombinant Fusion Proteins, Spectrometry, Mass, Electrospray Ionization, Xenopus laevis, Elapid Venoms genetics, Elapidae physiology, Receptors, Nicotinic drug effects
- Abstract
A new member of short chain α-neurotoxic protein family from venom of the Mexican coral snake, Micrurus laticollaris, was characterized. This protein, named MlatA1, possesses 61 amino acids with 8 conserved cysteine residues, sharing 30-91% sequence identity with other fully sequenced Micrurus toxins. MlatA1 (LD50i.v. = 0.064 mg/kg) antagonizes with both fetal and adult nicotinic acetylcholine receptor (nAChR) as well as α-7 neuronal nAChR in a dose-dependent way. Specific rabbit anti-Mlat serum (titer higher than 18,000) does not show any protective ability against this toxin, nevertheless it was able to recognize protein bands in six out of twelve Micrurus venoms showing the existence of two distinct antigenic groups for α-neurotoxins in North American coral snakes species. The MlatA1 gene was cloned and used to produce recombinant toxin (rMlatA1) that was recognized by rabbit anti-native toxin but was depleted of toxic activity., (Copyright © 2013. Published by Elsevier Ltd.)
- Published
- 2013
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45. Thousands of microsatellite loci from the venomous coralsnake Micrurus fulvius and variability of select loci across populations and related species.
- Author
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Castoe TA, Streicher JW, Meik JM, Ingrasci MJ, Poole AW, de Koning AP, Campbell JA, Parkinson CL, Smith EN, and Pollock DD
- Subjects
- Animals, Mexico, Molecular Sequence Data, Sequence Analysis, DNA, United States, Biota, Elapidae classification, Elapidae genetics, Genetic Variation, Microsatellite Repeats
- Abstract
Studies of population genetics increasingly use next-generation DNA sequencing to identify microsatellite loci in nonmodel organisms. There are, however, relatively few studies that validate the feasibility of transitioning from marker development to experimental application across populations and species. North American coralsnakes of the Micrurus fulvius species complex occur in the United States and Mexico, and little is known about their population structure and phylogenetic relationships. This absence of information and population genetics markers is particularly concerning because they are highly venomous and have important implications on human health. To alleviate this problem in coralsnakes, we investigated the feasibility of using 454 shotgun sequences for microsatellite marker development. First, a genomic shotgun library from a single individual was sequenced (approximately 7.74 megabases; 26,831 reads) to identify potentially amplifiable microsatellite loci (PALs). We then hierarchically sampled 76 individuals from throughout the geographic distribution of the species complex and examined whether PALs were amplifiable and polymorphic. Approximately half of the loci tested were readily amplifiable from all individuals, and 80% of the loci tested for variation were variable and thus informative as population genetic markers. To evaluate the repetitive landscape characteristics across multiple snakes, we also compared microsatellite content between the coralsnake and two other previously sampled snakes, the venomous copperhead (Agkistrodon contortrix) and Burmese python (Python molurus)., (© 2012 Blackwell Publishing Ltd.)
- Published
- 2012
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46. Rapid range expansion in the Great Plains narrow-mouthed toad (Gastrophryne olivacea) and a revised taxonomy for North American microhylids.
- Author
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Streicher JW, Cox CL, Campbell JA, Smith EN, and de Sá RO
- Subjects
- Animals, Anura genetics, Bayes Theorem, Cell Nucleus genetics, DNA, Mitochondrial genetics, Fossils, Geography, Haplotypes, Likelihood Functions, Mexico, Sequence Analysis, DNA, United States, Anura classification, Genetic Variation, Genetics, Population, Phylogeny
- Abstract
We investigated genetic variation within the Great Plains narrow-mouthed toad, Gastrophryne olivacea, across its geographic range in the United States and Mexico. An analysis of mitochondrial DNA (mtDNA) from 105 frogs revealed remarkably low levels of genetic diversity in individuals inhabiting the central United States and northern Mexico. We found that this widespread matrilineal lineage is divergent (ca. 2% in mtDNA) from haplotypes that originate from the western United States and western coast of Mexico. Using a dataset that included all five species of Gastrophryne and both species of the closely related genus Hypopachus, we investigated the phylogenetic placement of G. olivacea. This analysis recovered strong support that G. olivacea, the tropically distributed G. elegans, and the temperately distributed G. carolinensis constitute a monophyletic assemblage. However, the placement of G. pictiventris and G. usta render Gastrophryne paraphyletic with respect to Hypopachus. To complement our mitochondrial analysis, we examined a small fragment of nuclear DNA and recovered consistent patterns. In light of our findings we recommend (1) the resurrection of the nomen G. mazatlanensisTaylor (1943) for the disjunct western clade of G. olivacea and (2) the tentative placement of G. pictiventris and G. usta in Hypopachus. To explore possible scenarios leading to low levels of genetic diversity in G. olivacea, we used mismatch distributions and Bayesian Skyline plots to examine historic population expansion and demography. Collectively these analyses suggest that G. olivacea rapidly expanded in effective population size and geographic range during the late Pleistocene or early Holocene. This hypothesis is consistent with fossil data from northern localities and contemporary observations that suggest ongoing northern expansion. Given our findings, we suspect that the rapid range expansion of G. olivacea may have been facilitated by ecological associations with open habitats and seasonal water bodies., (Copyright © 2012 Elsevier Inc. All rights reserved.)
- Published
- 2012
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47. Rampant horizontal transfer of SPIN transposons in squamate reptiles.
- Author
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Gilbert C, Hernandez SS, Flores-Benabib J, Smith EN, and Feschotte C
- Subjects
- Animals, Genes, RAG-1 genetics, Genes, mos genetics, Molecular Sequence Data, Phylogeny, Reptiles classification, Sequence Analysis, DNA, DNA Transposable Elements genetics, Evolution, Molecular, Gene Transfer, Horizontal, Reptiles genetics
- Abstract
Transposable elements (TEs) are highly abundant in the genome and capable of mobility, two properties that make them particularly prone to transfer horizontally between organisms. Although the impact of horizontal transfer (HT) of TEs is well recognized in prokaryotes, the frequency of this phenomenon and its contribution to genome evolution in eukaryotes remain poorly appreciated. Here, we provide evidence that a DNA transposon called SPIN has colonized the genome of 17 species of reptiles representing nearly every major lineage of squamates, including 14 families of lizards, snakes, and amphisbaenians. Slot blot analyses indicate that SPIN has amplified to high copy numbers in most of these species, ranging from 2,000-28,000 copies per haploid genome. In contrast, we could not detect the presence of SPIN in any of the turtles (seven species from seven families) and crocodiles (four species) examined. Genetic distances between SPIN sequences from species belonging to different squamate families are consistently very low (average = 0.1), considering the deep evolutionary divergence of the families investigated (most are >100 My diverged). Furthermore, these distances fall below interfamilial distances calculated for two genes known to have evolved under strong functional constraint in vertebrates (RAG1, average = 0.24 and C-mos, average = 0.27). These data, combined with phylogenetic analyses, indicate that the widespread distribution of SPIN among squamates is the result of at least 13 independent events of HTs. Molecular dating and paleobiogeographical data suggest that these transfers took place during the last 50 My on at least three different continents (North America, South America and, Africa). Together, these results triple the number of known SPIN transfer events among tetrapods, provide evidence for a previously hypothesized transoceanic movement of SPIN transposons during the Cenozoic, and further underscore the role of HT in the evolution of vertebrate genomes.
- Published
- 2012
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48. Rapid microsatellite identification from Illumina paired-end genomic sequencing in two birds and a snake.
- Author
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Castoe TA, Poole AW, de Koning AP, Jones KL, Tomback DF, Oyler-McCance SJ, Fike JA, Lance SL, Streicher JW, Smith EN, and Pollock DD
- Subjects
- Animals, Birds, Genome, Genomics economics, High-Throughput Nucleotide Sequencing economics, Repetitive Sequences, Nucleic Acid, Snakes, Genomics methods, High-Throughput Nucleotide Sequencing methods, Microsatellite Repeats genetics
- Abstract
Identification of microsatellites, or simple sequence repeats (SSRs), can be a time-consuming and costly investment requiring enrichment, cloning, and sequencing of candidate loci. Recently, however, high throughput sequencing (with or without prior enrichment for specific SSR loci) has been utilized to identify SSR loci. The direct "Seq-to-SSR" approach has an advantage over enrichment-based strategies in that it does not require a priori selection of particular motifs, or prior knowledge of genomic SSR content. It has been more expensive per SSR locus recovered, however, particularly for genomes with few SSR loci, such as bird genomes. The longer but relatively more expensive 454 reads have been preferred over less expensive Illumina reads. Here, we use Illumina paired-end sequence data to identify potentially amplifiable SSR loci (PALs) from a snake (the Burmese python, Python molurus bivittatus), and directly compare these results to those from 454 data. We also compare the python results to results from Illumina sequencing of two bird genomes (Gunnison Sage-grouse, Centrocercus minimus, and Clark's Nutcracker, Nucifraga columbiana), which have considerably fewer SSRs than the python. We show that direct Illumina Seq-to-SSR can identify and characterize thousands of potentially amplifiable SSR loci for as little as $10 per sample--a fraction of the cost of 454 sequencing. Given that Illumina Seq-to-SSR is effective, inexpensive, and reliable even for species such as birds that have few SSR loci, it seems that there are now few situations for which prior hybridization is justifiable.
- Published
- 2012
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49. Neuromuscular activity of the venoms of the Colombian coral snakes Micrurus dissoleucus and Micrurus mipartitus: an evolutionary perspective.
- Author
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Renjifo C, Smith EN, Hodgson WC, Renjifo JM, Sanchez A, Acosta R, Maldonado JH, and Riveros A
- Subjects
- Animals, Chickens, Elapid Venoms chemistry, In Vitro Techniques, Muscle Contraction drug effects, Neostigmine pharmacology, Phospholipase A2 Inhibitors, Phylogeny, Elapid Venoms pharmacology, Elapidae, Neuromuscular Junction drug effects
- Abstract
The venoms of coral snakes (genus Micrurus) are known to induce a broad spectrum of pharmacological activities. While some studies have investigated their potential human effects, little is known about their mechanism of action in terms of the ecological diversity and evolutionary relationships among the group. In the current study we investigated the neuromuscular blockade of the venom of two sister species Micrurus mipartitus and Micrurus dissoleucus, which exhibit divergent ecological characteristics in Colombia, by using the chick biventer cervicis nerve-muscle preparation. We also undertook a phylogenetic analysis of these species and their congeners, in order to provide an evolutionary framework for the American coral snakes. The venom of M. mipartitus caused a concentration-dependant inhibition (3-10 μg/ml) of nerve-mediated twitches and significantly inhibited contractile responses to exogenous ACh (1 mM), but not KCl (40 mM), indicating a postsynaptic mechanism of action. The inhibition of indirect twitches at the lower venom dose (3 μg/ml) showed to be triphasic and the effect was further attenuated when PLA2 was inhibited. M. dissoleucus venom (10-50 μg/ml) failed to produce a complete blockade of nerve-mediated twitches within a 3 h time period and significantly inhibited contractile responses to exogenous ACh (1 mM) and KCl (40 mM), indicating both postsynaptic and myotoxic mechanisms of action. Myotoxic activity was confirmed by morphological studies of the envenomed tissues. Our results demonstrate a hitherto unsuspected diversity of pharmacological actions in closely related species which exhibit divergent ecological characteristics; these results have important implications for both the clinical management of Coral snake envenomings and the design of Micrurus antivenom., (Copyright © 2011 Elsevier Ltd. All rights reserved.)
- Published
- 2012
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50. Molecular systematics of the Middle American genus Hypopachus (Anura: Microhylidae).
- Author
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Greenbaum E, Smith EN, and de Sá RO
- Subjects
- Animals, Bayes Theorem, Cell Nucleus genetics, DNA, Mitochondrial genetics, Genetics, Population, Geography, Haplotypes, Likelihood Functions, Mexico, RNA, Ribosomal genetics, RNA, Ribosomal, 16S genetics, Rhodopsin genetics, Sequence Analysis, DNA, Texas, Anura genetics, Evolution, Molecular, Phylogeny
- Abstract
We present the first phylogenetic study on the widespread Middle American microhylid frog genus Hypopachus. Partial sequences of mitochondrial (12S and 16S ribosomal RNA) and nuclear (rhodopsin) genes (1275 bp total) were analyzed from 43 samples of Hypopachus, three currently recognized species of Gastrophryne, and seven arthroleptid, brevicipitid and microhylid outgroup taxa. Maximum parsimony (PAUP), maximum likelihood (RAxML) and Bayesian inference (MrBayes) optimality criteria were used for phylogenetic analyses, and BEAST was used to estimate divergence dates of major clades. Population-level analyses were conducted with the programs NETWORK and Arlequin. Results confirm the placement of Hypopachus and Gastrophryne as sister taxa, but the latter genus was strongly supported as paraphyletic. The African phrynomerine genus Phrynomantis was recovered as the sister taxon to a monophyletic Chiasmocleis, rendering our well-supported clade of gastrophrynines paraphyletic. Hypopachus barberi was supported as a disjunctly distributed highland species, and we recovered a basal split in lowland populations of Hypopachus variolosus from the Pacific versant of Mexico and elsewhere in the Mesoamerican lowlands. Dating analyses from BEAST estimate speciation within the genus Hypopachus occurred in the late Miocene/early Pliocene for most clades. Previous studies have not found bioacoustic or morphological differences among these lowland clades, and our molecular data support the continued recognition of two species in the genus Hypopachus., (Copyright © 2011 Elsevier Inc. All rights reserved.)
- Published
- 2011
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