Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 19 of 19
Full-Text Articles in Life Sciences
The Oxidative Costs Of Territory Quality And Offspring Provisioning, S. Guindre-Parker, S. Baldo, H. G. Gilchrist, C. A. Macdonald, C. M. Harris, O. P. Love
The Oxidative Costs Of Territory Quality And Offspring Provisioning, S. Guindre-Parker, S. Baldo, H. G. Gilchrist, C. A. Macdonald, C. M. Harris, O. P. Love
Integrative Biology Publications
The costs of reproduction are an important constraint that shapes the evolution of life histories, yet our understanding of the proximate mechanism(s) leading to such life-history trade-offs is not well understood. Oxidative stress is a strong candidate measure thought to mediate the costs of reproduction, yet empirical evidence supporting that increased reproductive investment leads to oxidative stress is equivocal. We investigated whether territory quality and offspring provisioning increase oxidative stress in male snow buntings (Plectrophenax nivalis) using a repeated sampling design. We show that arrival oxidative stress is not a constraint on territory quality or the number of offspring fledged. …
Variable Δ15n Diet-Tissue Discrimination Factors Among Sharks: Implications For Trophic Position, Diet And Food Web Models, Jill A. Olin, Nigel E. Hussey, Alice Grgicak-Mannion, Mark W. Fritts, Sabine T. Wintner, Aaron T. Fisk
Variable Δ15n Diet-Tissue Discrimination Factors Among Sharks: Implications For Trophic Position, Diet And Food Web Models, Jill A. Olin, Nigel E. Hussey, Alice Grgicak-Mannion, Mark W. Fritts, Sabine T. Wintner, Aaron T. Fisk
Great Lakes Institute for Environmental Research Publications
The application of stable isotopes to characterize the complexities of a species foraging behavior and trophic relationships is dependent on assumptions of δ15N diet-tissue discrimination factors (∆15N). As ∆15N values have been experimentally shown to vary amongst consumers, tissues and diet composition, resolving appropriate speciesspecific ∆15N values can be complex. Given the logistical and ethical challenges of controlled feeding experiments for determining ∆ 15N values for large and/or endangered species, our objective was to conduct an assessment of a range of reported ∆ 15N values that can hypothetically serve as surrogates for describing the predator-prey relationships of four shark species …
Diatom Assemblages Promote Ice Formation In Large Lakes, N. A. D'Souza, Y. Kawarasaki, J. D. Gantz, R. E. Lee, B. F.N. Beall, Y. M. Shtarkman, Z. A. Koçer, S. O. Rogers, H. Wildschutte, G. S. Bullerjahn, R. M.L. Mckay
Diatom Assemblages Promote Ice Formation In Large Lakes, N. A. D'Souza, Y. Kawarasaki, J. D. Gantz, R. E. Lee, B. F.N. Beall, Y. M. Shtarkman, Z. A. Koçer, S. O. Rogers, H. Wildschutte, G. S. Bullerjahn, R. M.L. Mckay
Great Lakes Institute for Environmental Research Publications
We present evidence for the directed formation of ice by planktonic communities dominated by filamentous diatoms sampled from the ice-covered Laurentian Great Lakes. We hypothesize that ice formation promotes attachment of these non-motile phytoplankton to overlying ice, thereby maintaining a favorable position for the diatoms in the photic zone. However, it is unclear whether the diatoms themselves are responsible for ice nucleation. Scanning electron microscopy revealed associations of bacterial epiphytes with the dominant diatoms of the phytoplankton assemblage, and bacteria isolated from the phytoplankton showed elevated temperatures of crystallization (T c) as high as -3 °C. Ice nucleation-active bacteria were …
Baseline Corticosterone In Wintering Marine Birds: Methodological Considerations And Ecological Patterns, E. C. Palm, D. Esler, E. M. Anderson, T. D. Williams, O. P. Love, M. T. Wilson
Baseline Corticosterone In Wintering Marine Birds: Methodological Considerations And Ecological Patterns, E. C. Palm, D. Esler, E. M. Anderson, T. D. Williams, O. P. Love, M. T. Wilson
Integrative Biology Publications
Previous studies have related levels of plasma corticosterone (CORT) of seabirds to variation in foraging conditions during the breeding period, but it is unclear whether similar relationships between foraging conditions and baseline CORT exist during other life stages. We validated methods for identifying baseline CORT of lethally sampled birds and assessed variation in baseline CORT relative to winter habitat conditions. We collected free-living white-winged scoters (Melanitta fusca) at four wintering sites during December and February. We found increasing CORT values beyond 3 min after time since flush (the duration between initial flush and death), presumably reflecting acute stress responses. Our …
Condition-Dependent Auditory Processing In The Round Goby (Neogobius Melanostomus): Links To Sex, Reproductive Condition And Female Estrogen Levels, Jeffrey N. Zeyl, Oliver P. Love, Dennis M. Higgs
Condition-Dependent Auditory Processing In The Round Goby (Neogobius Melanostomus): Links To Sex, Reproductive Condition And Female Estrogen Levels, Jeffrey N. Zeyl, Oliver P. Love, Dennis M. Higgs
Integrative Biology Publications
Neural responses to sensory stimuli often differ between sexes, vary seasonally, and can be regulated by endocrine activity, but the ecological and physiological mechanisms driving such patterns are not well understood. The current study examined how auditory function in the round goby (Neogobius melanostomus), a vocal teleost, co-varied with sex, reproductive condition and female plasma 17β-estradiol level. Auditory evoked potentials were collected in response to tone pips (100-600 Hz) and a natural round goby pulse vocalization. Additionally, saccule hair cell densities were compared across reproductive groups. Auditory threshold was evaluated in terms of pressure and particle acceleration, and response amplitude …
The Neuroanatomical Organization Of Projection Neurons Associated With Different Olfactory Bulb Pathways In The Sea Lamprey, Petromyzon Marinus, Warren W. Green, Alfred Basilious, Réjean Dubuc, Barbara S. Zielinski
The Neuroanatomical Organization Of Projection Neurons Associated With Different Olfactory Bulb Pathways In The Sea Lamprey, Petromyzon Marinus, Warren W. Green, Alfred Basilious, Réjean Dubuc, Barbara S. Zielinski
Biological Sciences Publications
Although there is abundant evidence for segregated processing in the olfactory system across vertebrate taxa, the spatial relationship between the second order projection neurons (PNs) of olfactory subsystems connecting sensory input to higher brain structures is less clear. In the sea lamprey, there is tight coupling between olfaction and locomotion via PNs extending to the posterior tuberculum from the medial region of the olfactory bulb. This medial region receives peripheral input predominantly from the accessory olfactory organ. However, the axons from olfactory sensory neurons residing in the main olfactory epithelium extend to non-medial regions of the olfactory bulb, and the …
An Activated Form Of Ufo Alters Leaf Development And Produces Ectopic Floral And Inflorescence Meristems, Eddy Risseeuw, Prakash Venglat, Daoquan Xiang, Kristina Komendant, Tim Daskalchuk, Vivijan Babic, William L. Crosby, Raju Datla
An Activated Form Of Ufo Alters Leaf Development And Produces Ectopic Floral And Inflorescence Meristems, Eddy Risseeuw, Prakash Venglat, Daoquan Xiang, Kristina Komendant, Tim Daskalchuk, Vivijan Babic, William L. Crosby, Raju Datla
Biological Sciences Publications
Plants are unique in their ability to continuously produce new meristems and organ primordia. In Arabidopsis, the transcription factor LEAFY (LFY) functions as a master regulator of a gene network that is important for floral meristem and organ specification. UNUSUAL FLORAL ORGANS (UFO) is a co-activator of LEAFY and is required for proper activation of APETALA3 in the floral meristem during the specification of stamens and petals. The ufo mutants display defects in other parts of the flower and the inflorescence, suggestive of additional roles. Here we show that the normal determinacy of the developing Arabidopsis leaves is affected by …
A Comparison Of The Molecular Organization Of Genomic Regions Associated With Resistance To Common Bacterial Blight In Two Phaseolus Vulgaris Genotypes, Gregory Perry, Claudia Dinatale, Weilong Xie, Alireza Navabi, Yarmilla Reinprecht, William L. Crosby, Kangfu Yu, Chun Shi, Peter K. Pauls
A Comparison Of The Molecular Organization Of Genomic Regions Associated With Resistance To Common Bacterial Blight In Two Phaseolus Vulgaris Genotypes, Gregory Perry, Claudia Dinatale, Weilong Xie, Alireza Navabi, Yarmilla Reinprecht, William L. Crosby, Kangfu Yu, Chun Shi, Peter K. Pauls
Biological Sciences Publications
Resistance to common bacterial blight, caused by Xanthomonas axonopodis pv. phaseoli, in Phaseolus vulgaris is conditioned by several loci on different chromosomes. Previous studies with OAC-Rex, a CBB-resistant, white bean variety of Mesoamerican origin, identified two resistance loci associated with the molecular markers Pv-CTT001 and SU91, on chromosome 4 and 8, respectively. Resistance to CBB is assumed to be derived from an interspecific cross with Phaseolus acutifolius in the pedigree of OAC-Rex. Our current whole genome sequencing effort with OAC-Rex provided the opportunity to compare its genome in the regions associated with CBB resistance with the v1.0 release of the …
Bacteria Mediate Oviposition By The Black Soldier Fly, Hermetia Illucens (L.), (Diptera: Stratiomyidae), Longyu Zheng, Tawni L. Crippen, Leslie Holmes, Baneshwar Singh, Meaghan L. Pimsler, M. Eric Benbow, Aaron M. Tarone, Scot Dowd, Ziniu Yu, Sherah L. Vanlaerhoven, Thomas K. Wood, Jeffery K. Tomberlin
Bacteria Mediate Oviposition By The Black Soldier Fly, Hermetia Illucens (L.), (Diptera: Stratiomyidae), Longyu Zheng, Tawni L. Crippen, Leslie Holmes, Baneshwar Singh, Meaghan L. Pimsler, M. Eric Benbow, Aaron M. Tarone, Scot Dowd, Ziniu Yu, Sherah L. Vanlaerhoven, Thomas K. Wood, Jeffery K. Tomberlin
Biological Sciences Publications
Article
Baseline Corticosterone In Wintering Marine Birds: Methodological Considerations And Ecological Patterns, E. C. Palm, D. Esler, E. M. Anderson, Tony D. Williams, O. P. Love, M. T. Wilson
Baseline Corticosterone In Wintering Marine Birds: Methodological Considerations And Ecological Patterns, E. C. Palm, D. Esler, E. M. Anderson, Tony D. Williams, O. P. Love, M. T. Wilson
Biological Sciences Publications
Previous studies have related levels of plasma corticosterone (CORT) of seabirds to variation in foraging conditions during the breeding period, but it is unclear whether similar relationships between foraging conditions and baseline CORT exist during other life stages. We validated methods for identifying baseline CORT of lethally sampled birds and assessed variation in baseline CORT relative to winter habitat conditions. We collected free-living white-winged scoters (Melanitta fusca) at four wintering sites during December and February. We found increasing CORT values beyond 3 min after time since flush (the duration between initial flush and death), presumably reflecting acute stress responses. Our …
Food Web Structure In Oil Sands Reclaimed Wetlands, K. E. Kovalenko, Jan J.H. Ciborowski, C. Daly, D. G. Dixon, A. J. Farwell, A. L. Foote, K. R. Frederick, J. M. Costa, K. Kennedy, K. Liber, M. C. Roy
Food Web Structure In Oil Sands Reclaimed Wetlands, K. E. Kovalenko, Jan J.H. Ciborowski, C. Daly, D. G. Dixon, A. J. Farwell, A. L. Foote, K. R. Frederick, J. M. Costa, K. Kennedy, K. Liber, M. C. Roy
Biological Sciences Publications
No abstract provided.
Genetic Diversity In Introduced Golden Mussel Populations Corresponds To Vector Activity, Sara Ghabooli, Aibin Zhan, Paula Sardina, Esteban Paolucci, Francisco Sylvester, Pablo V. Perepelizin, Elizabeta Briski, Melania E. Cristescu, Hugh J. Macisaac
Genetic Diversity In Introduced Golden Mussel Populations Corresponds To Vector Activity, Sara Ghabooli, Aibin Zhan, Paula Sardina, Esteban Paolucci, Francisco Sylvester, Pablo V. Perepelizin, Elizabeta Briski, Melania E. Cristescu, Hugh J. Macisaac
Biological Sciences Publications
We explored possible links between vector activity and genetic diversity in introduced populations of Limnoperna fortunei by characterizing the genetic structure in native and introduced ranges in Asia and South America. We surveyed 24 populations: ten in Asia and 14 in South America using the mitochondrial cytochrome c oxidase subunit I (COI) gene, as well as eight polymorphic microsatellite markers. We performed population genetics and phylogenetic analyses to investigate population genetic structure across native and introduced regions. Introduced populations in Asia exhibit higher genetic diversity (HE = 0.667–0.746) than those in South America (HE = 0.519–0.575), suggesting higher introduction effort …
Invasion Pathway Of The Ctenophore Mnemiopsis Leidyi In The Mediterranean Sea, Sara Ghabooli, Tamara A. Shiganova, Elizabeta Briski, Stefano Piraino, Veronica Fuentes, Delphine Thibault-Botha, Dror L. Angel, Melania E. Cristescu, Hugh J. Macisaac
Invasion Pathway Of The Ctenophore Mnemiopsis Leidyi In The Mediterranean Sea, Sara Ghabooli, Tamara A. Shiganova, Elizabeta Briski, Stefano Piraino, Veronica Fuentes, Delphine Thibault-Botha, Dror L. Angel, Melania E. Cristescu, Hugh J. Macisaac
Biological Sciences Publications
Gelatinous zooplankton outbreaks have increased globally owing to a number of human-mediated factors, including food web alterations and species introductions. The invasive ctenophore Mnemiopsis leidyi entered the Black Sea in the early 1980s. The invasion was followed by the Azov, Caspian, Baltic and North Seas, and, most recently, the Mediterranean Sea. Previous studies identified two distinct invasion pathways of M. leidyi from its native range in the western Atlantic Ocean to Eurasia. However, the source of newly established populations in the Mediterranean Sea remains unclear. Here we build upon our previous study and investigate sequence variation in both mitochondrial (Cytochrome …
Separation Strategies For Invertebrate Dormant Stages Contained In Sediment, Elizabeta Briski, Sarah A. A. Bailey, Hugh J. Macisaac
Separation Strategies For Invertebrate Dormant Stages Contained In Sediment, Elizabeta Briski, Sarah A. A. Bailey, Hugh J. Macisaac
Biological Sciences Publications
No abstract provided.
The Circadian Clock Gates The Intestinal Stem Cell Regenerative State, Phillip Karpowicz, Yong Zhang, John B. Hogenesch, Patrick Emery, Norbert Perrimon
The Circadian Clock Gates The Intestinal Stem Cell Regenerative State, Phillip Karpowicz, Yong Zhang, John B. Hogenesch, Patrick Emery, Norbert Perrimon
Biological Sciences Publications
The intestine has evolved under constant environmental stresses, because an animal may ingest harmful pathogens or chemicals at any time during its lifespan. Following damage, intestinal stem cells (ISCs) regenerate the intestine by proliferating to replace dying cells. ISCs from diverse animals are remarkably similar, and the Wnt, Notch, and Hippo signaling pathways, important regulators of mammalian ISCs, are conserved from flies to humans. Unexpectedly, we identified the transcription factor period, a component of the circadian clock, to be critical for regeneration, which itself follows a circadian rhythm. We discovered hundreds of transcripts that are regulated by the clock during …
The Relationship Between Nucleolar Organizer Size And Growth In Chironomus Riparius Larvae (Diptera:Chironomidae), Joshua. P. Martin, Carla M. Wytrykush, Jan J.H. Ciborowski
The Relationship Between Nucleolar Organizer Size And Growth In Chironomus Riparius Larvae (Diptera:Chironomidae), Joshua. P. Martin, Carla M. Wytrykush, Jan J.H. Ciborowski
Biological Sciences Publications
No abstract provided.
Variable Δ15n Diet-Tissue Discrimination Factors Among Sharks: Implications For Trophic Position, Diet And Food Web Models, J. A. Olin, N. E. Hussey, Grgicak-Mannion, A. Grgicak-Mannion, A., M. W. Fritts, S. P. Wintner, A. T. Fisk
Variable Δ15n Diet-Tissue Discrimination Factors Among Sharks: Implications For Trophic Position, Diet And Food Web Models, J. A. Olin, N. E. Hussey, Grgicak-Mannion, A. Grgicak-Mannion, A., M. W. Fritts, S. P. Wintner, A. T. Fisk
Biological Sciences Publications
No abstract provided.
Environmental Associations With Gene Transcription In Babine Lake Rainbow Trout: Evidence For Local Adaptation., K. W. Wellband, Daniel D. Heath
Environmental Associations With Gene Transcription In Babine Lake Rainbow Trout: Evidence For Local Adaptation., K. W. Wellband, Daniel D. Heath
Great Lakes Institute for Environmental Research Publications
The molecular genetic mechanisms facilitating local adaptation in salmonids continue to be poorly characterized. Gene transcription is a highly regulated step in the expression of a phenotype and it has been shown to respond to selection and thus may be one mechanism that facilitates the development of local adaptation. Advances in molecular genetic tools and an increased understanding of the functional roles of specific genes allow us to test hypotheses concerning the role of variable environments in shaping transcription at known-function candidate loci. To address these hypotheses, wild rainbow trout were collected in their first summer and subjected to metabolic …
Rates And Controls Of Nitrification In A Large Oligotrophic Lake, Gaston E. Small, George S. Bullerjahn, Robert W. Sterner, Benjamin F.N. Beall, Sandra Brovold, Jacques C. Finlay, Robert M.L. Mckay, Maitreyee Mukherjee
Rates And Controls Of Nitrification In A Large Oligotrophic Lake, Gaston E. Small, George S. Bullerjahn, Robert W. Sterner, Benjamin F.N. Beall, Sandra Brovold, Jacques C. Finlay, Robert M.L. Mckay, Maitreyee Mukherjee
Great Lakes Institute for Environmental Research Publications
Recent discoveries have altered prevailing paradigms concerning the conditions under which nitrification takes place and the organisms responsible for nitrification in aquatic ecosystems. In Lake Superior, nitrate (NO-3) concentrations have increased fivefold in the past century. Although previous evidence indicated that most NO-3 is generated by nitrification within the lake, important questions remain concerning the magnitude and controls of nitrification, and which microbial groups are primarily responsible for this process. We measured water-column nitrification rates in the western basin of Lake Superior during five research cruises from November 2009 to March 2011. Using in situ bottle incubations at 10 depths, …