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Aptos, CA, United States

von der Heyden S.,Stellenbosch University | Bowie R.C.K.,University of California at Berkeley | Prochazka K.,Forestry and Fisheries | Bloomer P.,University of Pretoria | And 2 more authors.
Journal of Evolutionary Biology | Year: 2011

Biogeographic boundaries are the meeting zone of broadly distributed faunas, or the actual cause of a faunal break. In the latter case, closely related sister species should be found across such a boundary. To achieve such a situation, preliminary stages are expected, where phylogeographic breaks followed by genetic cryptic speciation would be observed. Biogeographic boundaries, in the Cape Point/Cape Agulhas region of southern Africa, offer an ideal system to test such predictions. Here, we studied two intertidal clinid fish species that are endemic to southern Africa, Clinus superciliosus (n=127) and Muraenoclinus dorsalis (n=114). Using mitochondrial control region, 16S rRNA, 12S rRNA and NADH2 genes and the nuclear rhodopsin and the first intron of the S7 ribosomal protein gene, we show both phylogeographic breaks and likely cryptic speciation in each species. Pairwise Φ st results suggest population genetic structuring for both species, with higher levels for M. dorsalis (Φ st=0.34-0.93) than for C. superciliosus (Φ st=0.1-0.74). Further, we recover two and three distinct lineages within M. dorsalis and C. superciliosus, respectively. Phylogenetic topologies, concordance between nuclear and mitochondrial markers and levels of sequence divergence, which are consistent with closely related sister species pairs, suggest the presence of cryptic species. Our results therefore meet the expectation for reduced gene flow at a biogeographic barrier, which translates into significant genetic breaks and cryptic sister species. © 2011 The Authors. Journal of Evolutionary Biology © 2011 European Society For Evolutionary Biology.

Scott W.G.,University of California at Santa Cruz | Szoke A.,Lawrence Livermore National Laboratory | Blaustein J.,University of California at Santa Cruz | Blaustein J.,Cabrillo College | And 2 more authors.
Life | Year: 2014

The RNA World Hypothesis posits that the first self-replicating molecules were RNAs. RNA self-replicases are, in general, assumed to have employed nucleotide 5'-polyphosphates (or their analogues) as substrates for RNA polymerization. The mechanism by which these substrates might be synthesized with sufficient abundance to supply a growing and evolving population of RNAs is problematic for evolutionary hypotheses because non-enzymatic synthesis and assembly of nucleotide 5'-triphosphates (or other analogously activated phosphodiester species) is inherently difficult. However, nucleotide 2',3'-cyclic phosphates are also phosphodiesters, and are the natural and abundant products of RNA degradation. These have previously been dismissed as viable substrates for prebiotic RNA synthesis. We propose that the arguments for their dismissal are based on a flawed assumption, and that nucleotide 2',3'-cyclic phosphates in fact possess several significant, advantageous properties that indeed make them particularly viable substrates for prebiotic RNA synthesis. An RNA World hypothesis based upon the polymerization of nucleotide 2',3'-cyclic phosphates possesses additional explanatory power in that it accounts for the observed ribozyme "fossil record", suggests a viable mechanism for substrate transport across lipid vesicle boundaries of primordial proto-cells, circumvents the problems of substrate scarcity and implausible synthetic pathways, provides for a primitive but effective RNA replicase editing mechanism, and definitively explains why RNA, rather than DNA, must have been the original catalyst. Finally, our analysis compels us to propose that a fundamental and universal property that drives the evolution of living systems, as well as pre-biotic replicating molecules (be they composed of RNA or protein), is that they exploit chemical reactions that already possess competing kinetically-preferred and thermodynamically-preferred pathways in a manner that optimizes the balance between the two types of pathways. © 2014 by the authors; licensee MDPI, Basel, Switzerland.

White F.J.,University of Oregon | Waller M.,University of Oregon | Boose K.,University of Oregon | Merrill M.Y.,Cabrillo College | Wood K.D.,Horizon Inc.
Journal of Anthropological Sciences | Year: 2015

Under the social origins hypothesis, human language is thought to have evolved within the framework of non-human primate social contexts and relationships. Our two closest relatives, chimpanzees and bonobos, however, have very different social relationships and this may be reflected in their use of loud calls. Much of loud calling in the male-bonded and aggressive chimpanzee functions for male alliance formation and intercommunity aggression. Bonobos, however, are female bonded and less aggressive and little is known on the use and function of their loud calls. Data on frequencies, context, and locations of vocalizations were collected for wild bonobos, Pan paniscus, at the Lomako Forest study site in the Democratic Republic of the Congo from 1983 to 2009. Both males and females participated in loud calls used for inter-party communication. Calling and response rates by both males and females were higher during party fusion than party fission and were common at evening nesting. The distribution of loud calls within the community range of loud calls was not random with males calling significantly more towards the periphery of the range and females calling significantly more in central areas. Calling and party fission were common at food patches. Responses were more frequent for female calls than for male calls. Calling, followed by fusion, was more frequent when a small party called from a large patch. We conclude that bonobo females and males loud calls can function in inter-party communication to call others to large food patches. Females call to attract potential allies and males call to attract potential mates. Our results support the social hypothesis of the origin of language because differences in the function and use of loud calls reflect the differing social systems of chimpanzees and bonobos. Bonobo loud calls are important for female communication and function in party coordination and, unlike chimpanzees, are less important in male cooperative aggression. © 2015, Istituto Italiano di Antropologia. All rights reserved.

Bernardi G.,University of California at Santa Cruz | Bernardi G.,San Francisco State University | Ramon M.L.,University of California at Santa Cruz | Alva-Campbell Y.,University of California at Santa Cruz | And 6 more authors.
Bulletin of Marine Science | Year: 2014

Working in the Galápagos Islands and surrounding areas, we examined the relationship between population structure, a precursor to allopatric speciation, in species of reef fishes that exhibit different life history traits and three types of distributions in a nested setting: endemic (restricted to the Galápagos Islands), insular (Galápagos and neighboring islands), and Panamic (tropical eastern Pacific). We used a combination of population structure and coalescent approaches to assess the degree of genetic population structure in the three groups of fish species. In addition, we evaluated the level of inter-island genetic diversity in endemic species to determine if Galápagos fishes, like their terrestrial counterparts, could be used as a system to study allopatric speciation in the sea. We found that in general, there was no correlation between distribution ranges, life history traits, and population structure, except for Dialommus fuscus Gilbert, 1891, a Galápagos endemic that lives in the uppermost intertidal area, and as predicted, shows very strong population structure. We found the highest number of statistically significant population pairwise FST comparisons in endemic species. In addition, three out of four endemic species showed significant population pairwise FST [D. fuscus, Lepidonectes corallicola (Kendall and Radcliffe, 1912), and Lythrypnus gilbert (Heller and Snodgrass, 1903)]. These results suggest that endemic Galápagos Islands reef fishes may be a promising group of species to study phylogeographic patterns of speciation.© 2014 Rosenstiel School of Marine and Atmospheric Science of the University of Miami.

Waxman K.T.,California Institute for Nursing and Health Care | Nichols A.A.,Lucile Packard Childrens Hospital at Stanford | Nichols A.A.,San Francisco State University | O'Leary-Kelley C.,San Jose State University | Miller M.,Cabrillo College
Simulation in Healthcare | Year: 2011

The Bay Area Simulation Collaborative (BASC), established in 2007, is a group of more than 100 schools of nursing and hospitals, totaling more than 600 faculty and hospital educators, from both service and academia in the ten counties that comprise the San Francisco Bay Area. The California Institute for Nursing & Health Care leads the BASC, which was funded through a grant from the Gordon and Betty Moore Foundation. This 3-year project was designed to train and educate nursing faculty and hospital educators in the concepts of simulation. It was also designed to develop clinical simulation scenarios for use within the BASC. Finally, the project implemented a research and evaluation agenda to demonstrate that simulation makes a positive difference in the critical thinking skills of nursing students. This article will describe the evolution, purpose, and goals of the BASC and how the initial investment has been leveraged to create addition regional collaboratives in the state and ultimately, the California Simulation Alliance. Copyright © 2011 Society for Simulation in Healthcare.

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