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Full-Text Articles in Biology
Evolutionary And Acclimation-Induced Variation In The Heat-Shock Responses Of Congeneric Marine Snails (Genus Tegula) From Different Thermal Habitats: Implications For Limits Of Thermotolerance And Biogeography, Lars Tomanek, George N. Somero
Evolutionary And Acclimation-Induced Variation In The Heat-Shock Responses Of Congeneric Marine Snails (Genus Tegula) From Different Thermal Habitats: Implications For Limits Of Thermotolerance And Biogeography, Lars Tomanek, George N. Somero
Biological Sciences
Heat stress sufficient to cause cellular damage triggers the heat-shock response, the enhanced expression of a group of molecular chaperones called heat-shock proteins (hsps). We compared the heat-shock responses of four species of marine snails of the genus Tegula that occupy thermal niches differing in absolute temperature and range of temperature. We examined the effects of short-term heat stress and thermal acclimation on the synthesis of hsps of size classes 90, 77, 70 and 38 kDa by measuring incorporation of (35)S-labeled methionine and cysteine into newly synthesized proteins in gill tissue. Temperatures at which enhanced synthesis of hsps first occurred …
The Edaphic Factor And Patterns Of Variation In Lasthenia Californica (Asteraceae), Nishanta Rajakaruna, Bruce A. Bohm
The Edaphic Factor And Patterns Of Variation In Lasthenia Californica (Asteraceae), Nishanta Rajakaruna, Bruce A. Bohm
Biological Sciences
Transectional studies of Lasthenia californica in the Jasper Ridge Biological Preserve (Stanford University) have documented the existence of two races (A and C) based upon flavonoid chemistry, achene morphology, allozymes, and flowering time differences. The two races coexist on a serpentine outcrop and have maintained a sharply defined pattern of distribution for a period of at least 15 yr. The present study has revealed significant differences in the physical and chemical features of the soils harboring the two races. Soils at the lower ends of the transects, where race A plants grow, have higher pH, cation exchange capacity, relative water …
Optical Monitoring And Forecasting Systems For Harmful Algal Blooms: Possibility Or Pipe Dream?, Mark A. Moline, Oscar Schofield, Joe Grzymski, Paul W. Bissett, Gary J. Kirkpatrick, David F. Millie, Collin S. Roesler
Optical Monitoring And Forecasting Systems For Harmful Algal Blooms: Possibility Or Pipe Dream?, Mark A. Moline, Oscar Schofield, Joe Grzymski, Paul W. Bissett, Gary J. Kirkpatrick, David F. Millie, Collin S. Roesler
Biological Sciences
Monitoring programs for harmful algal blooms (HABs) are currently reactive and provide little or no means for advance warning. Given this, the development of algal forecasting systems would be of great use because they could guide traditional monitoring programs and provide a proactive means for responding to HABs. Forecasting systems will require near real-time observational capabilities and hydrodynamic/biological models designed to run in the forecast mode. These observational networks must detect and forecast over ecologically relevant spatial/ temporal scales. One solution is to incorporate a multiplatform optical approach utilizing remote sensing and in situ moored technologies. Recent advances in instrumentation …
Makaira Sp., Cf. M. Nigricans Lacépède, 1802 (Teleostei: Perciformes: Istiophoridae) From The Late Miocene, Panama, And Its Probable Use Of The Panama Seaway, Harry L. Fierstine
Makaira Sp., Cf. M. Nigricans Lacépède, 1802 (Teleostei: Perciformes: Istiophoridae) From The Late Miocene, Panama, And Its Probable Use Of The Panama Seaway, Harry L. Fierstine
Biological Sciences
A nearly complete rostrum (USNM 358534) similar in morphology to the extant bluc marlin, Makaira nigricans Lacepede 1802, is identified from the GaUln Formation (late Miocene, Panama). Identification is based on comparison with a large series of Recent istiophorid species and with fossil species of the genus Makaira. The Gatlin specimen and additional examples from other fossil vertebrates provide evidence that the ancient Panama Seaway probably was a travel route between the Atlantic and Indo-Pacific for large marine vertebrates during the middle Miocene to earliest Pliocene. This is the first record of an istiophorid billfish from the Gatlin Fonnation and …
Variation And Repeatability Of Calling Behavior In Crickets Subject To A Phonotactic Parasitoid Fly, Gita R. Kolluru
Variation And Repeatability Of Calling Behavior In Crickets Subject To A Phonotactic Parasitoid Fly, Gita R. Kolluru
Biological Sciences
Male Teleogryllus oceanicus (Orthoptera: Gryllidae) produce a conspicuous calling song to attract females. In some populations, the song also attracts the phonotactic parasitoid fly Ormia ochracea (Diptera: Tachinidae). I examined the factors affecting calling song by characterizing the calling behavior of caged crickets from an area where the fly occurs. Calling activity (proportion of time spent calling) was repeatable and a significant predictor of female attraction. However, calling activity in the parasitized population was lower than in an unparasitized Moorea population (Orsak, 1988), suggesting a compromise between high activity to attract females and low activity to avoid flies. Calling activity …
Conservation Implications Of Dietary Dilution From Debris Ingestion: Sublethal Effects In Post-Hatchling Loggerhead Sea Turtles, Shannon J. Mccauley, Karen A. Bjomdal
Conservation Implications Of Dietary Dilution From Debris Ingestion: Sublethal Effects In Post-Hatchling Loggerhead Sea Turtles, Shannon J. Mccauley, Karen A. Bjomdal
Biological Sciences
Ingestion of anthropogenic debris by marine species has been documented extensively; fewer studies have attempted to quantify the sublethal effects caused by debris ingestion. One potential sublethal effect is reduced nutrient gains from diets diluted by consumption of debris. Post-hatchling and juvenile loggerhead sea turtles (Caretta caretta) consume substantial quantities of debris. We evaluated the effects of dietary dilution on voluntary intake in post-hatchling loggerheads to assess their ability to compensate for the presence of inert diluents in their diet by increasing dry mass intakes to maintain nutrient gains. Mean daily intakes of dry mass did not increase …
Diversity Of Microorganisms Isolated From Amber, C. L. Greenblatt, A. Davis, B. G. Clement, Christopher Kitts, T. Cox, Raul J. Cano
Diversity Of Microorganisms Isolated From Amber, C. L. Greenblatt, A. Davis, B. G. Clement, Christopher Kitts, T. Cox, Raul J. Cano
Biological Sciences
Claims that organisms can be cultured from amber, if substantiated, would be significant contributions to our understanding of the evolution, tenacity, and potential spread of life. Three reports on the isolation of organisms from amber have been published. Cano and Borucki recently reported the isolation of Bacillus sphaericus and Lambert et al. have described a new species designated Staphylococcus succinus from 25–40 million year old Dominican amber. These characterized organisms were phylogenetically distant from extant relatives and the Staphylococcus sp. sufficiently far removed from other extant staphylococci to be considered a new species. Here we report the culture of bacteria …
Capillary Density Of Skeletal Muscle: A Contributing Mechanism For Exercise Intolerance In Class Ii–Iii Chronic Heart Failure Independent Of Other Peripheral Alterations, Brian D. Duscha, William E. Kraus, Steven J. Keteyian, Martin J. Sullivan, Howard J. Green, Fred H. Schachat, Anne M. Pippen, Clinton A. Brawner, Jason M. Blank, Brian H. Annex
Capillary Density Of Skeletal Muscle: A Contributing Mechanism For Exercise Intolerance In Class Ii–Iii Chronic Heart Failure Independent Of Other Peripheral Alterations, Brian D. Duscha, William E. Kraus, Steven J. Keteyian, Martin J. Sullivan, Howard J. Green, Fred H. Schachat, Anne M. Pippen, Clinton A. Brawner, Jason M. Blank, Brian H. Annex
Biological Sciences
No abstract provided.
A New Shortbilled Marlin Of The Genus Makaira, From The Yorktown Formation, (Early Pliocene), Eastern North Carolina At Lee Creek Mine, Usa, Harry L. Fierstine
A New Shortbilled Marlin Of The Genus Makaira, From The Yorktown Formation, (Early Pliocene), Eastern North Carolina At Lee Creek Mine, Usa, Harry L. Fierstine
Biological Sciences
An unusually short rostrum from the Yorktown Formation, Early Pliocene, eastern North Carolina at Lee Creek Mine, USA, is described as a new species, Makaira purdyi. The rostrum is morphologically distinct from any Recent or fossil istiophorid in the following combination of characters: (1) fused portion of premaxillae is short and stout with denticlcs covering at least the distal one-half of its dorsal surface; (2) at one-fourth bill length, the cross-section is nearly round (depth/width = 0.95). The new marlin is distinguished from the extant shortbill spearfish, Tetrapturus angustirostris, and any istiophorid with a short rostrum caused by …
Cryptic Luminescence In The Cold-Water Fish Pathogen Vibrio Salmonicida, P. M. Fidopiastis, Henning Sørum, E. G. Ruby
Cryptic Luminescence In The Cold-Water Fish Pathogen Vibrio Salmonicida, P. M. Fidopiastis, Henning Sørum, E. G. Ruby
Biological Sciences
The recent discovery that the fish pathogen Vibrio salmonicida is closely related to the luminous bacteria Vibrio fischeri and Vibrio logei suggested that V. salmonicida might also be capable of bioluminescence. Interestingly, cells of V. salmonicida were found to produce light in culture, but only when exposed to either an aliphatic aldehyde and/or the major V. fischeri autoinducer N-(3-oxo-hexanoyl)-l-homoserine lactone, a transcriptional activator of the luminescence (lux) genes. An extract of spent medium of V. salmonicida that should contain any V. salmonicida acyl-homoserine lactone autoinducer, when added to V. fischeri cells, led to an induction of their …
Ontogenies Of Phototactic Behavior And Metamorphic Competence In Larvae Of Three Species Of Bugula (Bryozoa), Dean E. Wendt, Robert M. Woollacott
Ontogenies Of Phototactic Behavior And Metamorphic Competence In Larvae Of Three Species Of Bugula (Bryozoa), Dean E. Wendt, Robert M. Woollacott
Biological Sciences
The free swimming larvae of many marine invertebrates actively respond to light. Light cues can be used to regulate position in the water column and to facilitate encountering sites suitable for metamorphosis. We examined the ontogeny of larval phototaxis and the ontogeny of metamorphic competency in larvae from three congeneric species of bryozoans. Larvae of Bugula neritina are positively phototactic on emergence from the brood chamber, whereas larvae of B. simplex and B. stolonifera appear initially photoneutral when populations of larvae are examined. Larvae of all three species become photonegative with time. Temporally coincident with this change to negative phototaxis …
Response To Dietary Dilution In An Omnivorous Freshwater Turtle: Implications For Ontogenetic Dietary Shifts, Shannon J. Mccauley, Karen A. Bjorndal
Response To Dietary Dilution In An Omnivorous Freshwater Turtle: Implications For Ontogenetic Dietary Shifts, Shannon J. Mccauley, Karen A. Bjorndal
Biological Sciences
Several species of freshwater turtles in the family Emydidae undergo an ontogenetic dietary shift; as juvenile turtles mature, they change from a primarily carnivorous to a primarily herbivorous diet. It has been hypothesized that this shift results from an unfavorable ratio of gut capacity to metabolic rate that prevents small reptiles from processing adequate volumes of plant material to meet their energetic demands. Effects of dietary dilution on intake were evaluated in two size classes of red-eared sliders (Trachemys scripta elegans) to test whether small reptiles have a lower capacity to compensate for low-quality diets through increased intake …
Determining The Source Of Individuals: Multilocus Genotyping In Nonequilibrium Population Genetics, Neil Davies, Francis X. Villablanca, George K. Roderick
Determining The Source Of Individuals: Multilocus Genotyping In Nonequilibrium Population Genetics, Neil Davies, Francis X. Villablanca, George K. Roderick
Biological Sciences
Recently founded populations represent an enormous challenge for genetic analysis: new populations are often genetically impoverished, making it hard to find sufficiently variable markers, and what little variation is present tends to be ancestral, rendering phylogenetic methods inappropriate. Recently, novel genetic markers and new statistical analyses have made multilocus genotyping an invaluable tool in the fledgling field of nonequilibrium population genetics. Such advances are not of mere academic interest but address questions of great economic, medical and conservation significance.