Life Sciences Commons^™

Thrust Production And Chordal Flexion Of The Flukes Of Bottlenose Dolphins Performing Tail Stands At Different Efforts, David Kramer, Maura J. Sheehan, Frank E. Fish

Biology Faculty Publications

Dolphins have become famous for their ability to perform a wide variety of athletic and acrobatic behaviors including high-speed swimming, maneuverability, porpoising and tail stands. Tail stands are a behavior where part of the body is held vertically above the water's surface, achieved through thrust produced by horizontal tail fluke oscillations. Strong, efficient propulsors are needed to generate the force required to support the dolphin's body weight, exhibiting chordwise and spanwise flexibility throughout the stroke cycle. To determine how thrust production, fluke flexibility and tail stroke kinematics vary with effort, six adult bottlenose dolphins (Tursiops truncatus) were tested at three …

The Diversity Of Wolbachia Across The Turtle Ants (Formicidae: Cephalotes Spp.), Corey Reese, Leland C. Graber, Manuela O. Ramalho, Corrie S. Moreau

Biology Faculty Publications

Wolbachia is a widespread and well-known bacterium that can induce a wide range of changes within its host. Ants specifically harbor a great deal of Wolbachia diversity and are useful systems to study endosymbiosis. The turtle ants (Cephalotes) are a widespread group of tropical ants that rely on gut microbes to support their herbivorous diet for their survival, yet little is known of the extent of this diversity. Therefore, studying their endosymbionts and categorizing the diversity of bacteria within Cephalotes hosts could help to delimit species and identify new strains and can help lead to a further understanding of how …

Mitochondrial Gtp Metabolism Controls Reproductive Aging In C. Elegans, Yi-Tang Lee, Marzia Savini, Tao Chen, Yang, Jin, Qian Zhao, Lang Ding, Shihong Max Gao, Jessica N. Sowa, Jue D. Wang, Meng C. Wang

Biology Faculty Publications

Healthy mitochondria are critical for reproduction. During aging, both reproductive fitness and mitochondrial homeostasis decline. Mitochondrial metabolism and dynamics are key factors in supporting mitochondrial homeostasis. However, how they are coupled to control reproductive health remains unclear. We report that mitochondrial GTP (mtGTP) metabolism acts through mitochondrial dynamics factors to regulate reproductive aging. We discovered that germline-only inactivation of GTP-but not ATP-specific succinyl-CoA synthetase (SCS) promotes reproductive longevity in Caenorhabditis elegans. We further identified an age-associated increase in mitochondrial clustering surrounding oocyte nuclei, which is attenuated by GTP-specific SCS inactivation. Germline-only induction of mitochondrial fission factors sufficiently promotes mitochondrial dispersion …

Groundwater-Stream Connections Shape The Spatial Pattern And Rates Of Aquatic Metabolism, Anna Lupon, Lluís Gomez-Gener, Megan Fork, Hjalmar Laudon, Eugènia Martí, William Lidberg, Ryan A. Sponseller

Biology Faculty Publications

A longstanding challenge in stream ecology is to understand how landscape configuration organizes spatial patterns of ecosystem function via lateral groundwater connections. We combined laboratory bioassays and field additions of a metabolic tracer (resazurin) to test how groundwater-stream confluences, or "discrete riparian inflow points " (DRIPs), regulate heterotrophic microbial activity along a boreal stream. We hypothesized that DRIPs shape spatial patterns and rates of aquatic heterotrophic microbial activity by supplying labile dissolved organic matter (DOM) to streams. Laboratory bioassays showed that the potential influence of DRIPs on heterotrophic activity varied spatially and temporally, and was related to their DOM content …

Investigating The Diversity Of Wolbachia Across The Spiny Ants (Polyrhachis), Jenna L. Webb, Leland C. Graber, Manuela O. Ramalho, Corrie S. Moreau

Biology Faculty Publications

Among insects, Wolbachia is an exceedingly common bacterial endosymbiont with a range of consequences of infection. Despite the frequency of Wolbachia infection, very little is known about this bacteria's diversity and role within hosts, especially within ant hosts. In this study, we analyze the occurrence and diversity of Wolbachia across the spiny ants (Polyrhachis), a large and geographically diverse genus. Polyrhachis samples from throughout the host genus' phylogenetic and biogeographical range were first screened for single infections of Wolbachia using the wsp gene and Sanger sequencing. The multilocus sequence typing (MLST) scheme was then used on these singly infected samples …

The Facet Of Human Impact: Solenopsis Invicta Buren, 1972 Spreading Around The Atlantic Forest, Manuela O. Ramalho, Victor H. Nagatani, Juliana M. C. Alves, Otavio G. M. Silva, Eduardo G. P. Fox, Rodrigo F. Souza, Debora Y. Kayano, Ricardo Harakava, Alexandre W. S. Hilsdorf, Maria S. C. Morini

Biology Faculty Publications

The present investigation deals with some aspects of the diversity of fire ants (Hymenoptera: Formicidae) in their native range. The Red Imported Fire Ant Solenopsis invicta is native to the tropical and subtropical inland territories of South America. In Brazil, it mainly occurs around the Pantanal region and across the Paraguay river, a region composed of grasslands which are seasonally flooded. Recent studies have evidenced this fire ant species is gradually spreading to other regions of Brazil. In the present investigation, we surveyed the molecular diversity of S. invicta populations across fragments of Atlantic Forest in Sao Paulo, Brazil, using …

Long‑Term Adaptation To Galactose As A Sole Carbon Source Selects For Mutations Outside The Canonical Gal Pathway, Artemiza A. Martínez, Andrew Conboy, Sean Buskirk, Daniel A. Marad, Gregory I. Lang

Biology Faculty Publications

Galactose is a secondary fermentable sugar that requires specific regulatory and structural genes for its assimilation, which are under catabolite repression by glucose. When glucose is absent, the catabolic repression is attenuated, and the structural GAL genes are fully activated. In Saccharomyces cerevisiae, the GAL pathway is under selection in environments where galactose is present. However, it is unclear the adaptive strategies in response to long-term propagation in galactose as a sole carbon source in laboratory evolution experiments. Here, we performed a 4,000-generation evolution experiment using 48 diploid Saccharomyces cerevisiae populations to study adaptation in galactose. We show that fitness …

Multiple Behaviors For Turning Performance Of Pacific Bluefin Tuna (Thunnus Orientalis), Abigail M. Downs, Allison Kolpas, Barbara A. Block, Frank E. Fish

Biology Faculty Publications

Tuna are known for exceptional swimming speeds, which are possible because of their thunniform lift-based propulsion, large muscle mass and rigid fusiform body. A rigid body should restrict maneuverability with regard to turn radius and turn rate. To test if turning maneuvers by the Pacific bluefin tuna (Thunnus orientalis) are constrained by rigidity, captive animals were videorecorded overhead as the animals routinely swam around a large circular tank or during feeding bouts. Turning performance was classified into three different types: (1) glide turns, where the tuna uses the caudal fin as a rudder; (2) powered turns, where the animal uses …

Untangling The Complex Interactions Between Turtle Ants And Their Microbial Partners, Manuela O. Ramalho, Corrie S. Moreau

Biology Faculty Publications

Background: To understand the patterns of biodiversity it is important to consider symbiotic interactions as they can shape animal evolution. In several ant genera symbiotic interactions with microbial communities have been shown to have profound impacts for the host. For example, we know that for Camponotini the gut community can upgrade the host's diet and is shaped by development and colony interactions. However, what is true for one ant group may not be true for another. For the microbial communities that have been examined across ants we see variation in the diversity, host factors that structure these communities, and the …

Fast And Furious: Energetic Tradeoffs And Scaling Of High-Speed Foraging In Rorqual Whales, William T. Gough, David E. Cade, Max F. Czapanskiy, Jean Potvin, Frank E. Fish, Shirel R. Kahane-Rapport, Matthew S. Savoca, K. C. Bierlich, David W. Johnston, Ari S. Friedlaender, Andy Szabo, Lars Bejder, Jeremy A. Goldbogen

Biology Faculty Publications

Although gigantic body size and obligate filter feeding mechanisms have evolved in multiple vertebrate lineages (mammals and fishes), intermittent ram (lunge) filter feeding is unique to a specific family of baleen whales: rorquals. Lunge feeding is a high cost, high benefit feeding mechanism that requires the integration of unsteady locomotion (i.e., accelerations and maneuvers); the impact of scale on the biomechanics and energetics of this foraging mode continues to be the subject of intense study. The goal of our investigation was to use a combination of multi-sensor tags paired with UAS footage to determine the impact of morphometrics such as …

Community-Powered Urban Stream Restoration: A Vision For Sustainable And Resilient Urban Ecosystems, Mateo Scoggins, Derek B. Booth, Tim Fletcher, Megan Fork, Ana Gonzalez, Rebecca L. Hale, Robert J. Hawley, Allison H. Roy, Erika E. Bilger, Nick Bond, Matthew James Burns, Kristina G. Hopkins, Kate H. Macneale, Eugenia Marti, Kyle S. Mckay, Martin W. Neale, Michael J. Paul, Blanca Rios-Touma, Kathryn L. Russell, Robert F. Smith, Staryn Wagner, Seth Wenger

Biology Faculty Publications

Urban streams can provide amenities to people living in cities, but those benefits are reduced when streams become degraded, potentially even causing harm (disease, toxic compounds, etc.). Governments and institutions invest resources to improve the values and services provided by urban streams; however, the conception, development, and implementation of such projects may not include meaningful involvement of community members and other stakeholders. Consequently, project objectives may be misaligned with community desires and needs, and projects may fail to achieve their goals. In February 2020, the 5(th) Symposium on Urbanization and Stream Ecology, an interdisciplinary meeting held every 3 to 5 …

Slamming Dynamics Of Diving And Its Implications For Diving-Related Injuries, Anupam Pandey, Jisoo Yuk, Brian Chang, Frank E. Fish, Sunghwan Jung

Biology Faculty Publications

In nature, many animals dive into water at high speeds, e.g., humans dive from cliffs, birds plunge, and aquatic animals porpoise and breach. Diving provides opportunities for animals to find prey and escape from predators and is a source of great excitement for humans. However, diving from high platforms can cause severe injuries to a diver. In this study, we demonstrate how similarity in the morphology of diving fronts unifies the slamming force across diving animals and humans. By measuring a time-averaged impulse that increases linearly with the impact height, we are able to estimate the unsteady hydrodynamic forces that …

Bio-Inspired Propulsion: Towards Understanding The Role Of Pectoral Fin Kinematics In Manta-Like Swimming, Alec Menzer, Yuchen Gong, Frank E. Fish, Haibo Dong

Biology Faculty Publications

Through computational fluid dynamics (CFD) simulations of a model manta ray body, the hydrodynamic role of manta-like bioinspired flapping is investigated. The manta ray model motion is reconstructed from synchronized high-resolution videos of manta ray swimming. Rotation angles of the model skeletal joints are altered to scale the pitching and bending, resulting in eight models with different pectoral fin pitching and bending ratios. Simulations are performed using an in-house developed immersed boundary method-based numerical solver. Pectoral fin pitching ratio (PR) is found to have significant implications in the thrust and efficiency of the manta model. This occurs due to more …

G1-Cyclin2 (Cln2) Promotes Chromosome Hypercondensation In Eco1/Ctf7 Rad61 Null Cells During Hyperthermic Stress In Saccharomyces Cerevisiae, Sean Buskirk, Robert V. Skibbens

Biology Faculty Publications

Eco1/Ctf7 is a highly conserved acetyltransferase that activates cohesin complexes and is critical for sister chromatid cohesion, chromosome condensation, DNA damage repair, nucleolar integrity, and gene transcription. Mutations in the human homolog of ECO1 (ESCO2/EFO2), or in genes that encode cohesin subunits, result in severe developmental abnormalities and intellectual disabilities referred to as Roberts syndrome and Cornelia de Lange syndrome, respectively. In yeast, deletion of ECO1 results in cell inviability. Codeletion of RAD61 (WAPL in humans), however, produces viable yeast cells. These eco1 rad61 double mutants, however, exhibit a severe temperature-sensitive growth defect, suggesting that Eco1 or cohesins respond to …

Resolving The Drivers Of Algal Nutrient Limitation From Boreal To Arctic Lakes And Streams, Maria Myrstener, Megan Fork, Ann-Kristin Bergstrom, Isolde Callisto Puts, Demian Hauptmann, Peter D. F. Isles, Ryan M. Burrows, Ryan A. Sponseller

Biology Faculty Publications

Nutrient inputs to northern freshwaters are changing, potentially altering aquatic ecosystem functioning through effects on primary producers. Yet, while primary producer growth is sensitive to nutrient supply, it is also constrained by a suite of other factors, including light and temperature, which may play varying roles across stream and lake habitats. Here, we use bioassay results from 89 lakes and streams spanning northern boreal to Arctic Sweden to test for differences in nutrient limitation status of algal biomass along gradients in colored dissolved organic carbon (DOC), water temperature, and nutrient concentrations, and to ask whether there are distinct patterns and …

Scaling Of Maneuvering Performance In Baleen Whales: Larger Whales Outperform Expectations, Paolo S. Segre, William T. Gough, Edward A. Roualdes, David E. Cade, Max F. Czapanskiy, James Fahlbusch, Shirel R. Kahane-Rapport, William K. Oestreich, Lars Bejder, K. C. Bierlich, Julia A. Burrows, John Calambokidis, Ellen M. Chenoweth, Jacopo Di Clemente, John W. Durban, Holly Fearnbach, Frank E. Fish, Ari S. Friedlaender, Peter Hegelund, David W. Johnston, Douglas P. Nowacek, Machiel G. Oudejans, Gwenith S. Penry, Jean Potvin, Malene Simon, Andrew Stanworth, Janice M. Straley, Andrew Szabo, Simone K. A. Videsen, Fleur Visser, Caroline R. Weir, David N. Wiley, Jeremy A. Goldbogen

Biology Faculty Publications

Despite their enormous size, whales make their living as voracious predators. To catch their much smaller, more maneuverable prey, they have developed several unique locomotor strategies that require high energetic input, high mechanical power output and a surprising degree of agility. To better understand how body size affects maneuverability at the largest scale, we used bio-logging data, aerial photogrammetry and a high-throughput approach to quantify the maneuvering performance of seven species of free-swimming baleen whale. We found that as body size increases, absolute maneuvering performance decreases: larger whales use lower accelerations and perform slower pitch changes, rolls and turns than …

Velocity Field Measurements Of The California Sea Lion Propulsive Stroke Using Bubble Piv, Gino Perrotta, Frank E. Fish, Danielle S. Adams, Ariel M. Leahy, Abigal M. Downs, Megan C. Leftwich

Biology Faculty Publications

California sea lions are among the most agile of swimming mammals. Most marine mammals swim with their hind appendages-flippers or flukes, depending on the species-whereas sea lions use their foreflippers for propulsion and maneuvering. The sea lion's propulsive stroke generates thrust by forming a jet between the flippers and the body and by dragging a starting vortex along the suction side of the flipper. Prior experiments using robotic flippers have shown these mechanisms to be possible, but no flow measurements around live sea lions previously existed with which to compare. In this study, the flow structures around swimming sea lions …

The Role Of California Sea Lion (Zalophus Californianus) Hindflippers As Aquatic Control Surfaces For Maneuverability, Ariel M. Leahy, Frank E. Fish, Sarah J. Kerr, Jenifer A. Zeligs, Stefani Skrovan, Kaitlyn L. Cardenas, Megan C. Leftwich

Biology Faculty Publications

California sea lions (Zalophus californianus) are a highly maneuverable species of marine mammal. During uninterrupted, rectilinear swimming, sea lions oscillate their foreflippers to propel themselves forward without aid from the collapsed hindfiippers, which are passively trailed. During maneuvers such as turning and leaping (porpoising), the hindfiippers are spread into a delta-wing configuration. There is little information defining the role of otarrid hindfiippers as aquatic control surfaces. To examine Z. califomianus hindflippers during maneuvering, trained sea lions were video recorded underwater through viewing windows performing porpoising behaviors and banking turns. Porpoising by a trained sea lion was compared with sea lions …

Scaling Of Oscillatory Kinematics And Froude Efficiency In Baleen Whales, William T. Gough, Hayden J. Smith, Matthew S. Savoca, Max F. Czapanskiy, Frank E. Fish, Jean Potvin, K. C. Bierlich, David E. Cade, Jacopo Di Clemente, John Kennedy, Paolo Segre, Andrew Stanworth, Caroline Weir, Jeremy A. Goldbogen

Biology Faculty Publications

High efficiency lunate-tail swimming with high-aspect-ratio lifting surfaces has evolved in many vertebrate lineages, from fish to cetaceans. Baleen whales (Mysticeti) are the largest swimming animals that exhibit this locomotor strategy, and present an ideal study system to examine how morphology and the kinematics of swimming scale to the largest body sizes. We used data from whale-borne inertial sensors coupled with morphometric measurements from aerial drones to calculate the hydrodynamic performance of oscillatory swimming in six baleen whale species ranging in body length from 5 to 25 m (fin whale, Balaenoptera physalus; Bryde's whale, Balaenoptera edeni; sei whale, Balaenoptera borealis; …

Antibiotic Resistance In Mucosal Bacteria From High Arctic Migratory Salmonids, Kristy Moniz, Virginia K. Walker, Vishal Shah

Biology Faculty Publications

Two related salmonids, Arctic char (Salvelinus alpinus) and lake whitefish (Coregonus clupeaformis) sampled from the high Arctic region of Nunavut, Canada are anadromous fish, migrating annually from the same ice-covered freshwater waterbodies to spend summers in the marine waters of the Arctic Ocean. Microbiota associated with the skin-associated mucus undergo community change coincident with migration, and irrespective of this turnover, antibiotic resistance was detected in mixed bacterial cultures initiated with mucus samples. Although as expected most bacteria were unculturable, however, 5/7 isolates showed susceptibility to a panel of five common antibiotics. The fish were sampled under severe conditions and at …

Diversity Of Navel Microbiome In Young Adults, Shreya Shah, Teresa Donze-Reiner, Vishal Shah

Biology Faculty Publications

Introduction. Human skin microbial communities represent a tremendous source of genetic diversity that evolves as a function of human age. Microbiota differs between regions of oily and moist skin, and appears to stabilize with age.

Aim. We have a minimal understanding of the time frame required for the stabilization of skin microbiota, and the role played by gender. In the current study, we examined the microbiota present in the navel region of college-attending young adults in the age group of 18–25 years and investigated if diversity is associated with gender (male and female).

Method. The study involved 16 female and …

Loading Rate Has Little Influence On Tendon Fascicle Mechanics, Michael V. Rosario, Thomas J. Roberts

Biology Faculty Publications

Mechanically, tendons behave like springs and store energy by stretching in proportion to applied stress. This relationship is potentially modified by the rate at which stress is applied, a phenomenon known as viscosity. Viscoelasticity, the combined effects of elasticity and viscosity, can affect maximum strain, the amount of stored energy, and the proportion of energy recovered (resilience). Previous studies of tendons have investigated the functional effects of viscoelasticity, but not at the intermediate durations of loading that are known to occur in fast locomotor events. In this study, we isolated tendon fascicles from rat tails and performed force-controlled tensile tests …

Energetic And Physical Limitations On The Breaching Performance Of Large Whales, Paolo S. Segre, Jean Potvin, David E. Cade, John Calambokidis, Jacopo Di Clemente, Frank E. Fish, Ari S. Friedlaender, William T. Gough, Shirel R. Kahane-Rapport, Claudia Oliveira, Susan E. Parks, Gwenith S. Penry, Malene Simon, Alison K. Stimpert, David N. Wiley, K. C. Bierlich, Peter T. Madsen, Jeremy A. Goldbogen

Biology Faculty Publications

The considerable power needed for large whales to leap out of the water may represent the single most expensive burst maneuver found in nature. However, the mechanics and energetic costs associated with the breaching behaviors of large whales remain poorly understood. In this study we deployed whale-borne tags to measure the kinematics of breaching to test the hypothesis that these spectacular aerial displays are metabolically expensive. We found that breaching whales use variable underwater trajectories, and that high-emergence breaches are faster and require more energy than predatory lunges. The most expensive breaches approach the upper limits of vertebrate muscle performance, …

Measuring Functional Brain Recovery In Regenerating Planarians By Assessing The Behavioral Response To The Cholinergic Compound Cytisine, Oné R. Pagán, Debra L. Baker, Sean Deats, Mary O'Brien, Rochelle Dymond, Gabriella Demichele

Biology Faculty Publications

Planarians are traditional model invertebrates in regeneration and developmental biology research that also display a variety of quantifiable behaviors useful to screen for pharmacologically active compounds. One such behavior is the expression of seizure-like movements (pSLMs) induced by a variety of substances. Previous work from our laboratory showed that cocaine, but not nicotine, induced pSLMs in intact but not decapitated planarians. Interestingly, as decapitated planarians regenerated their heads, they gradually recovered their sensitivity to cocaine. These results suggested a method to assess planarian brain regeneration and a possible way of identifying compounds that could enhance or hold back brain regeneration. …

Autophagy Protein Nrbf2 Has Reduced Expression In Alzheimer's Brains And Modulates Memory And Amyloid-Beta Homeostasis In Mice, Veronik Lachance, Qian Wang, Eric Sweet, Insup Choi, Cui-Zan Cai, Xu-Xu Zhuang, Jessica Li Jiang, Robert D. Blitzer, Ozlem Bozdagi-Gunal, Bin Zhang, Jia-Hong Lu, Zhenyu Yue

Biology Faculty Publications

Background Dysfunctional autophagy is implicated in Alzheimer's Disease (AD) pathogenesis. The alterations in the expression of many autophagy related genes (ATGs) have been reported in AD brains; however, the disparity of the changes confounds the role of autophagy in AD. Methods To further understand the autophagy alteration in AD brains, we analyzed transcriptomic (RNAseq) datasets of several brain regions (BA10, BA22, BA36 and BA44 in 223 patients compared to 59 healthy controls) and measured the expression of 130 ATGs. We used autophagy-deficient mouse models to assess the impact of the identified ATGs depletion on memory, autophagic activity and amyloid-beta (A …

Scaling Of Swimming Performance In Baleen Whales, William T. Gough, Paolo S. Segre, K. C. Bierlich, David E. Cade, Jean Potvin, Frank E. Fish, Julian Dale, Jacopo Di Clemente, Ari S. Friedlaender, David W. Johnston, Shirel R. Kahane-Rapport, John Kennedy, John H. Long, Machiel Oudejans, Gwenith Penry, Matthew S. Savoca, Malene Simon, Simone K. A. Videsen, Fleur Visser, David N. Wiley, Jeremy O. Goldbogen

Biology Faculty Publications

The scale dependence of locomotor factors has long been studied in comparative biomechanics, but remains poorly understood for animals at the upper extremes of body size. Rorqual baleen whales include the largest animals, but we lack basic kinematic data about their movements and behavior below the ocean surface. Here, we combined morphometrics from aerial drone photogrammetry, whale-borne inertial sensing tag data and hydrodynamic modeling to study the locomotion of five rorqual species. We quantified changes in tail oscillatory frequency and cruising speed for individual whales spanning a threefold variation in body length, corresponding to an order of magnitude variation in …

Water Entry Impact Dynamics Of Diving Birds, Saburel I. Sharker, Sean Holekamp, Mohammad M. Mansoor, Tadd T. Truscott

Biology Faculty Publications

Some seabirds (such as northern gannets and brown boobies) can dive from heights as high as 30 m reaching speeds of up to 24 m s−1 as they impact the water surface. The physical geometry of plunge diving birds, particularly of the beak, allows them to limit high impact forces compared to non-diving birds. Numerically simulated data for one species (northern gannet) provides some insight into the impact forces experienced during diving, however, no reliable experimental data with real bird geometries exist for comparison purposes. This study utilizes eleven 3D printed diving bird models of three types of birds: plunge-diving …

The Effects Of Diet And Mating System On Reproductive (And Post‐Reproductive) Life Span In A Freshwater Snail, Josh R. Auld

Biology Faculty Publications

The length of the reproductive life span, along with the number/frequency/magnitude of reproductive events, quantifies an individual’s potential contribution to the next generation. By examining reproductive life span, and distinguishing it from somatic life span, we gain insight into critical aspects of an individual’s potential fitness as well as reproductive and somatic senescence. Additionally, differentiating somatic and reproductive life spans can provide insight into the existence of a post‐reproductive period and factors that shape its duration. Given the known importance of diet and mating system on resource allocation, I reared individual freshwater snails (Physa acuta) from 22 full‐sib families under …

Demographic Hallmarks Of An Overbrowsed Population State In American Ginseng, James B. Mcgraw, Jennifer L. Chandler

Biology Faculty Publications

Effects of high deer herbivory in North America on populations of favored plant browse species have been well-documented, however since less palatable plants now dominate the understory, we asked whether these species could be vulnerable as well, and if so, what symptoms might signal that this was occurring? Using American ginseng (Panax quinquefoliusL.) as our representative less palatable understory plant, we compared two subpopulations within a single natural population that were differentially exposed to browse; one isolated from deer by growing atop a large, flat-topped boulder, and a browse-exposed subpopulation in the surrounding low-lying area. We tested the hypothesis that …

Experimental Measurement Of Dolphin Thrust Generated During A Tail Stand Using Dpiv, Frank E. Fish, Terrie M. Williams, Erica Sherman, Yae Eun Moon, Vicki Wu, Timothy Wei

Biology Faculty Publications

: Estimation of force generated by dolphins has long been debated. The problem was that indirect estimates of force production for dolphins resulted in low values that could not be validated. Bubble digital particle image velocimetry (DPIV) measured hydrodynamic force production for swimming dolphins and demonstrated high force production. To validate the bubble DPIV and reconcile force production measurements, two bottlenose dolphins (Tursiops truncatus) performing tail stands were measured with bubble DPIV. Microbubbles were generated from a finely porous hose and compressed air source. Displacement of the bubbles by the propulsive motions of the dolphin was tracked with a high-speed …