Browsing Biology by Title
Now showing items 160-179 of 228
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Prevalence and evolution of core photosystem II genes in marine cyanobacterial viruses and their hosts
(2006-08)Cyanophages ( cyanobacterial viruses) are important agents of horizontal gene transfer among marine cyanobacteria, the numerically dominant photosynthetic organisms in the oceans. Some cyanophage genomes carry and express ... -
Prey Exchange Rates and the Impact of Predators on Prey Populations in Streams
(1990)We present four lines of evidence that the magnitude of prey exchange (=immigration/emigration) among substrate patches has an overwhelming influence on the perceived effects of predators on prey populations. (1) An extensive ... -
Primiparous and multiparous females differ in mammary gland alveolar development: implications for milk production
(2012-08)Mammary gland capacity is influenced by the number of secretory cells in the gland, the activity of those cells and the size and arrangement of the alveoli that they form. Although reproductive experience has been shown ... -
Procedural effects of prey tethering experiments: Predation of juvenile scallops by crabs and sea stars
(1994)This study examines the effects of an experimental tethering procedure often used in field predation experiments. In laboratory experiments, juvenile sea scallops Placopecten magellanicus, either free or tethered, were ... -
Proceedings of the Bioregional Farmer/Scientist Workshop in Organic Agriculture (Maine & Maritime Provinces), 1988•
(Organic Crop Improvement Association of New Brunswick & Dalhousie University, 1991-06-15)Proceedings of a workshop -
Quantitative fatty acid signature analysis: A new method of estimating predator diets
(2004-05)Accurate estimates of the diets of predators are required in many areas of ecology, but for many species current methods are imprecise, limited to the last meal, and often biased. The diversity of fatty acids and their ... -
Rapid Global Expansion of Invertebrate Fisheries: Trends, Drivers, and Ecosystem Effects
(2011-03)Background: Worldwide, finfish fisheries are receiving increasing assessment and regulation, slowly leading to more sustainable exploitation and rebuilding. In their wake, invertebrate fisheries are rapidly expanding with ... -
Reciprocal Subsidies and Food Web Pathways Leading to Chum Salmon Fry in a Temperate Marine-Terrestrial Ecotone
(2010-04)Stable isotope analysis was used to determine the relative proportions of terrestrial and marine subsidies of carbon to invertebrates along a tidal gradient (low-intertidal, mid-intertidal, high-intertidal, supralittoral) ... -
Recurrent outbreaks of disease in sea urchins Strongylocentrotus droebachiensis in Nova Scotia: Evidence for a link with large-scale meteorologic and oceanographic events
(1997-06)Recurrent outbreaks of a disease (paramoebiasis, caused by a marine amoeba Paramoeba invadens) result in mass mortalities of sea urchins Strongylocentrotus droebachiensis in the rocky subtidal zone of the Atlantic coast ... -
Reduced Retinal Function in the Absence of Na(v)1.6
(2012-02)Background: Mice with a function-blocking mutation in the Scn8a gene that encodes Na(v)1.6, a voltage-gated sodium channel (VGSC) isoform normally found in several types of retinal neurons, have previously been found to ... -
Reducing risks from E. coli 0157 on the organic farm
(Canadian Centre for Sustainable Agriculture, Saskatoon, Saskatchewan., 2001)E.coli 0157 is a bacterial pathogen of the human intestinal tract which is carried in certain species of livestock and wildlife without ill effect. Such organisms are termed zoonotics. Various types of Campylobacter and ... -
Reflections on the failure of traditional fisheries management
(2017-01)A traditional fisheries management or fish stock assessment takes a Lamarckian-like instructive view of fisheries science that involves an inductive monism. Its invalid inductive arguments have no problem solving capacity ... -
Reflections on the failure of traditional fisheries management
(2016-06-03)A traditional fisheries management or fish stock assessment takes a Lamarckian-like instructive view of fisheries science. Its invalid inductive arguments have no problem solving capacity and are responsible for the collapse ... -
Refuge dynamics and metapopulation dynamics: An experimental test
(1996-03)Red scale, an insect pest of citrus, is under control by the parasitoid Aphytis melinus in many areas, and in our study area the interaction appears dynamically stable. The bark on the interior branches and trunk of trees ... -
A Refuge for Red Scale the Role of Size-Selectivity by a Parasitoid Wasp
(1989)The presence of a physical refuge (an area where mortality due to parasitism is very low) has been demonstrated for California red scale, a pest of citrus. Density of red scale is very high, and parasitism by the principal ... -
A Refuge for Red Scale Under Control by Aphytis - Structural Aspects
(1989-12)No abstract available. -
Regeneration of Forest and Barrens after the Spryfield Fire
(2010-09-02)This set of annotated photos illustrates the regeneration of vegetation over 16 months after an intense fire that swept through forest and barrens in the vicinity of Spryfield, Nova Scotia on April 30/May 1 of 2009. The ... -
Regional-scale effects of eutrophication on ecosystem structure and services of seagrass beds
(2012-09)Using large-scale field surveys across 12 estuaries in two provinces in Atlantic Canada, we analyzed changes in phytoplankton and benthic macroalgal communities as well as the canopy structure of eelgrass beds and quantified ... -
Regulation of an Insect Population Under Biological-Control
(1995-01)California red scale is suppressed to very low densities by the parasitoid Aphytis melinus. The system also appears stable. We report on an experimental test of the hypothesis that stability is caused by a refuge for scale. ...