Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Keyword
-
- Metabolism (3)
- Evolution (2)
- Genetic (2)
- Genetics (2)
- Transcription factor ap-2 (2)
-
- Amphibian (1)
- Amplified fragment length polymorphism (1)
- Anatomy & histology (1)
- Animal active movement (1)
- Animals (1)
- Arabidopsis (1)
- Arabidopsis proteins (1)
- Arrestins (1)
- Arthropoda (1)
- Behavior (1)
- Biological (1)
- Biological evolution (1)
- Carry-over costs (1)
- Cell nucleus (1)
- Cellulose (1)
- Clostridium thermocellum (1)
- Coexistence (1)
- Color morph (1)
- Community (1)
- Complex life cycle (1)
- Costs (1)
- Cotyledon (1)
- Cytokinins (1)
- Damselfly larvae (1)
- Developmental stage (1)
Articles 1 - 14 of 14
Full-Text Articles in Biology
Three Perspectives On Neutrality And Drift In Molecular Evolution, Michael Dietrich
Three Perspectives On Neutrality And Drift In Molecular Evolution, Michael Dietrich
Dartmouth Scholarship
This article offers three contrasting cases of the use of neutrality and drift in molecular evolution. In the first, neutrality is assumed as a simplest case for modeling. In the second and third, concepts of drift and neutrality are developed within the context of population genetics testing and the development and application of the molecular clock.
Outsiders As Innovators In The Life Sciences, Michael Dietrich
Outsiders As Innovators In The Life Sciences, Michael Dietrich
Dartmouth Scholarship
An introduction to the book Outsider Scientists: Routes to Innovation in Biology edited by Oren Harman and Michael Dietrich
Integration Without Unification: An Argument For Pluralism In The Biological Sciences, Sandra D. Mitchell, Michael R. Dietrich
Integration Without Unification: An Argument For Pluralism In The Biological Sciences, Sandra D. Mitchell, Michael R. Dietrich
Dartmouth Scholarship
In this article, we consider the tension between unification and pluralism in biological theory. We begin with a consideration of historical efforts to establish a unified understanding of evolution in the neo‐Darwinian synthesis. The fragmentation of the evolutionary synthesis by molecular evolution suggests the limitations of the general unificationist ideal for biology but not necessarily for integrating explanations. In the second half of this article, we defend a specific variety of pluralism that allows for the integration required for explanations of complex phenomena without unification on a large scale.
Enzyme–Microbe Synergy During Cellulose Hydrolysis By Clostridium Thermocellum, Yanpin Lu, Yi-Heng P. Zhang, Lee R. Lynd
Enzyme–Microbe Synergy During Cellulose Hydrolysis By Clostridium Thermocellum, Yanpin Lu, Yi-Heng P. Zhang, Lee R. Lynd
Dartmouth Scholarship
Specific cellulose hydrolysis rates (g of cellulose/g of cellulase per h) were shown to be substantially higher (2.7- to 4.7-fold) for growing cultures of Clostridium thermocellum as compared with purified cellulase preparations from this organism in controlled experiments involving both batch and continuous cultures. This “enzyme–microbe synergy” requires the presence of metabolically active cellulolytic microbes, is not explained by removal of hydrolysis products from the bulk fermentation broth, and appears due to surface phenomena involving adherent cellulolytic microorganisms. Results support the desirability of biotechnological processes featuring microbial conversion of cellulosic biomass to ethanol (or other products) in the absence of …
A Subset Of Arabidopsis Ap2 Transcription Factors Mediates Cytokinin Responses In Concert With A Two-Component Pathway, Aaron M. Rashotte, Michael G. Mason, Claire E. Hutchison, Fernando J. Ferreira, G. Eric Schaller, Joseph J. Kieber
A Subset Of Arabidopsis Ap2 Transcription Factors Mediates Cytokinin Responses In Concert With A Two-Component Pathway, Aaron M. Rashotte, Michael G. Mason, Claire E. Hutchison, Fernando J. Ferreira, G. Eric Schaller, Joseph J. Kieber
Dartmouth Scholarship
The plant hormone cytokinin regulates numerous growth and developmental processes. A signal transduction pathway for cytokinin has been elucidated that is similar to bacterial two-component phosphorelays. In Arabidopsis, this pathway is comprised of receptors that are similar to sensor histidine kinases, histidine-containing phosphotransfer proteins, and response regulators (ARRs). There are two classes of response regulators, the type-A ARRs, which act as negative regulators of cytokinin responses, and the type-B ARRs, which are transcription factors that play a positive role in mediating cytokinin-regulated gene expression. Here we show that several closely related members of the Arabidopsis AP2 gene family of …
Genetic And Maternal Determinants Of Effective Dispersal: The Effect Of Sire Genotype And Size At Birth In Side-Blotched Lizards, Barry Sinervo, Ryan Calsbeek, Tosha Comendant, Christiaan Both
Genetic And Maternal Determinants Of Effective Dispersal: The Effect Of Sire Genotype And Size At Birth In Side-Blotched Lizards, Barry Sinervo, Ryan Calsbeek, Tosha Comendant, Christiaan Both
Dartmouth Scholarship
We assessed genetic factors on progeny dispersal due to sire color morph genotypes in a field pedigree and lab crosses, and we measured maternal effects by studying both natural and experimentally induced egg size variation. Progeny were released into nature upon hatching, but we recorded dispersal distance at maturity, which reflects effective dispersal after viability selection has run its course. Progeny dispersal was significantly affected by sire genotype. Progeny from orange sires dispersed the farthest. Progeny from blue sires dispersed intermediate distances. Progeny from yellow sires were the most philopatric. Sire genotype effects interacted with egg size. In particular, enlarged …
Coexistence Of The Niche And Neutral Perspectives In Community Ecology, Mathew A. Leibold, Mark A. Mcpeek
Coexistence Of The Niche And Neutral Perspectives In Community Ecology, Mathew A. Leibold, Mark A. Mcpeek
Dartmouth Scholarship
The neutral theory for community structure and biodiversity is dependent on the assumption that species are equivalent to each other in all important ecological respects. We explore what this concept of equivalence means in ecological communities, how such species may arise evolutionarily, and how the possibility of ecological equivalents relates to previous ideas about niche differentiation. We also show that the co-occurrence of ecologically similar or equivalent species is not incompatible with niche theory as has been supposed, because niche relations can sometimes favor coexistence of similar species. We argue that both evolutionary and ecological processes operate to promote the …
An Essential Role For Endocytosis Of Rhodopsin Through Interaction Of Visual Arrestin With The Ap-2 Adaptor, Nicholas R. Orem, Luxi Xia, Patrick J. Dolph
An Essential Role For Endocytosis Of Rhodopsin Through Interaction Of Visual Arrestin With The Ap-2 Adaptor, Nicholas R. Orem, Luxi Xia, Patrick J. Dolph
Dartmouth Scholarship
Previously, we have identified a class of retinal degeneration mutants in Drosophila in which the normally transient interaction between arrestin2 (Arr2) and rhodopsin is stabilized and the complexes are rapidly internalized into the cell body by receptor-mediated endocytosis. The accumulation of protein complexes in the cytoplasm eventually results in photoreceptor cell death. We now show that the endocytic adapter protein AP-2 is essential for rhodopsin endocytosis through an Arr2-AP-2beta interaction, and mutations in Arr2 that disrupt its interaction with the beta subunit of AP-2 prevent endocytosis-induced retinal degeneration. We further demonstrate that if the interaction between Arr2 and AP-2 is …
A Kinesin-Like Calmodulin-Binding Protein In Chlamydomonas: Evidence For A Role In Cell Division And Flagellar Functions, Erin E. Dymek, Daniel Goduti, Tal Kramer, Elizabeth F. Smith
A Kinesin-Like Calmodulin-Binding Protein In Chlamydomonas: Evidence For A Role In Cell Division And Flagellar Functions, Erin E. Dymek, Daniel Goduti, Tal Kramer, Elizabeth F. Smith
Dartmouth Scholarship
Kinesin-like calmodulin-binding protein, KCBP, is a novel member of the C-kinesin superfamily first discovered in flowering plants. This minus-end-directed kinesin exhibits Ca(2+)-calmodulin-sensitive motor activity in vitro and has been implicated in trichome morphogenesis and cell division. A homologue of KCBP is also found in the unicellular, biflagellate green alga Chlamydomonas reinhardtii (CrKCBP). Unlike plant cells, Chlamydomonas cells do not form trichomes and do not assemble a phragmoplast before cell division. To test whether CrKCBP is involved in additional microtubule-based processes not observed in plants, we generated antibodies against the putative calmodulin-binding domain and used these antibodies in biochemical and localization …
Moments Of Truth In Genetic Medicine, Michael Dietrich
Moments Of Truth In Genetic Medicine, Michael Dietrich
Dartmouth Scholarship
Review of Moments of Truth in Genetic Medicine by Susan Lindee, 2005.
Time Constraints Mediate Predator-Induced Plasticity In Immune Function, Condition, And Life History, Robby Stoks, Marjan De Block, Stefanie Slos, Wendy Van Doorslaer, Jens Rolff
Time Constraints Mediate Predator-Induced Plasticity In Immune Function, Condition, And Life History, Robby Stoks, Marjan De Block, Stefanie Slos, Wendy Van Doorslaer, Jens Rolff
Dartmouth Scholarship
The simultaneous presence of predators and a limited time for development imposes a conflict: accelerating growth under time constraints comes at the cost of higher predation risk mediated by increased foraging. The few studies that have addressed this trade-off have dealt only with life history traits such as age and size at maturity. Physiological traits have largely been ignored in studies assessing the impact of environmental stressors, and it is largely unknown whether they respond independently of life history traits. Here, we studied the simultaneous effects of time constraints, i.e., as imposed by seasonality, and predation risk on immune defense, …
Linking Direct And Indirect Data On Dispersal: Isolation By Slope In A Headwater Stream Salamander, Winsor H. Lowe, Gene E. Likens, Mark A. Mcpeek, Don C. Buso
Linking Direct And Indirect Data On Dispersal: Isolation By Slope In A Headwater Stream Salamander, Winsor H. Lowe, Gene E. Likens, Mark A. Mcpeek, Don C. Buso
Dartmouth Scholarship
There is growing recognition of the need to incorporate information on movement behavior in landscape-scale studies of dispersal. One way to do this is by using indirect indices of dispersal (e.g., genetic differentiation) to test predictions derived from direct data on movement behavior. Mark–recapture studies documented upstream-biased movement in the salamander Gyrinophilus porphyriticus (Plethodontidae). Based on this information, we hypothesized that gene flow in G. porphyriticus is affected by the slope of the stream. Specifically, because the energy required for upstream dispersal is positively related to slope, we predicted gene flow to be negatively related to change in elevation between …
Integration Without Unification: An Argument For Pluralism In The Biological Sciences, Michael Dietrich, Sandra D. Mitchell
Integration Without Unification: An Argument For Pluralism In The Biological Sciences, Michael Dietrich, Sandra D. Mitchell
Dartmouth Scholarship
In this article, we consider the tension between unification and pluralism in biological theory. We begin with a consideration of historical efforts to establish a unified understanding of evolution in the neo-Darwinian synthesis. The fragmentation of the evolutionary synthesis by molecular evolution suggests the limitations of the general unificationist ideal for biology but not necessarily for integrating explanations. In the second half of this article, we defend a specific variety of pluralism that allows for the integration required for explanations of complex phenomena without unification on a large scale.
From Mendel To Molecules: A Brief History Of Evolutionary Genetics, Michael Dietrich
From Mendel To Molecules: A Brief History Of Evolutionary Genetics, Michael Dietrich
Dartmouth Scholarship
No abstract provided.