Unraveling the Phylogenetic Relationships of the Eccoptochilinae, an Enigmatic Array of Ordovician Cheirurid Trilobites

The Cheiruridae are a diverse group of trilobites and several subfamilies within the clade have been the focus of recent phylogenetic studies. This paper focuses on the relationships of one of those subfamilies, the Ordovician Eccoptochilinae. We analyze sixteen species from six genera within the traditionally defined group, using the pilekiid Anacheirurus frederici as an outgroup. To assess the monophyly of the Eccoptochilinae seven sphaerexochine species, Kawina arnoldi, Sphaerexochus arenosus, S. atacius, S. latifrons, S. mirus, S. parvus, and S. scabridus were included in the analysis as well. The results of this analysis show that the genus Eccoptochile represents a paraphyletic grade and species traditionally assigned to Parasphaerexochus and Skelipyx plot within Pseudosphaerexochus. Also, representative species of Sphaerexochinae plot within the traditionally defined Eccoptochilinae, suggesting Eccoptochilinae itself is paraphyletic. To resolve this, we propose all species of Pseudosphaerexochus be placed within Sphaerexochinae and Eccoptochilinae be restricted to a monotypic Eccoptochile clavigera.This research was supported by NSF DEB-0716162

Phylogenetic and Biogeographic Analysis of Sphaerexochine Trilobites

BACKGROUND: Sphaerexochinae is a speciose and widely distributed group of cheirurid trilobites. Their temporal range extends from the earliest Ordovician through the Silurian, and they survived the end Ordovician mass extinction event (the second largest mass extinction in Earth history). Prior to this study, the individual evolutionary relationships within the group had yet to be determined utilizing rigorous phylogenetic methods. Understanding these evolutionary relationships is important for producing a stable classification of the group, and will be useful in elucidating the effects the end Ordovician mass extinction had on the evolutionary and biogeographic history of the group. METHODOLOGY/PRINCIPAL FINDINGS: Cladistic parsimony analysis of cheirurid trilobites assigned to the subfamily Sphaerexochinae was conducted to evaluate phylogenetic patterns and produce a hypothesis of relationship for the group. This study utilized the program TNT, and the analysis included thirty-one taxa and thirty-nine characters. The results of this analysis were then used in a Lieberman-modified Brooks Parsimony Analysis to analyze biogeographic patterns during the Ordovician-Silurian. CONCLUSIONS/SIGNIFICANCE: The genus Sphaerexochus was found to be monophyletic, consisting of two smaller clades (one composed entirely of Ordovician species and another composed of Silurian and Ordovician species). By contrast, the genus Kawina was found to be paraphyletic. It is a basal grade that also contains taxa formerly assigned to Cydonocephalus. Phylogenetic patterns suggest Sphaerexochinae is a relatively distinctive trilobite clade because it appears to have been largely unaffected by the end Ordovician mass extinction. Finally, the biogeographic analysis yields two major conclusions about Sphaerexochus biogeography: Bohemia and Avalonia were close enough during the Silurian to exchange taxa; and during the Ordovician there was dispersal between Eastern Laurentia and the Yangtze block (South China) and between Eastern Laurentia and Avalonia

Gestión de calidad bajo el enfoque de atención al cliente en las Mypes del sector servicio, colegios particulares, en el distrito de Callería, año 2017

TesisLa investigación se llevó a cabo con el objetivo de determinar la Gestión de la Calidad bajo el enfoque de atención al cliente en las mypes del sector servicios, colegios particulares, en el distrito de Calleria, año 2017. Se elaboró desarrollando una metodología de investigación del tipo descriptivo – correlacional - no experimental, donde se aplicó un cuestionario estructurado de 23 interrogantes a través de la técnica de encuesta, obteniéndose como resultados: Respecto al emprendedor: el 45% está en el rango de 40 a 50 años; en su mayoría son de género masculino; de profesión profesores. Respecto a la empresa y la formalización: las mypes encuestadas se encuentran formalizadas (85%) y el 15% no culmina sus trámites por espera de resoluciones; las mypes del sector en estudio están en el mercado de 4 a 6 años (50%) y los docentes si cumplen con una formación de acuerdo a ley (70%). Respecto de la gestión de calidad: 45% utiliza un plan de negocio y 20% está por implementar; el 60% tiene definido la misión, visión y valores de su empresa. Además, si cuentan con local propio (65%) y las instalaciones está pensado en el alumnado (70%); una minoría (40%) si recurre a cursos de capacitación; el 60% no prioriza está herramienta; demostrando que el 70% si tiene diseñado protocolos referentes al servicio de atención al cliente sin ningún tipo de discriminación, recogiendo sugerencias de los clientes que se fidelizan con el servicio brindado (90%)

Appendix S4 – Run Counts of Repeated Errors

A checklist of the 100 runs counting off the number of times an error in equal weighting was repeated in 1, 2, 3, and all 4 implied weights runs

Appendix S1 - TNT files

Zip file containing all 100 matrices generated from our MK model of morphological change

Appendix S5 - Character Weights Test NEXUS files

Zip folder containing all 100 nexus files used in the character weights tests. These matrices contain the same 4 characters (Character 56-59), generated with known rates of evolution

Appendix S6 - Character Weights

Excel spreadsheet of the weights/fits generated for our four characters in all 100 matrices for four values of k (1,3,5,10)

Data from: Phylogenetic revision of the Strophomenida, a diverse and ecologically important palaeozoic brachiopod order

The order Strophomenida was an ecologically abundant and taxonomically diverse group of Palaeozoic brachiopods that originated in the earliest Ordovician and went extinct in the Carboniferous. During their long geological range, the Strophomenida survived two of the ‘Big Five’ mass extinction events, the Late Ordovician and the Late Devonian, suggesting that they are potentially informative taxa for studying the evolutionary effects of these two distinct mass extinctions, each with drastically different forcing mechanisms. However, while there have been previous phylogenetic studies on smaller groups within the Strophomenida, the phylogenetic relationships of the whole group are still largely unknown. The group has been divided into two major superfamilies, the Strophomenoidea (strophomenoids) and the Plectambonitoidea (plectambonitoids). Despite being treated as separate clades, the plectambonitoids may form a paraphyletic grade into the strophomenoids. We present a detailed higher-level parsimony-based phylogenetic analysis of the Strophomenida, consisting of 69 characters and 62 exemplar species sampled from the majority of the taxonomically defined families/subfamilies. Several species of basal chonetids (strophochonetids) were also included in this analysis, as they may be closely related to the Strophomenida and share several characters with both the plectambonitoids and strophomenoids. The phylogenetic analysis suggests the plectambonitoids, as originally defined, are paraphyletic to the monophyletic strophomenoids. The basal chonetids are reconstructed as a monophyletic group that is sister to the strophomenoids, suggesting that their proper placement might be within the Strophomenida. The topology also suggests that at least 17 of the taxonomically defined strophomenoid and plectambonitoid families are likely to be monophyletic. The Plectambonitidae and the Taffiidae as defined are paraphyletic, and the Grorudiidae and Leptostrophiidae are polyphyletic. Furthermore, subfamilies Leptodontellinae, Dicoelostrophiinae, Palaeostrophomeninae and Aegiromeninae are raised to the level of family. When analysed within this phylogenetic context, the Late Ordovician mass extinction event had little effect on the large-scale evolution of the group

Unraveling the phylogenetic relationships of the Eccoptochilinae, an enigmatic array of ordovician cheirurid trilobites.

The Cheiruridae are a diverse group of trilobites and several subfamilies within the clade have been the focus of recent phylogenetic studies. This paper focuses on the relationships of one of those subfamilies, the Ordovician Eccoptochilinae. We analyze sixteen species from six genera within the traditionally defined group, using the pilekiid Anacheirurus frederici as an outgroup. To assess the monophyly of the Eccoptochilinae seven sphaerexochine species, Kawina arnoldi, Sphaerexochus arenosus, S. atacius, S. latifrons, S. mirus, S. parvus, and S. scabridus were included in the analysis as well. The results of this analysis show that the genus Eccoptochile represents a paraphyletic grade and species traditionally assigned to Parasphaerexochus and Skelipyx plot within Pseudosphaerexochus. Also, representative species of Sphaerexochinae plot within the traditionally defined Eccoptochilinae, suggesting Eccoptochilinae itself is paraphyletic. To resolve this, we propose all species of Pseudosphaerexochus be placed within Sphaerexochinae and Eccoptochilinae be restricted to a monotypic Eccoptochile clavigera

Appendix S3 - Spreadsheet of Node Counts

Excel spreadsheet with raw counts of correct, incorrect, and unknown relationships for all runs of equal and implied weighting, as well standardized counts of implied weighting relative to equal weighting, and overall counts of the relative proportions of the data which increase or decrease error