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• 1. [Article] Postpollination Discrimination Between Self and Outcross Pollen Covaries with the Mating System of a Self-Compatible Flowering Plant

  Premise of the Study: Variation in the mating system of hermaphroditic plant populations is determined by interactions between genetic and environmental factors operating via both pre- and postmating processes. ...

  Citation × Citation Citation Abstract Copy Title: Postpollination Discrimination Between Self and Outcross Pollen Covaries with the Mating System of a Self-Compatible Flowering Plant Author: Cruzan, Mitchell B., Barrett, Spencer C. H. Year: 2016 Premise of the Study: Variation in the mating system of hermaphroditic plant populations is determined by interactions between genetic and environmental factors operating via both pre- and postmating processes. Models predicting the maintenance of intermediate outcrossing rates in animal-pollinated plants often assume that the mating system is primarily controlled by floral morphology and pollinator availability, but rarely has the influence of postpollination processes on variation in outcrossing been examined. Methods: We investigated the influence of stylar discrimination between illegitimate and legitimate pollen-tube growth and the pollen-load capacity of stigmas on mating-system variation in the annual, tristylous species Eichhornia paniculata using controlled crosses and genetic markers. This species exhibits an exceptionally broad range of outcrossing rates in natural populations. Key Results: There was significant variation among populations in the pollen-load capacity of stigmas and the ability of styles to discriminate between illegitimate vs. legitimate pollen. There was strong correspondence between stylar-discrimination ability and variation in outcrossing rate among populations and style morphs. The combination of stigmatic pollen-load capacity and stylar discrimination explained more than 80% of the variation in outcrossing rates among populations. Conclusions: The finding that stigmatic pollen-load capacity and stylar-discrimination ability contributed significantly to explaining the wide range of outcrossing rates in E. paniculata suggests that postpollination mechanisms play an important role in governing mating patterns in this species. The difference in levels of stylar discrimination between outcrossing and selfing populations may reflect a trade-off between selection for increased outcrossing and greater reproductive assurance. Title: Postpollination Discrimination Between Self and Outcross Pollen Covaries with the Mating System of a Self-Compatible Flowering Plant Author: Cruzan, Mitchell B., Barrett, Spencer C. H. Year: 2016 Premise of the Study: Variation in the mating system of hermaphroditic plant populations is determined by interactions between genetic and environmental factors operating via both pre- and postmating processes. Models predicting the maintenance of intermediate outcrossing rates in animal-pollinated plants often assume that the mating system is primarily controlled by floral morphology and pollinator availability, but rarely has the influence of postpollination processes on variation in outcrossing been examined. Methods: We investigated the influence of stylar discrimination between illegitimate and legitimate pollen-tube growth and the pollen-load capacity of stigmas on mating-system variation in the annual, tristylous species Eichhornia paniculata using controlled crosses and genetic markers. This species exhibits an exceptionally broad range of outcrossing rates in natural populations. Key Results: There was significant variation among populations in the pollen-load capacity of stigmas and the ability of styles to discriminate between illegitimate vs. legitimate pollen. There was strong correspondence between stylar-discrimination ability and variation in outcrossing rate among populations and style morphs. The combination of stigmatic pollen-load capacity and stylar discrimination explained more than 80% of the variation in outcrossing rates among populations. Conclusions: The finding that stigmatic pollen-load capacity and stylar-discrimination ability contributed significantly to explaining the wide range of outcrossing rates in E. paniculata suggests that postpollination mechanisms play an important role in governing mating patterns in this species. The difference in levels of stylar discrimination between outcrossing and selfing populations may reflect a trade-off between selection for increased outcrossing and greater reproductive assurance. Close

• 2. [Article] Photosynthesis and Respiration of Arceuthobium Tsugense

  Dark respiration rates of the aerial shoots of Arceuthobium tsugense, obtained by manometric and IRGA techniques, show production of C02to range between 155-300 µl CO2 g-1h-1 with evidence of seasonal ...

  Citation × Citation Citation Abstract Copy Title: Photosynthesis and Respiration of Arceuthobium Tsugense Author: Miller, James Roger Year: 1973 Dark respiration rates of the aerial shoots of Arceuthobium tsugense, obtained by manometric and IRGA techniques, show production of C02to range between 155-300 µl CO2 g-1h-1 with evidence of seasonal variation. Experiments with 14C02 indicate that the aerial shoots are capable of some photosynthetic CO2 fixation, with 10-15% of the available 14C incorporated by the plant tissue in one hour.The portions of the o aerial shoots which are most active in C02 fixation are the young terminal regions. Biochemical characterization of the products of photosynthesis reveals that 80-90% of the incorporated 14C is ethanol soluble. Ten percent of the ethanol fraction is lipoidal in nature, the rest is H20 soluble. Ion exchange separation of the H20 soluble portion shows that 16-25% of the 14C activity is cationic, about 25% anionic, with the balance neutral. Aspartic acid, glutamic acid, and valine are present in the cationic fraction, with additional free amino acids indicated. IRGA experiments indicate an apparent photosynthetic CO2 fixation capacity of 80-90 percent of the ethanol fraction is lipoidal in nature, the rest is H20 soluble. Ion exchange separation of the H20 soluble portion shows that 16-25% of the 14C activity is cationic, about 25% anionic, with the balance neutral. Aspartic acid, glutamic acid, and valine are present in the cationic fraction, with additional free amino acids indicated. IRGA experiments indicate an apparent photosynthetic CO2 fixation capacity of 80-90 µl CO2 g-1 h-1, or 25-30% of the amount of C02 produced by respiration. The significance of these findings is discussed with respect to nutrition of the parasite. Title: Photosynthesis and Respiration of Arceuthobium Tsugense Author: Miller, James Roger Year: 1973 Dark respiration rates of the aerial shoots of Arceuthobium tsugense, obtained by manometric and IRGA techniques, show production of C02to range between 155-300 µl CO2 g-1h-1 with evidence of seasonal variation. Experiments with 14C02 indicate that the aerial shoots are capable of some photosynthetic CO2 fixation, with 10-15% of the available 14C incorporated by the plant tissue in one hour.The portions of the o aerial shoots which are most active in C02 fixation are the young terminal regions. Biochemical characterization of the products of photosynthesis reveals that 80-90% of the incorporated 14C is ethanol soluble. Ten percent of the ethanol fraction is lipoidal in nature, the rest is H20 soluble. Ion exchange separation of the H20 soluble portion shows that 16-25% of the 14C activity is cationic, about 25% anionic, with the balance neutral. Aspartic acid, glutamic acid, and valine are present in the cationic fraction, with additional free amino acids indicated. IRGA experiments indicate an apparent photosynthetic CO2 fixation capacity of 80-90 percent of the ethanol fraction is lipoidal in nature, the rest is H20 soluble. Ion exchange separation of the H20 soluble portion shows that 16-25% of the 14C activity is cationic, about 25% anionic, with the balance neutral. Aspartic acid, glutamic acid, and valine are present in the cationic fraction, with additional free amino acids indicated. IRGA experiments indicate an apparent photosynthetic CO2 fixation capacity of 80-90 µl CO2 g-1 h-1, or 25-30% of the amount of C02 produced by respiration. The significance of these findings is discussed with respect to nutrition of the parasite. Close

• 3. [Article] A Biochemical Analysis of Viscin from Arceuthobium Tsugense

  The viscin coating of seeds from Arceuthobium tsugense was analyzed histochemically. The results indicated that the viscin is composed of two components. The first is a muculagenous pectic compound which ...

  Citation × Citation Citation Abstract Copy Title: A Biochemical Analysis of Viscin from Arceuthobium Tsugense Author: Paquet, Peter J. Year: 1975 The viscin coating of seeds from Arceuthobium tsugense was analyzed histochemically. The results indicated that the viscin is composed of two components. The first is a muculagenous pectic compound which surrounds the entire seed and accounts for a number of observed phenomenon such as stickiness, water holding capacity and the ability to undergo repeated drying and rehydration. The second component is made up of a large number of cellulose strands which are attached to the endocarp and run throughout the pectic coating. Scanning electron micrographs show that they are thought to be important in maintaining the integrity of the pectic coating. The significance of these findings is discussed with respect to establishment of the parasite. Title: A Biochemical Analysis of Viscin from Arceuthobium Tsugense Author: Paquet, Peter J. Year: 1975 The viscin coating of seeds from Arceuthobium tsugense was analyzed histochemically. The results indicated that the viscin is composed of two components. The first is a muculagenous pectic compound which surrounds the entire seed and accounts for a number of observed phenomenon such as stickiness, water holding capacity and the ability to undergo repeated drying and rehydration. The second component is made up of a large number of cellulose strands which are attached to the endocarp and run throughout the pectic coating. Scanning electron micrographs show that they are thought to be important in maintaining the integrity of the pectic coating. The significance of these findings is discussed with respect to establishment of the parasite. Close

• 4. [Article] Androgen-induced immunosuppression

  It is well established that females are more immunocompetent than males as evidenced by higher humoral antibody titers, lowered susceptibility to infection, and more efficient graft rejection. Furthermore, ...

  Citation × Citation Citation Abstract Copy Title: Androgen-induced immunosuppression Author: Weyant, Debra Ann Year: 1979 It is well established that females are more immunocompetent than males as evidenced by higher humoral antibody titers, lowered susceptibility to infection, and more efficient graft rejection. Furthermore, females also exhibit a much higher incidence of autoimmune disease. These observations have led investigators to believe that the male hormonal environment may play a key role in the regulation of immune response. For this reason, this study is concerned with the expression of autoimmunity and of immune function in the mouse. This study included the New Zealand Black (NZB) mouse strain, as an animal model for human SLE, as well as normal DBA/2 and Balb/c strains. Animals were administered testosterone via subcutaneous implants in silastic tubing or by injection. Mice used were intact females, intact males and castrated males. Animals were otherwise untreated or had been exposed to a sublethal dose (400-550 rads) of irradiation. Target organ weight changes, immune capacity and peripheral blood picture changes were measured. Title: Androgen-induced immunosuppression Author: Weyant, Debra Ann Year: 1979 It is well established that females are more immunocompetent than males as evidenced by higher humoral antibody titers, lowered susceptibility to infection, and more efficient graft rejection. Furthermore, females also exhibit a much higher incidence of autoimmune disease. These observations have led investigators to believe that the male hormonal environment may play a key role in the regulation of immune response. For this reason, this study is concerned with the expression of autoimmunity and of immune function in the mouse. This study included the New Zealand Black (NZB) mouse strain, as an animal model for human SLE, as well as normal DBA/2 and Balb/c strains. Animals were administered testosterone via subcutaneous implants in silastic tubing or by injection. Mice used were intact females, intact males and castrated males. Animals were otherwise untreated or had been exposed to a sublethal dose (400-550 rads) of irradiation. Target organ weight changes, immune capacity and peripheral blood picture changes were measured. Close

• 5. [Article] Taxis Toward Hydrogen Gas by Methanococcus Maripaludis

  Knowledge of taxis (directed swimming) in the Archaea is currently expanding through identification of novel receptors, effectors, and proteins involved in signal transduction to the flagellar motor. Although ...

  Citation × Citation Citation Abstract Copy Title: Taxis Toward Hydrogen Gas by Methanococcus Maripaludis Author: Brileya, Kristen A., Connolly, James M., Downey, Carey, Gerlach, Robin, Fields, Matthew W. Year: 2013 Knowledge of taxis (directed swimming) in the Archaea is currently expanding through identification of novel receptors, effectors, and proteins involved in signal transduction to the flagellar motor. Although the ability for biological cells to sense and swim toward hydrogen gas has been hypothesized for many years, this capacity has yet to be observed and demonstrated. Here we show that the average swimming velocity increases in the direction of a source of hydrogen gas for the methanogen, Methanococcus maripaludis using a capillary assay with anoxic gas-phase control and time-lapse microscopy. The results indicate that a methanogen couples motility to hydrogen concentration sensing and is the first direct observation of hydrogenotaxis in any domain of life. Hydrogenotaxis represents a strategy that would impart a competitive advantage to motile microorganisms that compete for hydrogen gas and would impact the C, S and N cycles. Title: Taxis Toward Hydrogen Gas by Methanococcus Maripaludis Author: Brileya, Kristen A., Connolly, James M., Downey, Carey, Gerlach, Robin, Fields, Matthew W. Year: 2013 Knowledge of taxis (directed swimming) in the Archaea is currently expanding through identification of novel receptors, effectors, and proteins involved in signal transduction to the flagellar motor. Although the ability for biological cells to sense and swim toward hydrogen gas has been hypothesized for many years, this capacity has yet to be observed and demonstrated. Here we show that the average swimming velocity increases in the direction of a source of hydrogen gas for the methanogen, Methanococcus maripaludis using a capillary assay with anoxic gas-phase control and time-lapse microscopy. The results indicate that a methanogen couples motility to hydrogen concentration sensing and is the first direct observation of hydrogenotaxis in any domain of life. Hydrogenotaxis represents a strategy that would impart a competitive advantage to motile microorganisms that compete for hydrogen gas and would impact the C, S and N cycles. Close

• 6. [Article] Hypoxia and Anoxia Tolerance in the Annual Killifish Austrofundulus Limnaeus

  Embryos of the annual killifish Austrofundulus limnaeus are routinely exposed to oxygen limitation during development and are extremely tolerant of anoxia. Importantly, tolerance of anoxia is not strictly ...

  Citation × Citation Citation Abstract Copy Title: Hypoxia and Anoxia Tolerance in the Annual Killifish Austrofundulus Limnaeus Author: Podrabsky, Jason E., Wilson, Natalie E. Year: 2016 Embryos of the annual killifish Austrofundulus limnaeus are routinely exposed to oxygen limitation during development and are extremely tolerant of anoxia. Importantly, tolerance of anoxia is not strictly associated with entrance into metabolic dormancy associated with diapause II, but rather any embryo will respond to anoxia by entering into a state of anoxia-induced quiescence. Hypoxia causes a reduction in the rate of development, reduced heart rates, and reduced capacities for metabolic enzyme activity in both aerobic and anaerobic pathways. Embryos of A. limnaeus begin life as oxyconformers, and transition into oxyregulators near the completion of embryonic development. As this transition occurs, extreme anoxia tolerance is lost. The rate of early development is independent of oxygen partial pressure, despite the fact that the embryos are oxyconformers. This suggests a contribution from anaerobic pathways to support early development. However, the specific pathways supporting this metabolism are unknown. The response of A. limnaeus embryos to hypoxia and anoxia is unique compared to other fishes and most other vertebrates, and thus future studies on this species may lend insight into novel mechanisms that support survival during prolonged oxygen limitation. Title: Hypoxia and Anoxia Tolerance in the Annual Killifish Austrofundulus Limnaeus Author: Podrabsky, Jason E., Wilson, Natalie E. Year: 2016 Embryos of the annual killifish Austrofundulus limnaeus are routinely exposed to oxygen limitation during development and are extremely tolerant of anoxia. Importantly, tolerance of anoxia is not strictly associated with entrance into metabolic dormancy associated with diapause II, but rather any embryo will respond to anoxia by entering into a state of anoxia-induced quiescence. Hypoxia causes a reduction in the rate of development, reduced heart rates, and reduced capacities for metabolic enzyme activity in both aerobic and anaerobic pathways. Embryos of A. limnaeus begin life as oxyconformers, and transition into oxyregulators near the completion of embryonic development. As this transition occurs, extreme anoxia tolerance is lost. The rate of early development is independent of oxygen partial pressure, despite the fact that the embryos are oxyconformers. This suggests a contribution from anaerobic pathways to support early development. However, the specific pathways supporting this metabolism are unknown. The response of A. limnaeus embryos to hypoxia and anoxia is unique compared to other fishes and most other vertebrates, and thus future studies on this species may lend insight into novel mechanisms that support survival during prolonged oxygen limitation. Close

• 7. [Article] Rapid and Repeatable Shifts in Life-History Timing of <i>Rhagoletis pomonella</i> (Diptera: Tephritidae) Following Colonization of Novel Host Plants in the Pacific Northwestern United States

  Host shifts of phytophagous insect specialists to novel plants can result in divergent ecological adaptation, generating reproductive isolation and potentially new species. Rhagoletis pomonellafruit flies ...

  Citation × Citation Citation Abstract Copy Title: Rapid and Repeatable Shifts in Life-History Timing of <i>Rhagoletis pomonella</i> (Diptera: Tephritidae) Following Colonization of Novel Host Plants in the Pacific Northwestern United States Author: Mattsson, Monte, Hood, Glen R., Feder, Jeffery L., Ruedas, Luis A. Year: 2015 Host shifts of phytophagous insect specialists to novel plants can result in divergent ecological adaptation, generating reproductive isolation and potentially new species. Rhagoletis pomonellafruit flies in eastern North America underwent a host shift ~160 ya from native downy hawthorn (Crataegus mollis) to introduced, domesticated apple (Malus domestica). Divergent selection on diapause phenology related to the earlier fruiting time of apples versus downy hawthorns resulted in partial allochronic reproductive isolation between the fly races. Here, we test for how rapid and repeatable shifts in life-history timing are driving ecological divergence of R. pomonella in the Pacific Northwestern USA. The fly was introduced into the region via larval-infested apples 40–65 ya and now attacks native black hawthorn (Crataegus douglasii) and introduced ornamental hawthorn (Crataegus monogyna), in addition to early- and late-maturing apple varieties in the region. To investigate the life-history timing hypothesis, we used a field-based experiment to characterize the host-associated eclosion and flight activity patterns of adults, and the feeding times of larvae at a field site in Vancouver, Washington. We also assessed the degree to which differences in host-fruiting time generate allochronic isolation among apple-, black hawthorn-, and ornamental hawthorn-associated fly populations. We conclude that host-associated fly populations are temporally offset 24.4% to 92.6% in their seasonal distributions. Our results imply that R. pomonella possesses the capacity for rapid and repeatable shifts in diapause life history to match host-fruiting phenology, which can generate ecologically based reproductive isolation, and potentially biodiversity in the process. Title: Rapid and Repeatable Shifts in Life-History Timing of <i>Rhagoletis pomonella</i> (Diptera: Tephritidae) Following Colonization of Novel Host Plants in the Pacific Northwestern United States Author: Mattsson, Monte, Hood, Glen R., Feder, Jeffery L., Ruedas, Luis A. Year: 2015 Host shifts of phytophagous insect specialists to novel plants can result in divergent ecological adaptation, generating reproductive isolation and potentially new species. Rhagoletis pomonellafruit flies in eastern North America underwent a host shift ~160 ya from native downy hawthorn (Crataegus mollis) to introduced, domesticated apple (Malus domestica). Divergent selection on diapause phenology related to the earlier fruiting time of apples versus downy hawthorns resulted in partial allochronic reproductive isolation between the fly races. Here, we test for how rapid and repeatable shifts in life-history timing are driving ecological divergence of R. pomonella in the Pacific Northwestern USA. The fly was introduced into the region via larval-infested apples 40–65 ya and now attacks native black hawthorn (Crataegus douglasii) and introduced ornamental hawthorn (Crataegus monogyna), in addition to early- and late-maturing apple varieties in the region. To investigate the life-history timing hypothesis, we used a field-based experiment to characterize the host-associated eclosion and flight activity patterns of adults, and the feeding times of larvae at a field site in Vancouver, Washington. We also assessed the degree to which differences in host-fruiting time generate allochronic isolation among apple-, black hawthorn-, and ornamental hawthorn-associated fly populations. We conclude that host-associated fly populations are temporally offset 24.4% to 92.6% in their seasonal distributions. Our results imply that R. pomonella possesses the capacity for rapid and repeatable shifts in diapause life history to match host-fruiting phenology, which can generate ecologically based reproductive isolation, and potentially biodiversity in the process. Close

• 8. [Article] Isolation of Diverse Members of the Aquificales from Geothermal Springs in Tengchong, China

  The order Aquificales (phylum Aquificae) consists of thermophilic and hyperthermophilic bacteria that are prominent in many geothermal systems, including those in Tengchong, Yunnan Province, China. However, ...

  Citation × Citation Citation Abstract Copy Title: Isolation of Diverse Members of the Aquificales from Geothermal Springs in Tengchong, China Author: Hedlund, Brian P., Reysenbach, Anna-Louise, Huang, Liuquin, Ong, John C., Liu, Zizhang, Dodsworth, Jeremy A., Ahmed, Reham, Williams, Amanda J., Briggs, Brandon R., Liu, Yitai, Hou, Weiguo, Dong, Hailiang Year: 2015 The order Aquificales (phylum Aquificae) consists of thermophilic and hyperthermophilic bacteria that are prominent in many geothermal systems, including those in Tengchong, Yunnan Province, China. However, Aquificales have not previously been isolated from Tengchong. We isolated five strains of Aquificales from diverse springs (temperature 45.2–83.3°C and pH 2.6–9.1) in the Rehai Geothermal Field from sites in which Aquificales were abundant. Phylogenetic analysis showed that four of the strains belong to the genera Hydrogenobacter, Hydrogenobaculum, andSulfurihydrogenibium, including strains distant enough to likely justify new species ofHydrogenobacter and Hydrogenobaculum. The additional strain may represent a new genus in theHydrogenothermaceae. All strains were capable of aerobic respiration under microaerophilic conditions; however, they had variable capacity for chemolithotrophic oxidation of hydrogen and sulfur compounds and nitrate reduction. Title: Isolation of Diverse Members of the Aquificales from Geothermal Springs in Tengchong, China Author: Hedlund, Brian P., Reysenbach, Anna-Louise, Huang, Liuquin, Ong, John C., Liu, Zizhang, Dodsworth, Jeremy A., Ahmed, Reham, Williams, Amanda J., Briggs, Brandon R., Liu, Yitai, Hou, Weiguo, Dong, Hailiang Year: 2015 The order Aquificales (phylum Aquificae) consists of thermophilic and hyperthermophilic bacteria that are prominent in many geothermal systems, including those in Tengchong, Yunnan Province, China. However, Aquificales have not previously been isolated from Tengchong. We isolated five strains of Aquificales from diverse springs (temperature 45.2–83.3°C and pH 2.6–9.1) in the Rehai Geothermal Field from sites in which Aquificales were abundant. Phylogenetic analysis showed that four of the strains belong to the genera Hydrogenobacter, Hydrogenobaculum, andSulfurihydrogenibium, including strains distant enough to likely justify new species ofHydrogenobacter and Hydrogenobaculum. The additional strain may represent a new genus in theHydrogenothermaceae. All strains were capable of aerobic respiration under microaerophilic conditions; however, they had variable capacity for chemolithotrophic oxidation of hydrogen and sulfur compounds and nitrate reduction. Close

• 9. [Article] A <i>Francisella</i>-Like Endosymbiont in the Gulf Coast Tick Evolved From a Mammalian Pathogen

  Ticks (order Ixodida) vector pathogenic bacteria that cause diseases in humans and other mammals. They also contain bacteria that are closely related to pathogens but function as endosymbionts that provide ...

  Citation × Citation Citation Abstract Copy Title: A <i>Francisella</i>-Like Endosymbiont in the Gulf Coast Tick Evolved From a Mammalian Pathogen Author: Gerhart, Jonathan G., Moses, Abraham S., Raghavan, Rahul Year: 2016 Ticks (order Ixodida) vector pathogenic bacteria that cause diseases in humans and other mammals. They also contain bacteria that are closely related to pathogens but function as endosymbionts that provide nutrients that are missing from mammalian blood—their sole food source. For instance, mammalian pathogens such as Coxiella burnetii and Francisella tularensis, as well as Coxiella-like and Francisella-like endosymbionts (CLEs and FLEs, respectively) occur in ticks worldwide. However, it is not clear whether the pathogens evolved from symbionts or symbionts from pathogens. Recent studies have indicated that C. burnetii likely originated from a tick-associated ancestor, but the origins of FLEs are not clear. In this study, we sequenced the genome of an FLE, termed FLE-Am, present in the Gulf Coast tick, Amblyomma maculatum. We show that FLE-Am likely evolved from a pathogenic strain of Francisella, indicating that tick endosymbionts can evolve from mammalian pathogens. Although the genome of FLE-Am is almost the same size as the genomes of pathogenic Francisella strains, about one-third of its protein-coding genes contain inactivating mutations. The relatively low coding capacity and extensive metabolic capabilities indicate that FLE-Am transitioned recently to its current endosymbiotic lifestyle and likely replaced an ancient endosymbiont with degraded functionality. Title: A <i>Francisella</i>-Like Endosymbiont in the Gulf Coast Tick Evolved From a Mammalian Pathogen Author: Gerhart, Jonathan G., Moses, Abraham S., Raghavan, Rahul Year: 2016 Ticks (order Ixodida) vector pathogenic bacteria that cause diseases in humans and other mammals. They also contain bacteria that are closely related to pathogens but function as endosymbionts that provide nutrients that are missing from mammalian blood—their sole food source. For instance, mammalian pathogens such as Coxiella burnetii and Francisella tularensis, as well as Coxiella-like and Francisella-like endosymbionts (CLEs and FLEs, respectively) occur in ticks worldwide. However, it is not clear whether the pathogens evolved from symbionts or symbionts from pathogens. Recent studies have indicated that C. burnetii likely originated from a tick-associated ancestor, but the origins of FLEs are not clear. In this study, we sequenced the genome of an FLE, termed FLE-Am, present in the Gulf Coast tick, Amblyomma maculatum. We show that FLE-Am likely evolved from a pathogenic strain of Francisella, indicating that tick endosymbionts can evolve from mammalian pathogens. Although the genome of FLE-Am is almost the same size as the genomes of pathogenic Francisella strains, about one-third of its protein-coding genes contain inactivating mutations. The relatively low coding capacity and extensive metabolic capabilities indicate that FLE-Am transitioned recently to its current endosymbiotic lifestyle and likely replaced an ancient endosymbiont with degraded functionality. Close

• 10. [Article] Stranding Mortality Patterns in California Sea Lions and Steller Sea Lions in Oregon and Southern Washington, 2006 to 2014

  As changing ocean conditions lead to declining fish stocks and movement of forage fish, sea lions on the Oregon coast are subject to the pressures of declining prey availability and increasing conflicts ...

  Citation × Citation Citation Abstract Copy Title: Stranding Mortality Patterns in California Sea Lions and Steller Sea Lions in Oregon and Southern Washington, 2006 to 2014 Author: Lee, Kessina Year: 2016 As changing ocean conditions lead to declining fish stocks and movement of forage fish, sea lions on the Oregon coast are subject to the pressures of declining prey availability and increasing conflicts with commercial and recreational fisheries. An analysis of strandings of California sea lions, Zalophus californianus, and Steller sea lions, Eumetopias jubatus, from 2006 to 2014, included cause of death, changing ocean conditions, and anthropogenic activity. Causes of death included disease, injury, and human interaction, such as gunshot wounds, fisheries net entanglements and boat strikes. Oregon and Washington strandings of California sea lions are primarily adult and subadult males that migrate north from California rookeries, while Steller sea lions are year-round residents and strandings are comprised of males and females of all ages. While the California sea lion population is currently at or near carrying capacity, the Eastern Pacific population of Steller sea lions was designated as Threatened under the Endangered Species Act until October 2013. Understanding impacts to these two pinniped species is vital to implementing effective management and conservation policies. Oregon and southern Washington strandings of California sea lions and Steller sea lions from 2006 to 2014 were analyzed spatially using the geographic information system (GIS), and temporally to identify possible correlations with prey availability and human interaction. Strandings were found to follow seasonal patterns from year to year: Steller sea lion strandings were highest from May to July, California sea lions peaked in September, October, and November. There was a correlation between significantly high numbers of strandings and the three largest commercial fisheries in Oregon: Chinook salmon, Coho salmon, and Dungeness crab. This analysis provides a format for continuing to monitor primary ecological and anthropogenic drivers of pinniped mortality in Oregon and southern Washington. Title: Stranding Mortality Patterns in California Sea Lions and Steller Sea Lions in Oregon and Southern Washington, 2006 to 2014 Author: Lee, Kessina Year: 2016 As changing ocean conditions lead to declining fish stocks and movement of forage fish, sea lions on the Oregon coast are subject to the pressures of declining prey availability and increasing conflicts with commercial and recreational fisheries. An analysis of strandings of California sea lions, Zalophus californianus, and Steller sea lions, Eumetopias jubatus, from 2006 to 2014, included cause of death, changing ocean conditions, and anthropogenic activity. Causes of death included disease, injury, and human interaction, such as gunshot wounds, fisheries net entanglements and boat strikes. Oregon and Washington strandings of California sea lions are primarily adult and subadult males that migrate north from California rookeries, while Steller sea lions are year-round residents and strandings are comprised of males and females of all ages. While the California sea lion population is currently at or near carrying capacity, the Eastern Pacific population of Steller sea lions was designated as Threatened under the Endangered Species Act until October 2013. Understanding impacts to these two pinniped species is vital to implementing effective management and conservation policies. Oregon and southern Washington strandings of California sea lions and Steller sea lions from 2006 to 2014 were analyzed spatially using the geographic information system (GIS), and temporally to identify possible correlations with prey availability and human interaction. Strandings were found to follow seasonal patterns from year to year: Steller sea lion strandings were highest from May to July, California sea lions peaked in September, October, and November. There was a correlation between significantly high numbers of strandings and the three largest commercial fisheries in Oregon: Chinook salmon, Coho salmon, and Dungeness crab. This analysis provides a format for continuing to monitor primary ecological and anthropogenic drivers of pinniped mortality in Oregon and southern Washington. Close