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• 21. [Article] The Hyperthermophilic Archaeon Sulfolobus : from Exploration to Exploitation

  In the early 1970s, Sulfolobus was first isolated by Thomas Brock and co-workers from sulfur-rich acidic hot springs in Yellowstone National Park. Sulfolobus became one of the model organisms of Archaea ...

  Citation × Citation Citation Abstract Copy Title: The Hyperthermophilic Archaeon Sulfolobus : from Exploration to Exploitation Author: Brouns, Stan J.J., Ettema, Thijs J.G., Stedman, Kenneth M., Walther, Jasper, Smith, Hauke, Snijders, Ambrosius P.L., Young, Mark, Bernander, Rolf, Wright, Phillip C., Siebers, Betina, Van der Oost, John Year: 2003 In the early 1970s, Sulfolobus was first isolated by Thomas Brock and co-workers from sulfur-rich acidic hot springs in Yellowstone National Park. Sulfolobus became one of the model organisms of Archaea in general, and of Crenarchaea in particular. Many of its unusual physiological characteristics have been investigated, and several of its thermostable enzymes have been studied in considerable detail. For fundamental reasons, and because of its potential for industrial applications, Sulfolobus has been selected for a genome sequence project. The recent completion of the Sulfolobus solfataricus genome has set the stage for a series of postgenome research lines that will be reviewed here. Comparative genomics aims to unravel the cell’s metabolic potential (enzymes, pathways, and regulation) and compare it to other organisms. This in silico analysis of Sulfolobus has revealed several unique metabolic features and confirmed that the major control processes (transcription, translation, and replication) resemble eukaryal much more than bacterial equivalents. Currently, several research groups use a functional genomics approach—a genomebased, high-throughput analysis of the complete Sulfolobus cell—at the level of RNA (transcriptomics), protein (proteomics), and metabolic intermediates and products (metabolomics). Apart from analyzing the cell’s response to different cultivation conditions, the comparison of different genotypes (wild type and mutants) would be very interesting for both basic science and applied reasons. Much effort has recently been put into the establishment of tools that allow genetic engineering of Sulfolobus. The future challenge is to integrate available knowledge in order to understand the relevant mechanisms that enable Sulfolobus to thrive in its extreme habitats. Moreover, such a Systems Biology approach is essential as a basis for the directed engineering and industrial exploitation of this unique microorganism. Title: The Hyperthermophilic Archaeon Sulfolobus : from Exploration to Exploitation Author: Brouns, Stan J.J., Ettema, Thijs J.G., Stedman, Kenneth M., Walther, Jasper, Smith, Hauke, Snijders, Ambrosius P.L., Young, Mark, Bernander, Rolf, Wright, Phillip C., Siebers, Betina, Van der Oost, John Year: 2003 In the early 1970s, Sulfolobus was first isolated by Thomas Brock and co-workers from sulfur-rich acidic hot springs in Yellowstone National Park. Sulfolobus became one of the model organisms of Archaea in general, and of Crenarchaea in particular. Many of its unusual physiological characteristics have been investigated, and several of its thermostable enzymes have been studied in considerable detail. For fundamental reasons, and because of its potential for industrial applications, Sulfolobus has been selected for a genome sequence project. The recent completion of the Sulfolobus solfataricus genome has set the stage for a series of postgenome research lines that will be reviewed here. Comparative genomics aims to unravel the cell’s metabolic potential (enzymes, pathways, and regulation) and compare it to other organisms. This in silico analysis of Sulfolobus has revealed several unique metabolic features and confirmed that the major control processes (transcription, translation, and replication) resemble eukaryal much more than bacterial equivalents. Currently, several research groups use a functional genomics approach—a genomebased, high-throughput analysis of the complete Sulfolobus cell—at the level of RNA (transcriptomics), protein (proteomics), and metabolic intermediates and products (metabolomics). Apart from analyzing the cell’s response to different cultivation conditions, the comparison of different genotypes (wild type and mutants) would be very interesting for both basic science and applied reasons. Much effort has recently been put into the establishment of tools that allow genetic engineering of Sulfolobus. The future challenge is to integrate available knowledge in order to understand the relevant mechanisms that enable Sulfolobus to thrive in its extreme habitats. Moreover, such a Systems Biology approach is essential as a basis for the directed engineering and industrial exploitation of this unique microorganism. Close

• 22. [Article] Some Coyote Food Habitat Patterns in the Shrub-Steppe of South-central Washington

  Coyote food habits were ascertained by identifying the undigested material in 1143 scats collected at monthly intervals from specific road transects on the USERDA Hanford Reservation in Washington from ...

  Citation × Citation Citation Abstract Copy Title: Some Coyote Food Habitat Patterns in the Shrub-Steppe of South-central Washington Author: Stoel, Peter Frederick Year: 1976 Coyote food habits were ascertained by identifying the undigested material in 1143 scats collected at monthly intervals from specific road transects on the USERDA Hanford Reservation in Washington from 1974 to 1976. Tracks at artificially established scent posts along the principal transect provided evidence that the scats were left by coyotes and not bobcats or badgers. On the basin plain (150m elevation) where the Aptemisia tpidentata/Poa sandbepgii Association predominates, the average monthly percent occurrences in the 491 scats collected in 1975 2 were pocket mouse 60, leporid 39, pocket gopher 12, grasshopper 12, fruit 10, cricetine mice 7, darkling beetle 6, bird 5, reptile 4, ground squirrel 4, microtine mice 3, and livestock 1.8. Pocket mice and leporids both occurred in every monthly sample of 1974-76. During the summer of 1974 grasshoppers were eaten in large quantities (85 percent occurrence), but the next year they were eaten less than half as frequently (37 percent) during the same period. Monthly numbers of pocket mice and cricetines live-trapped on a grid on the plain correlated significantly with the monthly percent occurrence in scats (r = .80, P < .001; and r = .~2, P < .02 respectively). Title: Some Coyote Food Habitat Patterns in the Shrub-Steppe of South-central Washington Author: Stoel, Peter Frederick Year: 1976 Coyote food habits were ascertained by identifying the undigested material in 1143 scats collected at monthly intervals from specific road transects on the USERDA Hanford Reservation in Washington from 1974 to 1976. Tracks at artificially established scent posts along the principal transect provided evidence that the scats were left by coyotes and not bobcats or badgers. On the basin plain (150m elevation) where the Aptemisia tpidentata/Poa sandbepgii Association predominates, the average monthly percent occurrences in the 491 scats collected in 1975 2 were pocket mouse 60, leporid 39, pocket gopher 12, grasshopper 12, fruit 10, cricetine mice 7, darkling beetle 6, bird 5, reptile 4, ground squirrel 4, microtine mice 3, and livestock 1.8. Pocket mice and leporids both occurred in every monthly sample of 1974-76. During the summer of 1974 grasshoppers were eaten in large quantities (85 percent occurrence), but the next year they were eaten less than half as frequently (37 percent) during the same period. Monthly numbers of pocket mice and cricetines live-trapped on a grid on the plain correlated significantly with the monthly percent occurrence in scats (r = .80, P < .001; and r = .~2, P < .02 respectively). Close

• 23. [Article] Some physical and biological factors affecting red-tailed hawk productivity

  Various physical and biological factors affecting annual productivity in a Red-tailed Hawk population in north-central Oregon were investigated. The percentage of the population successfully fledging one ...

  Citation × Citation Citation Abstract Copy Title: Some physical and biological factors affecting red-tailed hawk productivity Author: Janes, Stewart Wayne Year: 1979 Various physical and biological factors affecting annual productivity in a Red-tailed Hawk population in north-central Oregon were investigated. The percentage of the population successfully fledging one or more young was the most important factor in determining the number of young fledged per pair in a given year. Neither clutch size nor the number of young fledged per successful nest varied significantly. Percent pair success was correlated with several January weather variables. A cold and dry January is positively correlated with Red-tailed Hawk productivity. This is apparently related to the onset of rapid vegetative growth and this in turn is positively correlated with the timing of the emergence and reproductive cycle of the principal prey, Belding’s and Townsend's ground squirrels, (Turner 1972). Because a cold and dry January delays the emergence of ground squirrels, the period of emergence and dispersal of the young squirrels more closely corresponds to the time of peak food needs of the young Red-tailed Hawks, and greater pair success is observed. This relative abundance of prey appears to be of greater importance than actual abundance. Red-tailed Hawk productivity was found to correlate significantly with two habitat variables & the presence of adequate numbers of dispersed hunting perches and relative ground squirrel abundance. The presence of one or more perches per sixteenth section provided the best single correlation. Neither territory size nor competition from interspecifically territorial Swainson's Hawks were correlated with productivity of Red-tailed Hawk territories. Red-tailed Hawks with inhabited dwellings within their territories fledged significantly more young than those without. Title: Some physical and biological factors affecting red-tailed hawk productivity Author: Janes, Stewart Wayne Year: 1979 Various physical and biological factors affecting annual productivity in a Red-tailed Hawk population in north-central Oregon were investigated. The percentage of the population successfully fledging one or more young was the most important factor in determining the number of young fledged per pair in a given year. Neither clutch size nor the number of young fledged per successful nest varied significantly. Percent pair success was correlated with several January weather variables. A cold and dry January is positively correlated with Red-tailed Hawk productivity. This is apparently related to the onset of rapid vegetative growth and this in turn is positively correlated with the timing of the emergence and reproductive cycle of the principal prey, Belding’s and Townsend's ground squirrels, (Turner 1972). Because a cold and dry January delays the emergence of ground squirrels, the period of emergence and dispersal of the young squirrels more closely corresponds to the time of peak food needs of the young Red-tailed Hawks, and greater pair success is observed. This relative abundance of prey appears to be of greater importance than actual abundance. Red-tailed Hawk productivity was found to correlate significantly with two habitat variables & the presence of adequate numbers of dispersed hunting perches and relative ground squirrel abundance. The presence of one or more perches per sixteenth section provided the best single correlation. Neither territory size nor competition from interspecifically territorial Swainson's Hawks were correlated with productivity of Red-tailed Hawk territories. Red-tailed Hawks with inhabited dwellings within their territories fledged significantly more young than those without. Close

• 24. [Article] Nest Reuse by Eastern Kingbirds: Adaptive Behavior or Ecological Constraint?

  The reuse of old nests by open-cup nesting passerines is a seemingly rare but potentially adaptive behavior if, as a consequence, females begin to breed earlier, lay larger clutches, or fledge more young. ...

  Citation × Citation Citation Abstract Copy Title: Nest Reuse by Eastern Kingbirds: Adaptive Behavior or Ecological Constraint? Author: Redmond, Lucas J., Murphy, Michael T., Dolan, Amy C. Year: 2007 The reuse of old nests by open-cup nesting passerines is a seemingly rare but potentially adaptive behavior if, as a consequence, females begin to breed earlier, lay larger clutches, or fledge more young. We report an unusually high rate of nest reuse (~10% of 341 nests) for Eastern Kingbirds (Tyrannus tyrannus) breeding at Malheur National Wildlife Refuge, Oregon. We found no difference in availability of nesting habitat or food abundance in territories in which nests were and were not reused. We also found no support for the hypotheses that kingbirds benefited from nest reuse by breeding earlier, laying larger clutches, or fledging more young, and, contrary to expectations, females that reused nests laid significantly smaller eggs than females who built their own nests. Nest reuse was independent of age: a roughly equal number of females for which we had multiple years of data both reused nests and built new nests, but at different points in their lives. Competition for nest sites seems high at Malheur National Wildlife Refuge because many open-cup nesting species utilize similar nest sites in the limited zone of riparian vegetation. A shortage of high-quality nest sites, coupled with interspecific competition, may underlie the high frequency of nest reuse in this kingbird population. Title: Nest Reuse by Eastern Kingbirds: Adaptive Behavior or Ecological Constraint? Author: Redmond, Lucas J., Murphy, Michael T., Dolan, Amy C. Year: 2007 The reuse of old nests by open-cup nesting passerines is a seemingly rare but potentially adaptive behavior if, as a consequence, females begin to breed earlier, lay larger clutches, or fledge more young. We report an unusually high rate of nest reuse (~10% of 341 nests) for Eastern Kingbirds (Tyrannus tyrannus) breeding at Malheur National Wildlife Refuge, Oregon. We found no difference in availability of nesting habitat or food abundance in territories in which nests were and were not reused. We also found no support for the hypotheses that kingbirds benefited from nest reuse by breeding earlier, laying larger clutches, or fledging more young, and, contrary to expectations, females that reused nests laid significantly smaller eggs than females who built their own nests. Nest reuse was independent of age: a roughly equal number of females for which we had multiple years of data both reused nests and built new nests, but at different points in their lives. Competition for nest sites seems high at Malheur National Wildlife Refuge because many open-cup nesting species utilize similar nest sites in the limited zone of riparian vegetation. A shortage of high-quality nest sites, coupled with interspecific competition, may underlie the high frequency of nest reuse in this kingbird population. Close

• 25. [Article] Rare, Threatened and Endangered Species of Oregon

  Extinction is a natural process. Today, however, plant and animal species are disappearing world-wide at an accelerated pace. Based on current trends, half of the species on earth will be extinct within ...

  Citation × Citation Citation Abstract Copy Title: Rare, Threatened and Endangered Species of Oregon Author: Kagan, James S., Vrilakas, Sue, Gaines, Eleanor P., Alton, Cliff, McArthur, Fern, Walsh, Kuuipo, Scheuering, Eric, Christy, John A., Hak, Jon, Tobalske, Claudine, Weiland, Annie, Koloszar, Theresa, Oregon Natural Heritage Information Center Year: 2004 Extinction is a natural process. Today, however, plant and animal species are disappearing world-wide at an accelerated pace. Based on current trends, half of the species on earth will be extinct within the next 100 years. The major cause of this phenomenon is large-scale destruction of native habitats, which has increased since European settlement began in the mid 1800's - in Oregon and throughout the New World. Once lost, a species can never be recovered, and there is no way of knowing how useful it may have been. We do know that human beings and many of their industries depend on plant and animal products. About 50% of all pharmaceuticals have a natural component as an active ingredient, yet less than one percent of the world's species have been chemically analyzed and tested. Many invertebrates and plants contain undescribed and highly functional compounds. Limnanthes floccosa subsp. grandiflora, or wooly meadow-foam, a rare plant that grows in southwest Oregon, has been recently found to produce a hybrid with the more common member of the genus, Limnanthes alba. This hybrid grows well in the poorly drained soils of the Willamette Valley and produces a valuable oil used for soaps, plastic and rubber production. In addition, the new hybrid meadow-foam does not require the field burning necessary for other crops. This species, and many other Oregon natives, will be lost without intervention. The purpose of this publication is to provide land managers, owners and interested parties with a list of those species in Oregon which are in greatest jeopardy. Title: Rare, Threatened and Endangered Species of Oregon Author: Kagan, James S., Vrilakas, Sue, Gaines, Eleanor P., Alton, Cliff, McArthur, Fern, Walsh, Kuuipo, Scheuering, Eric, Christy, John A., Hak, Jon, Tobalske, Claudine, Weiland, Annie, Koloszar, Theresa, Oregon Natural Heritage Information Center Year: 2004 Extinction is a natural process. Today, however, plant and animal species are disappearing world-wide at an accelerated pace. Based on current trends, half of the species on earth will be extinct within the next 100 years. The major cause of this phenomenon is large-scale destruction of native habitats, which has increased since European settlement began in the mid 1800's - in Oregon and throughout the New World. Once lost, a species can never be recovered, and there is no way of knowing how useful it may have been. We do know that human beings and many of their industries depend on plant and animal products. About 50% of all pharmaceuticals have a natural component as an active ingredient, yet less than one percent of the world's species have been chemically analyzed and tested. Many invertebrates and plants contain undescribed and highly functional compounds. Limnanthes floccosa subsp. grandiflora, or wooly meadow-foam, a rare plant that grows in southwest Oregon, has been recently found to produce a hybrid with the more common member of the genus, Limnanthes alba. This hybrid grows well in the poorly drained soils of the Willamette Valley and produces a valuable oil used for soaps, plastic and rubber production. In addition, the new hybrid meadow-foam does not require the field burning necessary for other crops. This species, and many other Oregon natives, will be lost without intervention. The purpose of this publication is to provide land managers, owners and interested parties with a list of those species in Oregon which are in greatest jeopardy. Close

• 26. [Article] Rare, Threatened and Endangered Plants and Animals of Oregon

  Extinction is a natural process. Today, however, plant and animal species are disappearing world-wide at an accelerated pace. Based on current trends, half of the species on earth will be extinct within ...

  Citation × Citation Citation Abstract Copy Title: Rare, Threatened and Endangered Plants and Animals of Oregon Author: Kagan, James S., Vrilakas, Sue, Gaines, Eleanor P., Alton, Cliff, Popper, Ken, Stern, Mark A., Scheuering, Eric, Christy, John A., Finnerty, Mary, Hak, Jon, Tovar, Anthony A., Murray, Michael, Tobalske, Claudine, Oregon Natural Heritage Program Year: 2001 Extinction is a natural process. Today, however, plant and animal species are disappearing world-wide at an accelerated pace. Based on current trends, half of the species on earth will be extinct within the next 100 years. The major cause of this phenomenon is large-scale destruction of native habitats, which has increased since European settlement began in the mid 1800's - in Oregon and throughout the New World. Once lost, a species can never be recovered, and there is no way of knowing how useful it may have been. We do know that human beings and many of their industries depend on plant and animal products. About 50% of all pharmaceuticals have a natural component as an active ingredient, yet less than one percent of the world's species have been chemically analyzed and tested. Many invertebrates and plants contain undescribed and highly functional compounds. Limnanthes floccosa subsp. grandiflora, or wooly meadow-foam, a rare plant that grows in southwest Oregon, has been recently found to produce a hybrid with the more common member of the genus, Limnanthes alba. This hybrid grows well in the poorly drained soils of the Willamette Valley and produces a valuable oil used for soaps, plastic and rubber production. In addition, the new hybrid meadow-foam does not require the field burning necessary for other crops. This species, and many other Oregon natives, will be lost without intervention. The purpose of this book is to provide land managers, owners and interested parties with a list of those species in Oregon which are in greatest jeopardy. Title: Rare, Threatened and Endangered Plants and Animals of Oregon Author: Kagan, James S., Vrilakas, Sue, Gaines, Eleanor P., Alton, Cliff, Popper, Ken, Stern, Mark A., Scheuering, Eric, Christy, John A., Finnerty, Mary, Hak, Jon, Tovar, Anthony A., Murray, Michael, Tobalske, Claudine, Oregon Natural Heritage Program Year: 2001 Extinction is a natural process. Today, however, plant and animal species are disappearing world-wide at an accelerated pace. Based on current trends, half of the species on earth will be extinct within the next 100 years. The major cause of this phenomenon is large-scale destruction of native habitats, which has increased since European settlement began in the mid 1800's - in Oregon and throughout the New World. Once lost, a species can never be recovered, and there is no way of knowing how useful it may have been. We do know that human beings and many of their industries depend on plant and animal products. About 50% of all pharmaceuticals have a natural component as an active ingredient, yet less than one percent of the world's species have been chemically analyzed and tested. Many invertebrates and plants contain undescribed and highly functional compounds. Limnanthes floccosa subsp. grandiflora, or wooly meadow-foam, a rare plant that grows in southwest Oregon, has been recently found to produce a hybrid with the more common member of the genus, Limnanthes alba. This hybrid grows well in the poorly drained soils of the Willamette Valley and produces a valuable oil used for soaps, plastic and rubber production. In addition, the new hybrid meadow-foam does not require the field burning necessary for other crops. This species, and many other Oregon natives, will be lost without intervention. The purpose of this book is to provide land managers, owners and interested parties with a list of those species in Oregon which are in greatest jeopardy. Close

• 27. [Article] Breeding success and nest site characteristics of the western bluebird on Parrett Mountain

  The lack of suitable nest sites may be a limiting factor for Western Bluebird populations inhabiting the upper Willamette Valley. Nest box trails have been established on the hills surrounding the Portland ...

  Citation × Citation Citation Abstract Copy Title: Breeding success and nest site characteristics of the western bluebird on Parrett Mountain Author: Sims, Marcia Diane Year: 1983 The lack of suitable nest sites may be a limiting factor for Western Bluebird populations inhabiting the upper Willamette Valley. Nest box trails have been established on the hills surrounding the Portland metropolitan area. Since their placement, approximately 25% of the boxes available have been used by Western Bluebirds as nest cavities. This study was undertaken to identify factors which might determine the selection of a nest box by Western Bluebirds and the subsequent nest success or failure. The breeding biology of Western Bluebirds using the nest box trail located on Parrett Mountain, Oregon in 1979 was investigated. Breeding season, mean clutch size, average incubation and nestling periods, and level of nest success were determined. Nest box dimensions, placement, and surrounding habitat features were quantified. Potentially important nest site characteristics were examined and tested for association with Western Bluebird nest box use and reproductive success. Western Bluebird nest box selection was random with regard to all of the characteristics studied except Solar Index and Nest Box Density. No correlation was seen between nest box characteristics and bluebird nest success. Title: Breeding success and nest site characteristics of the western bluebird on Parrett Mountain Author: Sims, Marcia Diane Year: 1983 The lack of suitable nest sites may be a limiting factor for Western Bluebird populations inhabiting the upper Willamette Valley. Nest box trails have been established on the hills surrounding the Portland metropolitan area. Since their placement, approximately 25% of the boxes available have been used by Western Bluebirds as nest cavities. This study was undertaken to identify factors which might determine the selection of a nest box by Western Bluebirds and the subsequent nest success or failure. The breeding biology of Western Bluebirds using the nest box trail located on Parrett Mountain, Oregon in 1979 was investigated. Breeding season, mean clutch size, average incubation and nestling periods, and level of nest success were determined. Nest box dimensions, placement, and surrounding habitat features were quantified. Potentially important nest site characteristics were examined and tested for association with Western Bluebird nest box use and reproductive success. Western Bluebird nest box selection was random with regard to all of the characteristics studied except Solar Index and Nest Box Density. No correlation was seen between nest box characteristics and bluebird nest success. Close

• 28. [Article] Transcriptomic Regulation of Alternative Phenotypic Trajectories in Embryos of the Annual Killifish <i>Austrofundulus limnaeus</i>

  The Annual Killifish, Austrofundulus limnaeus, survives the seasonal drying of their pond habitat in the form of embryos entering diapause midway through development. The diapause trajectory is one of ...

  Citation × Citation Citation Abstract Copy Title: Transcriptomic Regulation of Alternative Phenotypic Trajectories in Embryos of the Annual Killifish <i>Austrofundulus limnaeus</i> Author: Romney, Amie Lynn Thomas Year: 2017 The Annual Killifish, Austrofundulus limnaeus, survives the seasonal drying of their pond habitat in the form of embryos entering diapause midway through development. The diapause trajectory is one of two developmental phenotypes. Alternatively, individuals can "escape" entry into diapause and develop continuously until hatching. The alternative phenotypes of A. limnaeus are a form of developmental plasticity that provides this species with a physiological adaption for surviving stressful environments. The developmental trajectory of an embryo is not distinguishable morphologically upon fertilization and phenotype is believed to be influenced by maternal provisioning within the egg based on observations of offspring phenotype production. However, incubation temperature may override any such maternal pattern suggesting an environmental influence on the regulation of developmental trajectory. We hypothesize that maternally packaged gene products coordinate the cellular events prior to the maternal-to-zygotic transition (MTZ) that determine developmental trajectory in embryos of A. limnaeus. In addition, we propose that environmentally responsive gene expression after the MTZ can sustain or override any such maternal provisioning. Using high-throughput RNA-sequencing, we have generated transcriptomic profiles of protein-coding messenger RNA and noncoding RNA during development in A. limnaeus. Embryos destined for either the diapause or escape phenotypes display unique expression profiles immediately upon fertilization that support hormone synthesis, well before the stage when phenotypes are morphologically distinct. At stages when the trajectories diverge from one another, differential expression of the vitamin D receptor signaling pathway suggests that vitamin D signaling may be a key regulator of developmental phenotype in this species. These data provide a critical link between maternal and environmental influences on the genetic regulation of phenotypic plasticity. These results will not only impact our understanding of the genetic mechanisms that regulate entrance into diapause, but also provide insight into the epigenetic regulation of gene expression and development. Uncovering genetic mechanisms in a system exhibiting alternative developmental trajectories will elucidate the role of maternal packaging in regulating developmental decisions, and in sustaining metabolic depression during diapause. Title: Transcriptomic Regulation of Alternative Phenotypic Trajectories in Embryos of the Annual Killifish <i>Austrofundulus limnaeus</i> Author: Romney, Amie Lynn Thomas Year: 2017 The Annual Killifish, Austrofundulus limnaeus, survives the seasonal drying of their pond habitat in the form of embryos entering diapause midway through development. The diapause trajectory is one of two developmental phenotypes. Alternatively, individuals can "escape" entry into diapause and develop continuously until hatching. The alternative phenotypes of A. limnaeus are a form of developmental plasticity that provides this species with a physiological adaption for surviving stressful environments. The developmental trajectory of an embryo is not distinguishable morphologically upon fertilization and phenotype is believed to be influenced by maternal provisioning within the egg based on observations of offspring phenotype production. However, incubation temperature may override any such maternal pattern suggesting an environmental influence on the regulation of developmental trajectory. We hypothesize that maternally packaged gene products coordinate the cellular events prior to the maternal-to-zygotic transition (MTZ) that determine developmental trajectory in embryos of A. limnaeus. In addition, we propose that environmentally responsive gene expression after the MTZ can sustain or override any such maternal provisioning. Using high-throughput RNA-sequencing, we have generated transcriptomic profiles of protein-coding messenger RNA and noncoding RNA during development in A. limnaeus. Embryos destined for either the diapause or escape phenotypes display unique expression profiles immediately upon fertilization that support hormone synthesis, well before the stage when phenotypes are morphologically distinct. At stages when the trajectories diverge from one another, differential expression of the vitamin D receptor signaling pathway suggests that vitamin D signaling may be a key regulator of developmental phenotype in this species. These data provide a critical link between maternal and environmental influences on the genetic regulation of phenotypic plasticity. These results will not only impact our understanding of the genetic mechanisms that regulate entrance into diapause, but also provide insight into the epigenetic regulation of gene expression and development. Uncovering genetic mechanisms in a system exhibiting alternative developmental trajectories will elucidate the role of maternal packaging in regulating developmental decisions, and in sustaining metabolic depression during diapause. Close

• 29. [Article] A Survey of Small Mammals on Islands in the Columbia and Willamette Rivers

  A survey of small mammals on eight islands in the Columbia and Willamette Rivers near Portland, Oregon was conducted in 1974. The islands were Govermnent , Sand, Lemon, McGuire and Sandy Islands in the ...

  Citation × Citation Citation Abstract Copy Title: A Survey of Small Mammals on Islands in the Columbia and Willamette Rivers Author: Kirk, Gayle Year: 1976 A survey of small mammals on eight islands in the Columbia and Willamette Rivers near Portland, Oregon was conducted in 1974. The islands were Govermnent , Sand, Lemon, McGuire and Sandy Islands in the Columbia River and East, Ross and Hardtack Islands in the Willamette River. The objectives of the study were to ascertain and compare the kinds, distribution and relative densitites of small mammals . A variety of traps was used to capture the animals including Museum Special Rodent Traps , back- break mouse traps, scissor and guillotine- type stab mole traps , Sherman traps , modified Young traps and pitfalls . Most traps were set in linear transects . Trapping was conducted with the objective of sampling the major habitats on each island. Observations of scats, tracks , burrows and dead animals were also noted. One species of small marmnal , Sorex vargrans , was found on all eight islands . Microtus was found on five islands and Peromyscus maniculatus on four islands . Two islands yielded Scapanus townsendii. Glaucomvs sabrinus was found on only one island. I hoped that evidence would be found to prove or disprove that current theories of island biogeography would apply to river islands. However, data in this study were inadequate to allow calculation of precise indices of population densities . Therefore, I was unable to determine if theories of island biogeography do apply to these river islands. Title: A Survey of Small Mammals on Islands in the Columbia and Willamette Rivers Author: Kirk, Gayle Year: 1976 A survey of small mammals on eight islands in the Columbia and Willamette Rivers near Portland, Oregon was conducted in 1974. The islands were Govermnent , Sand, Lemon, McGuire and Sandy Islands in the Columbia River and East, Ross and Hardtack Islands in the Willamette River. The objectives of the study were to ascertain and compare the kinds, distribution and relative densitites of small mammals . A variety of traps was used to capture the animals including Museum Special Rodent Traps , back- break mouse traps, scissor and guillotine- type stab mole traps , Sherman traps , modified Young traps and pitfalls . Most traps were set in linear transects . Trapping was conducted with the objective of sampling the major habitats on each island. Observations of scats, tracks , burrows and dead animals were also noted. One species of small marmnal , Sorex vargrans , was found on all eight islands . Microtus was found on five islands and Peromyscus maniculatus on four islands . Two islands yielded Scapanus townsendii. Glaucomvs sabrinus was found on only one island. I hoped that evidence would be found to prove or disprove that current theories of island biogeography would apply to river islands. However, data in this study were inadequate to allow calculation of precise indices of population densities . Therefore, I was unable to determine if theories of island biogeography do apply to these river islands. Close

• 30. [Article] Predation Avoidance Response Behaviors, Oviposition and Distribution of the Intertidal Gastropod Lirularia succincta

  xiii, 141 p. : ill. (some col.)

  Citation × Citation Citation Abstract Copy Title: Predation Avoidance Response Behaviors, Oviposition and Distribution of the Intertidal Gastropod Lirularia succincta Author: McNeill, Myndee Year: 2011 xiii, 141 p. : ill. (some col.) Title: Predation Avoidance Response Behaviors, Oviposition and Distribution of the Intertidal Gastropod Lirularia succincta Author: McNeill, Myndee Year: 2011 xiii, 141 p. : ill. (some col.) Close