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Darwin At The Drugstore? Testing The Biological Fitness Of Antibiotic Resistant Bacteria, Alan L. Gillen, Sarah Anderson
Darwin At The Drugstore? Testing The Biological Fitness Of Antibiotic Resistant Bacteria, Alan L. Gillen, Sarah Anderson
Alan L. Gillen
The issue of antibiotic resistance in bacteria is growing. For example, methicillin-resistant Staphylococcus aureus (MRSA) is a leading human pathogen. New strains of MRSA are resistant to methicillin and numerous other antibiotics, placing the patient in significant danger. Indeed, the Centers for Disease Control revealed in 2007 that the number of deaths due to MRSA exceeded that of AIDS in the United States. It is no wonder that antibiotic resistance is one of the most significant and important health care issues. The ability of bacterial pathogens to evade traditional antibiotics is faster than the drug makers’ ability to make new …
Law And Biology: Toward An Integrated Model Of Human Behavior, Owen D. Jones
Law And Biology: Toward An Integrated Model Of Human Behavior, Owen D. Jones
Owen Jones
As first year law students unhappily discover, the meaning of "law" is frustratingly protean, shifting by usage and user. Depending on whom you ask, law is a system of rules, a body of precedents, a legislative enactment, a collection of norms, a process by which social goals are pursued, or some dynamic mixture of these. Law's principal purpose is to define and protect individual rights, to ensure public order, to resolve disputes, to redistribute wealth, to dispense justice, to prevent or compensate for injury, to optimize economic efficiency, or perhaps to do something else. And yet one thing is irreducibly …
On The Nature Of Norms: Biology, Morality, And The Disruption Of Order, Owen D. Jones
On The Nature Of Norms: Biology, Morality, And The Disruption Of Order, Owen D. Jones
Owen Jones
This essay discusses the legal implications of bio-behavioral underpinnings to norms, morality, and economic order. It first discusses the recent book "The Great Disruption: Human Nature and the Reconstitution of Social Order," in which Francis Fukuyama explores the importance of evolved human nature to the reconstruction of social order and a thriving economy. It then addresses the extent to which we can usefully view law-relevant norms as products of evolutionary - as well as economic - processes.
Law And Behavioral Biology, Owen D. Jones, Timothy H. Goldsmith
Law And Behavioral Biology, Owen D. Jones, Timothy H. Goldsmith
Owen Jones
Society uses law to encourage people to behave differently than they would behave in the absence of law. This fundamental purpose makes law highly dependent on sound understandings of the multiple causes of human behavior. The better those understandings, the better law can achieve social goals with legal tools. In this Article, Professors Jones and Goldsmith argue that many long held understandings about where behavior comes from are rapidly obsolescing as a consequence of developments in the various fields constituting behavioral biology. By helping to refine law's understandings of behavior's causes, they argue, behavioral biology can help to improve law's …
Characterizing The Evolutionary Path(S) To Early Homo, Lauren Schroeder, Charles C. Roseman, James M. Cheverud, Rebecca R. Ackermann
Characterizing The Evolutionary Path(S) To Early Homo, Lauren Schroeder, Charles C. Roseman, James M. Cheverud, Rebecca R. Ackermann
James Cheverud
Numerous studies suggest that the transition from Australopithecus to Homo was characterized by evolutionary innovation, resulting in the emergence and coexistence of a diversity of forms. However, the evolutionary processes necessary to drive such a transition have not been examined. Here, we apply statistical tests developed from quantitative evolutionary theory to assess whether morphological differences among late australopith and early Homo species in Africa have been shaped by natural selection. Where selection is demonstrated, we identify aspects of morphology that were most likely under selective pressure, and determine the nature (type, rate) of that selection. Results demonstrate that selection must …
Conservation In The Context Of Climate Change: Practical Guidelines For Land Protection At Local Scales, Kevin Ruddock, Peter August, Christopher Damon, Charles Labash, Pamela Rubinoff, Donald Robadue Jr.
Conservation In The Context Of Climate Change: Practical Guidelines For Land Protection At Local Scales, Kevin Ruddock, Peter August, Christopher Damon, Charles Labash, Pamela Rubinoff, Donald Robadue Jr.
Peter August
Climate change will affect the composition of plant and animal communities in many habitats and geographic settings. This presents a dilemma for conservation programs – will the portfolio of protected lands we now have achieve a goal of conserving biodiversity in the future when the ecological communities occurring within them change? Climate change will significantly alter many plant communities, but the geophysical underpinnings of these landscapes, such as landform, elevation, soil, and geological properties, will largely remain the same. Studies show that extant landscapes with a diversity of geophysical characteristics support diverse plant and animal communities. Therefore, geophysically diverse landscapes …
Individual Cell Growth Rates Of Marine Bacteria, Measured By Bromodeoxyuridine Incorporation, Koji Hamasaki, Richard A. Long, Farooq Azam
Individual Cell Growth Rates Of Marine Bacteria, Measured By Bromodeoxyuridine Incorporation, Koji Hamasaki, Richard A. Long, Farooq Azam
Richard A. Long
We tested the application of 5-bromo-2’-deoxyuridine (BrdU), a thymidine analogue that becomes incorporated into DNA during growth, to measure growth rates of individual marine bacteria cells. Immunocytochemical detection of BrdU incorporation into bacterial DNA has the potential for single-cell-based growth measurement. Optimized procedure for immunocytochemistry was applicable to 14 marine heterotrophic bacterial isolates belonging to g-proteobacteria, α-proteobacteria, Cytophaga-Flavobacterium-Bacteroides (CFB) group and Gram-positive bacteria. The relationship between cell-specific fluorescence intensity and specific growth rate was linearly correlated among CFB group isolates, which indicated a potential of the method for quantitative measurement. Analysis of the detection limit indicated …
Coupling Between Bacterioplankton Species Composition, Population Dynamics, And Organic Matter Degradation, Jarone Pinhassi, Farooq Azam, Johanna Hemphälä, Richard A. Long, Josefina Martinez, Ulla Li Zweifel, Åke Hagström
Coupling Between Bacterioplankton Species Composition, Population Dynamics, And Organic Matter Degradation, Jarone Pinhassi, Farooq Azam, Johanna Hemphälä, Richard A. Long, Josefina Martinez, Ulla Li Zweifel, Åke Hagström
Richard A. Long
To study the effect of substrate addition on short term bacterial population dynamics and species composition in seawater mesocosms were maintained with water collected off Scripps Pier (La Jolla, California USA) Protein enrichment (BSA) triggered a dynamic response from the microbial food web, whereas enrichment with starch had no effect. In the protein enriched mesocosm the number of both nucleoid-containing cells and metabolically active cells increased by 3.0 X 105 cells ml-1 from Day 1 to Day 4 In the same time period the density of a set of 31 phylogenetically different bacteria (α- and g-Proteobactena as well as Flexibacter-Cytophaga-Bacteroides) …
Abundant Protein-Containing Particles In The Sea, Richard A. Long, Farooq Azam
Abundant Protein-Containing Particles In The Sea, Richard A. Long, Farooq Azam
Richard A. Long
The interaction of bacteria with particulate organic matter has implications for organic matter cycling and bacterial ecology in the ocean. Until recently, the focus has been on 'classical' particles visible by unaided eye (marine snow) or light microscopy. Recent discoveries of several new types of abundant particles, from sub-micrometer to sub-marine snow, are changing our ideas of the physical and chemical nature of the particle field with which pelagic bacteria interact. Previous workers have discovered polysaccharide-containing (Alcian Blue stainable) transparent exopolymer particles (TEP) ranging from 3 to 100s of micrometers. Looking for additional components of the sub-marine snow particle field, …
Locomotor Loading Mechanics In The Hindlimbs Of Tegu Lizards (Tupinambis Merianae): Comparative And Evolutionary Implications, K. Megan Sheffield, Michael T. Butcher, S. Katharine Shugart, Jennifer C. Gander, Richard W. Blob
Locomotor Loading Mechanics In The Hindlimbs Of Tegu Lizards (Tupinambis Merianae): Comparative And Evolutionary Implications, K. Megan Sheffield, Michael T. Butcher, S. Katharine Shugart, Jennifer C. Gander, Richard W. Blob
Megan Sheffield
Skeletal elements are usually able to withstand several times their usual load before they yield, and this ratio is known as the bone’s safety factor. Limited studies on amphibians and non-avian reptiles have shown that they have much higher limb bone safety factors than birds and mammals. It has been hypothesized that this difference is related to the difference in posture between upright birds and mammals and sprawling ectotherms; however, limb bone loading data from a wider range of sprawling species are needed in order to determine whether the higher safety factors seen in amphibians and non-avian reptiles are ancestral …
Loading Mechanics Of The Femur In Tiger Salamanders (Ambystoma Tigrinum) During Terrestrial Locomotion, K. Megan Sheffield, Richard W. Blob
Loading Mechanics Of The Femur In Tiger Salamanders (Ambystoma Tigrinum) During Terrestrial Locomotion, K. Megan Sheffield, Richard W. Blob
Megan Sheffield
Salamanders are often used as representatives of the basal tetrapod body plan in functional studies, but little is known about the loads experienced by their limb bones during locomotion. Although salamanders’ slow walking speeds might lead to low locomotor forces and limb bone stresses similar to those of non-avian reptiles, their highly sprawled posture combined with relatively small limb bones could produce elevated limb bone stresses closer to those of avian and mammalian species. This study evaluates the loads on the femur of the tiger salamander (Ambystoma tigrinum) during terrestrial locomotion using three- dimensional measurements of the ground reaction force …
Dna Inside, Lori B. Andrews
Dna Inside, Lori B. Andrews
Lori B. Andrews
Review Of The Nearctic Gallwasp Species Of The Genus Bassettia Ashmead, 1887, With Description Of New Species (Hymenoptera: Cynipidae: Cynipini), Warren G. Abrahamson Ii, G. Melika
Review Of The Nearctic Gallwasp Species Of The Genus Bassettia Ashmead, 1887, With Description Of New Species (Hymenoptera: Cynipidae: Cynipini), Warren G. Abrahamson Ii, G. Melika
Warren G. Abrahamson, II
No abstract provided.
Size And Organic Content Of Eggs Of Marine Annelids, And The Underestimation Of Egg Energy Content By Dichromate Oxidation, William Jaeckle, Bruno Pernet
Size And Organic Content Of Eggs Of Marine Annelids, And The Underestimation Of Egg Energy Content By Dichromate Oxidation, William Jaeckle, Bruno Pernet
William Jaeckle
Dichromate oxidation is a simple technique that is often used to estimate the energy content of eggs in studies of marine invertebrate life histories (1). We used this method to measure the energy contents of the eggs of 12 species of marine annelids. In combination with measures of egg ash-free dry weight (AFDW), these data yielded estimates of AFDW-specific energy density that were mostly lower than the average weight-specific energy density of carbohydrates. This seemed unlikely to be correct, as invertebrate eggs typically contain little carbohydrate and instead are composed primarily of energy-dense protein and lipid (1, 2). After validating …
A Long Way From Home: Transatlantic Sea Star Migration, William Jaeckle, Paul Kehle
A Long Way From Home: Transatlantic Sea Star Migration, William Jaeckle, Paul Kehle
William Jaeckle
For a marine biologist strolling along the eastern coast of South America, finding some sea stars (popularly called starfish, and technically members of the class Asteroidea of the phylum Echinodermata) is not all that unusual. However, when closer inspection reveals the sea stars to be ones that are also found on the shores of the western coast of Africa, the marine biologist now faces an interesting question: How did these sea stars come to be so far from home? Originally published in Consortiumand used with permission.
Taxonomy And Biology Of A New Oecophoridae (Lepidoptera) From Central Chile, T. Heath Ogden
Taxonomy And Biology Of A New Oecophoridae (Lepidoptera) From Central Chile, T. Heath Ogden
T. Heath Ogden
The adult, larva, and pupa of Afdera jimenae Ogden & Parra sp. nov. are described and illustrated. Larvae live in leaf litter throughout all instars and are generalists feeding upon the fallen leaves of a number of different plant species of sclerophyllous forests. Comments on morphological details and bionomics of this species are given. This is the second species of Afdera know for Chile.
The Potential For Ontogenetic Vertical Migration By Larvae Of Bathyal Echinoderms, William Jaeckle, Craig M. Young, Michael G. Devin, Suki U.K. Ekaratne, Sophie B. George
The Potential For Ontogenetic Vertical Migration By Larvae Of Bathyal Echinoderms, William Jaeckle, Craig M. Young, Michael G. Devin, Suki U.K. Ekaratne, Sophie B. George
William Jaeckle
Planktotrophy is a relatively common developmental mode among bathyal and abyssal echinoderms, but the sources of food used by deep-sea planktotrophic larvae remain generally unknown. Very few deep-sea echinoderm larvae have been collected in plankton samples, so we do not know whether larvae migrate to the euphotic zone to feed or if they rely on bacteria or detritus at greater depths. We approached this question indirectly by investigating whether larvae of bathyal echinoids can tolerate the temperatures they would encounter in the euphotic zone and whether they possess sufficient energy stores to migrate to the euphotic zone without feeding. Twenty-four …
Transport And Metabolism Of Alanine And Palmitic Acid By Field-Collected Larvae Of Tedania Ignis (Porifera, Demospongiae): Estimated Consequences Of Limited Label Translocation, William Jaeckle
William Jaeckle
The epidermis of larvae of Tedania ignis(Porifera, Demospongiae) is uniformly ciliated except for the posterior pole. The epidermal cells are long, columnar, and monociliate; each cilium arises from an epidermal crypt; symbiotic bacteria were not observed in larval cells. These lecithotrophic ("nonfeeding") larvae can feed by assimilating dissolved organic materials (DOM) from seawater. Larvae transported both the amino acid alanine (mean = 2.73 pmol larva-1 h-1; [S] = 1 µM) and the fatty acid palmitic acid (mean = 16.27 pmol larva-1 h-1; [S] = 1 µM) from seawater. Following assimilation, the label from alanine was recovered primarily in small molecular …
Multiple Modes Of Asexual Reproduction By Tropical And Subtropical Sea Star Larvae: An Unusual Adaptation For Genet Dispersal And Survival, William Jaeckle
Multiple Modes Of Asexual Reproduction By Tropical And Subtropical Sea Star Larvae: An Unusual Adaptation For Genet Dispersal And Survival, William Jaeckle
William Jaeckle
Sea star larvae (Echinodermata: Asteroidea), collected from the subtropical Northwest Atlantic Ocean, exhibited three distinct modes of asexual reproduction. A number of different bipinnariae and brachiolariae reproduced by paratomous cloning of the posterolateral arms. This morphogenesis was identical to that of larvae assignable to the genus Luidia. A second mode of asexual reproduction involves the autotomization of an anterior portion of the preoral lobe. Primary larvae with preoral lobes of varying sizes and free-swimming preoral lobes of various stages of morphological development were simultaneously collected. The free-swimming preoral lobes developed complete digestive systems and ultimately assumed the form of typical …
Rates Of Energy Consumption And Acquisition By Lecithotrophic Larvae Of Bugula Neritina (Bryozoa: Cheilostomata), William Jaeckle
Rates Of Energy Consumption And Acquisition By Lecithotrophic Larvae Of Bugula Neritina (Bryozoa: Cheilostomata), William Jaeckle
William Jaeckle
Lecithotrophic larvae of the cheilostome bryozoan, Bugula neritina (L.), lose metamorphic competence 12 to 24 h after release from the maternal zooid. The high respiration rate of newly released larvae (mean=306.3 pmol O2 larva-1 h-1, range= 149.3 to 466.6, n=18 trials, 22.5 °C) from adults collected at Link Port, Fort Pierce, Florida during the winter/spring of 1990-1991 reflects their active swimming behavior. The average energy con¬tent per larva was 15.24 mJ (range: 13.35 to 20.17 mJ ind-1, n=5 groups). If all cells have an identical energy content and metabolic rate, then 2 and 20% of the total en¬ergy content would …
Amino Acid Uptake And Metabolism By Larvae Of The Marine Worm Urechis Caupo (Echiura), A New Species In Axenic Culture, William Jaeckle, Donal T. Manahan
Amino Acid Uptake And Metabolism By Larvae Of The Marine Worm Urechis Caupo (Echiura), A New Species In Axenic Culture, William Jaeckle, Donal T. Manahan
William Jaeckle
Axenic (bacteria-free) larval cultures of the marine echiuran worm, Urechis caupo, were reliably obtained by aseptically removing gametes directly from the gamete storage organs. Trochophore larvae only removed neutral amino acids from seawater as measured by high-performance liquid chromatography (HPLC). There was no detectable uptake, as measured by HPLC, of acidic or basic amino acids. Kinetic analysis showed that the transport system for alanine in 4-day-old larvae had a Kt of 4-6 μM and a Jmax of 9-10 pmol larva-1 h-1. Following a 50-min exposure, the majority of the radio-activity (95%) from 14C-alanine was found in the trichlo-roacetic acid-soluble fraction. …