Life Sciences Commons^™

Eugenics And Modern Biology: Critiques Of Eugenics, 1910-1945, Garland E. Allen

Biology Faculty Publications & Presentations

Eugenics in most western countries in the first four decades of the twentieth century was based on the idea that genes control most human phenotypic traits, everything from physical features such as polydactyly and eye color to physiological conditions such as the A-B-O blood groups to mental and personality traits such as “feeblemindedness”, alcoholism and pauperism. It assessing the development of the eugenics movement – its rise and decline between 1900 and 1950 – it is important to recognize that its naïve assumptions and often flawed methodologies were openly criticized at the time by scientists and non-scientists alike. This paper …

A Synthesis Of Plant Invasion Effects On Biodiversity Across Spatial Scales, Kristin I. Powell, Jonathan M. Chase, Tiffany M. Knight

Biology Faculty Publications & Presentations

PREMISE OF THE STUDY:

Invasive plant species are typically thought to pose a large threat to native biodiversity, and local-scale studies typically confirm this view. However, plant invaders rarely cause regional extirpations or global extinctions, causing some to suggest that invasive species' influence on native biodiversity may not be so dire. We aim to synthesize the seemingly conflicting literature in plant invasion biology by evaluating the effects of invasive plant species across spatial scales.

METHODS:

We first conducted a meta-analysis on the effects of invasive plants on the species richness of invaded communities across a range of spatial extents. We …

On The Utility Of Population Models For Invasive Plant Management: Response To Evans And Davis, Eleanor A. Pardini, John M. Drake, Tiffany M. Knight

Biology Faculty Publications & Presentations

No abstract provided.

Will The Use Of Less Fecund Cultivars Reduce The Invasiveness Of Perennial Plants?, Tiffany M. Knight, Kayri Havens, Pati Vitt

Biology Faculty Publications & Presentations

Many invasive species were originally introduced for horticultural purposes, and several continue to be profitable for the green (nursery, horticulture, and landscape) industry. Recently, some plant suppliers have marketed less fecund cultivars of several invasive species, including glossy buckthorn (Frangula alnus), burning bush (Euonymus alatus), and Japanese barberry (Berberis thunbergii), as “safe” alternatives to invasive relatives. We use published matrix population models to simulate the effect of reducing fecundity on the population growth rates of invasive species. We show that large changes in fecundity result in relatively small changes to the population growth rates of long-lived species, which suggests that …

Society For The Advancement Of Biology Education Research (Saber), Erika G. Offerdahl, Teri Balser, Clarissa Dirks, Kathryn Miller, Jennifer L. Momsen, Lisa Montplaisir, Marcy Osgood, Karen Sirum, Mary Pat Wenderoth, Brian White, William B. Wood, Michelle Withers, Robin Wright

Biology Faculty Publications & Presentations

No abstract provided.

Myosin Vi Regulates Actin Structure Specialization Through Conserved Cargo-Binding Domain Sites, Mamiko Isaji, Marta Lenartowska, Tatsuhiko Noguchi, Deborah J. Frank, Kathryn G. Miller

Biology Faculty Publications & Presentations

Actin structures are often stable, remaining unchanged in organization for the lifetime of a differentiated cell. Little is known about stable actin structure formation, organization, or maintenance. During Drosophila spermatid individualization, long-lived actin cones mediate cellular remodeling. Myosin VI is necessary for building the dense meshwork at the cones' fronts. We test several ideas for myosin VI's mechanism of action using domain deletions or site-specific mutations of myosin VI. The head (motor) and globular tail (cargo-binding) domains were both needed for localization at the cone front and dense meshwork formation. Several conserved partner-binding sites in the globular tail previously identified …

Mechanosensitive Channels: What Can They Do And How Do They Do It?, Elizabeth S. Haswell, Rob Phillips, Douglas C. Rees

Biology Faculty Publications & Presentations

While mechanobiological processes employ diverse mechanisms, at their heart are force-induced perturbations in the structure and dynamics of molecules capable of triggering subsequent events. Among the best characterized force-sensing systems are bacterial mechanosensitive channels. These channels reflect an intimate coupling of protein conformation with the mechanics of the surrounding membrane; the membrane serves as an adaptable sensor that responds to an input of applied force and converts it into an output signal, interpreted for the cell by mechanosensitive channels. The cell can exploit this information in a number of ways: ensuring cellular viability in the presence of osmotic stress and …

Two Mechanosensitive Channel Homologs Influence Division Ring Placement In Arabidopsis Chloroplasts, Margaret E. Wilson, Gregory S. Jensen, Elizabeth S. Haswell

Biology Faculty Publications & Presentations

Chloroplasts must divide repeatedly to maintain their population during plant growth and development. A number of proteins required for chloroplast division have been identified, and the functional relationships between them are beginning to be elucidated. In both chloroplasts and bacteria, the future site of division is specified by placement of the Filamentous temperature sensitive Z (FtsZ) ring, and the Min system serves to restrict FtsZ ring formation to mid-chloroplast or mid-cell. How the Min system is regulated in response to environmental and developmental factors is largely unstudied. Here, we investigated the role in chloroplast division played by two Arabidopsis thaliana …

Expression And Characterization Of The Bacterial Mechanosensitive Channel Mscs In Xenopus Laevis Oocytes., Elizabeth S. Haswell, Grigory Maksaev

Biology Faculty Publications & Presentations

We have successfully expressed and characterized mechanosensitive channel of small conductance (MscS) from Escherichia coli in oocytes of the African clawed frog, Xenopus laevis. MscS expressed in oocytes has the same single-channel conductance and voltage dependence as the channel in its native environment. Two hallmarks of MscS activity, the presence of conducting substates at high potentials and reversible adaptation to a sustained stimulus, are also exhibited by oocyte-expressed MscS. In addition to its ease of use, the oocyte system allows the user to work with relatively large patches, which could be an advantage for the visualization of membrane deformation. …