Life Sciences Commons^™

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

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

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

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

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 …

The Influence Of Topographic And Dynamic Cyclic Variables On The Distribution Of Small Cetaceans In A Shallow Coastal System, Marijke N. De Boer, Mark P. Simmonds, Peter J.H. Reijnders, Geert Aarts

Mark P. Simmonds, OBE

The influence of topographic and temporal variables on cetacean distribution at a fine-scale is still poorly understood. To study the spatial and temporal distribution of harbour porpoise Phocoena phocoena and the poorly known Risso’s dolphin Grampus griseus we carried out land-based observations from Bardsey Island (Wales, UK) in summer (2001–2007). Using Kernel analysis and Generalized Additive Models it was shown that porpoises and Risso’s appeared to be linked to topographic and dynamic cyclic variables with both species using different core areas (dolphins to the West and porpoises to the East off Bardsey). Depth, slope and aspect and a low variation …

The Effects Of Temperature And Daylength On The Rosa Polyphenism In The Buckeye Butterfly, Precis Coenia (Lepidoptera: Nymphalidae), Kelly C. Smith

Kelly C Smith

In North Carolina, Precis coenia that emerge during the Summer months exhibit a ventral hindwing (VHW) with well-defined reddish-brown and brown pattern elements on a light tan background. During late Summer and early Fall, however, individuals begin to appear with poorly defined or obscured pattern elements on a dark reddish-brown background. The present study shows that the Fall (rosa) color morph can be induced by either low rearing temperatures or short daylengths. The effect of such conditions seems to be cumulative throughout the larval life, although animals are much more sensitive during the last 24 hours of larval life and …

The Ups And Downs Of Knowledge Infrastructures In Science: Implications For Data Management, Christine L. Borgman, Peter T. Darch, Ashley E. Sands, Jillian C. Wallis, Sharon Traweek

Christine L. Borgman

The promise of technology-enabled, data-intensive scholarship is predicated upon access to knowledge infrastructures that are not yet in place. Scientific data management requires expertise in the scientific domain and in organizing and retrieving complex research objects. The Knowledge Infrastructures project compares data management activities of four large, distributed, multidisciplinary scientific endeavors as they ramp their activities up or down; two are big science and two are small science. Research questions address digital library solutions, knowledge infrastructure concerns, issues specific to individual domains, and common problems across domains. Findings are based on interviews (n=113 to date), ethnography, and other analyses of …

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

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

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

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

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

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 …

Reflections From The Garden: Developing A Critical Literacy Of Food Practices, Deborah Adelman, Shamili Sandiford

Deborah Adelman

No abstract provided.

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

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

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

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

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

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 …

Charles Birch: Synthesis And Hope, Rowan Cahill

Rowan Cahill

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. …