Biology Commons^™

Census And Mapping Of Chorro Creek Bog Thistle In Reservoir Canyon, San Luis Obispo, Ca, Tyler Michael Lutz

Biological Sciences

Chorro Creek bog thistle (Cirsium fontinale var. obispoense) is a federally endangered variety of Fountain thistle endemic to western San Luis Obispo County. The U.S. Fish and Wildlife Service knows of nineteen populations, many with multiple colonies. A population was discovered in the Reservoir Canyon Natural Reserve in 2001, but has not been monitored or described since the time of its discovery. In fall of 2013, a census of the population was performed, the four colonies were mapped, and a floristic survey was conducted. A field experiment was initiated to determine if reducing the riparian canopy coverage can …

Phylogeography Of The California Sheephead, Semicossyphus Pulcher: The Role Of Deep Reefs As Stepping Stones And Pathways To Antitropicality, Marloes Poortvliet, Gary C. Longo, Kimberly Selkoe, Paul H. Berber, Crow White, Jennifer E. Caselle, Alejandro Perez-Matus, Steven D. Gaines, Giacomo Bernardi

Biological Sciences

In the past decade, the study of dispersal of marine organisms has shifted from focusing predominantly on the larval stage to a recent interest in adult movement. Antitropical distributions provide a unique system to assess vagility and dispersal. In this study, we have focused on an antitropical wrasse genus, Semicossyphus, which includes the California sheephead, S. pulcher, and Darwin's sheephead, S. darwini. Using a phylogenetic approach based on mitochondrial and nuclear markers, and a population genetic approach based on mitochondrial control region sequences and 10 microsatellite loci, we compared the phylogenetic relationships of these two species, as well …

Luxs In Bacteria Isolated From 25- To 40-Million-Year-Old Amber, Tasha M. Santiago-Rodriguez, Ana R. Patrício, Jessica I. Rivera, Mariel Coradin, Alfredo Gonzalez, Gabriela Tirado, Raúl J. Cano, Gary A. Toranzos

Biological Sciences

Interspecies bacterial communication is mediated by autoinducer-2, whose synthesis depends on luxS. Due to the apparent universality of luxS (present in more than 40 bacterial species), it may have an ancient origin; however, no direct evidence is currently available. We amplified luxS in bacteria isolated from 25- to 40-million-year-old amber. The phylogenies and molecular clocks of luxS and the 16S rRNA gene from ancient and extant bacteria were determined as well. Luminescence assays using Vibrio harveyi BB170 aimed to determine the activity of luxS. While the phylogeny of luxS was very similar to that of extant Bacillus spp., …

Rov-Based Tracking Of A Shallow Water Nocturnal Squid, Samuel Yim, Christopher M. Clark, Timothy Peters, Vladimir Prodanov, Pat Fidopiastis

Biological Sciences

This paper describes the use of a Remotely Operated Vehicle (ROV) equipped with a monocular vision system to find and track the squid Euprymna scolopes, so that motion behaviors of the squid could be characterized through the use of off-line image processing and state estimation. The ROV was deployed for several nights at several nearshore locations off Oahu, resulting in 10 hours of squid footage. Using blob-tracking image processing techniques and a Particle Filter state estimator, the squid can be detected and tracked. The position, velocity, and acceleration of the squid relative to the stationary ROV can be determined. Experiment …

Evaluation Of Species Distribution Models By Resampling Of Sites Surveyed A Century Ago By Joseph Grinnell, Adam B. Smith, Maria J. Santos, Michelle S. Koo, Karen M.C. Rowe, Kevin C. Rowe, James L. Patton, John D. Perrine, Steven R. Beissinger, Craig Moritz

Biological Sciences

Species distribution models (SDMs) are commonly applied to predict species’ responses to anticipated global change, but lack of data from future time periods precludes assessment of their reliability. Instead, performance against test data in the same era is assumed to correlate with accuracy in the future. Moreover, high-confidence absence data is required for testing model accuracy but is often unavailable since a species may be present when undetected. Here we evaluate the performance of eight SDMs trained with historic (1900–1939) or modern (1970–2009) climate data and occurrence records for 18 mammalian species. Models were projected to the same or the …

Assessing Coral Reef Fish Population And Community Changes In Response To Marine Reserves In The Dry Tortugas, Florida, Usa, Jerald S. Ault, Steven G. Smith, James A. Bohnsack, Jiangang Luo, Natalia Zurcher, David B. Mcclellan, Tracy A. Ziegler, David E. Hallac, Matt Patterson, Michael W. Feeley, Benjamin I. Ruttenberg, John Hunt, Dan Kimball, Billy Causey

Biological Sciences

The efficacy of no-take marine reserves (NTMRs) to enhance and sustain regional coral reef fisheries was assessed in Dry Tortugas, Florida, through 9 annual fishery-independent research surveys spanning 2 years before and 10 years after NTMR implementation. A probabilistic sampling design produced precise estimates of population metrics of more than 250 exploited and non-target reef fishes. During the survey period more than 8100 research dives utilizing SCUBA Nitrox were optimally allocated using stratified random sampling. The survey domain covered 326 km², comprised of eight reef habitats in four management areas that offered different levels of resource protection: the …

Microbial Communities In Pre-Columbian Coprolites, Tasha M. Santiago-Rodriguez, Yvonne M. Narganes-Storde, Luis Chanlatte, Edwin Crespo-Torres, Gary A. Toranzos, Rafael Jiménez-Flores, Alice Hamrick, Raul J. Cano

Biological Sciences

The study of coprolites from earlier cultures represents a great opportunity to study an “unaltered” composition of the intestinal microbiota. To test this, pre-Columbian coprolites from two cultures, the Huecoid and Saladoid, were evaluated for the presence of DNA, proteins and lipids by cytochemical staining, human and/or dog-specific Bacteroides spp. by PCR, as well as bacteria, fungi and archaea using Terminal Restriction Fragment analyses. DNA, proteins and lipids, and human-specific Bacteroides DNA were detected in all coprolites. Multidimensional scaling analyses resulted in spatial arrangements of microbial profiles by culture, further supported by cluster analysis and ANOSIM. Differences between the microbial …

The Correlation Between Veldt Grass (Ehrharta Calycina) And Reproductive Condition Of The Lompoc Kangaroo Rat (Dipodomys Heermanni Arenae), Jacqueline Mae Bates

Biological Sciences

The invasive species, Veldt grass (Ehrharta calycina), has come to dominate coastal dune shrub vegetation along the Central Coast of California. Along with creating many land management obstacles, this grass has become dominant in the open habitat of Lompoc Kangaroo Rats (Dipodomys heermanni arenae). It is hypothesized that, due to a lack of suitable kangaroo rat habitat, during the breeding season months of March and April, there will be significantly fewer reproductively active females in areas of relatively high Veldt grass cover as opposed to relatively low Veldt grass cover. This study used data from a …

Differences In The Health Of Domesticated Sheep (Ovis Aries) Pastured In Wild And Agricultural Landscapes, Corine Giroux

Biological Sciences

The purpose of this study was to compare the health of sheep grazed in a quasi-wild landscape (Norman’s Kill Farm, an abandoned dairy) as part of a targeted grazing research project, to that of sheep in a conventional agricultural pasture setting (Longfield Farm). This study tested the null hypothesis that there is no difference between the health and nutrition of sheep in a domestic setting and those in a wild setting. Sheep on the quasi-wild landscape were healthier than those on the agricultural setting, having healthier body condition scores. The mean body condition scores of the sheep at Longfield was …

Molecular Modulation Of Single And Multi-Species Biofilm Formation By Orally-Associated Bacteria, Daniel Sellers

Biological Sciences

Biofilms are aggregates of bacterial cells attached to a surface. Oral biofilms (“plague”) are major contributors to tooth decay (dental caries) and are a potential conduit for infection and disease. These biofilms have been shown to be resistant to removal by traditional oral hygiene practices. Novel prophylactic and in situ treatment methods are therefore needed to address this problem. While Oral biofilms have been shown to contain hundreds of species of bacteria we focus on three relevant organisms: Streptococcus mutans, Streptococcus sanguinis, and Actinomyces naeslundii (A. oris). Of the many bacteria involved in cavity formation and tooth decay, S. mutans …

Achieving The Triple Bottom Line In The Face Of Inherent Trade-Offs Among Social Equity, Economic Return, And Conservation, Benjamin S. Halpern, Carissa J. Klein, Christopher J. Brown, Maria Beger, Hedley S. Grantham, Sangeeta Mangubhai, Mary Ruckelshaus, Vivitskaia J. Tulloch, Matt Watts, Crow White, Hough P. Possingham

Biological Sciences

Triple–bottom-line outcomes from resource management and conservation, where conservation goals and equity in social outcomes are maximized while overall costs are minimized, remain a highly sought-after ideal. However, despite widespread recognition of the importance that equitable distribution of benefits or costs across society can play in conservation success, little formal theory exists for how to explicitly incorporate equity into conservation planning and prioritization. Here, we develop that theory and implement it for three very different case studies in California (United States), Raja Ampat (Indonesia), and the wider Coral Triangle region (Southeast Asia). We show that equity tends to trade off …

Evaluating Tradeoffs Among Ecosystem Services To Inform Marine Spatial Planning, Sarah E. Lester, Christopher Costello, Benjamin S. Halpern, Steven D. Gaines, Crow White, John A. Barth

Biological Sciences

A central challenge for natural resource management is developing rigorous yet practical approaches for balancing the costs and benefits of diverse human uses of ecosystems. Economic theory has a long history of evaluating tradeoffs in returns from different assets to identify optimal investment strategies. There has been recent progress applying this framework to the delivery of ecosystem services in land use planning. However, despite growing national and international interest in marine spatial planning, there is a lack of parallel frameworks in the marine realm. This paper reviews an ecosystem service tradeoff analysis framework and provides a more comprehensive synthesis for …

Marine Protected Areas And Resilience To Sedimentation In The Solomon Islands, B. S. Halpern, K. A. Selkoe, Crow White, S. Albert, S. Aswani, M. Lauer

Biological Sciences

The ability of marine protected areas (MPAs) to provide protection from indirect stressors, via increased resilience afforded by decreased impact from direct stressors, remains an important and unresolved question about the role MPAs can play in broader conservation and resource management goals. Over a five-year period, we evaluated coral and fish community responses inside and outside three MPAs within the Roviana Lagoon system in Solomon Islands, where sedimentation pressure from upland logging is substantial. We found little evidence that MPAs decrease impact or improve conditions and instead found some potential declines in fish abundance. We also documented modest to high …

A Socratic Method For Surveying Students’ Readiness To Study Evolution, William D. Stansfield

Biological Sciences

Before beginning a series of presentations on evolution, it would be prudent to survey the general level of students’ understanding of prerequisite basic concepts of reproduction, heredity, ontology, and phenotypic diversity so that teachers can avoid devoting time to well-known subjects of general knowledge and can spend more time on subjects that are unknown, forgotten, or misunderstood by most students. This article outlines a Socratic method for surveying and teaching to address these concerns.

Teaching Evolution & The Nature Of Science Via The History Of Debates About The Levels At Which Natural Selection Operates, William D. Stansfield

Biological Sciences

Students should not graduate from high school without understanding that scientific debates are essential components of scientific methodology. This article presents a brief history of ongoing debates regarding the hypothesis that group selection is an evolutionary mechanism, and it serves as an example of the role that debates play in correcting faulty ideas and stimulating new research in the pursuit of extending scientific knowledge.

Beneath The Surface Overview, Elizabeth Sikkema

Biological Sciences

As a Wildlife Biology major at Cal Poly, I was able to express my passion for the ocean and beaches in planning and co-designing a beach and dive clean up Earth Day celebration as my senior project. This event took place at Avila Beach on April 21st and was hosted by the Central Coast Aquarium. It was open to the public in attempts to promote outreach and awareness of coastal conservation, allowing volunteers to participate in the clean-ups and visit the Aquarium. The event was a success, involving over 100 volunteers, collecting and recycling 150 pounds of trash and also …

Rapid Invasion Of Indo-Pacific Lionfishes (Pterois Volitans And Pterois Miles) In The Florida Keys, Usa: Evidence From Multiple Pre- And Post-Invasion Data Sets, Benjamin I. Ruttenberg, Pamela J. Schofield, J. Lad Akins, Alejandro Acosta, Michael W. Feeley, Jeremiah Blondeau, Steven G. Smith, Jerald S. Ault

Biological Sciences

Over the past decade, Indo-Pacific lionfishes, Pterois volitans (Linnaeus, 1758) and Pterois miles (Bennett, 1828), venomous members of the scorpionfish family (Scorpaenidae), have invaded and spread throughout much of the tropical and subtropical northwestern Atlantic Ocean and Caribbean Sea. These species are generalist predators of fishes and invertebrates with the potential to disrupt the ecology of the invaded range. Lionfishes have been present in low numbers along the east coast of Florida since the 1980s, but were not reported in the Florida Keys until 2009. We document the appearance and rapid spread of lionfishes in the Florida Keys using multiple …

Dynamics Of An Acute Coral Disease Outbreak Associated With The Macroalgae Dictyota Spp. In Dry Tortugas National Park, Florida, Usa, Marilyn E. Brandt, Benjamin I. Ruttenberg, Rob Waara, Jeff Miller, Brian Witcher, Andrew J. Estep, Matt Patterson

Biological Sciences

Reports of coral disease outbreaks have increased in recent decades, but often few details are known about these outbreaks, such as environmental triggers, associated biological variables, or even the precise temporal span of the outbreak. Here we document an acute outbreak of a rapid tissue loss disease on the highest live coral cover (15%–30%) reefs within Dry Tortugas National Park, Florida, USA. This disease exhibited similar signs to white plague disease with the notable exception that a white film often was observed on the recently denuded skeleton. The temporal span of the disease was short (<2 mo). Partial mortality was recorded but there was no detectable impact to overall coral cover. A significant increase and then decrease in the cover of macroalgae, primarily of the genus Dictyota, occurred simultaneously …

An Experimental Evaluation Of The Use Of C3 Δ13C Plant Tissue As A Proxy For The Paleoatmospheric Δ13Co2 Signature Of Air, B. H. Lomax, C. A. Knight, J. A. Lake

Biological Sciences

Previous work suggests that the relationship between the carbon isotope composition of air (d13Ca) and plant leaf tissue (d13Cp) can be used to track changes in the carbon isotope composition of paleo-atmospheric CO2. Here we test this assertion in a series of experiments using the model plant Arabidopsis thaliana grown under a range of atmospheric CO2 concentrations relevant to geologic time (380, 760, 1000, 1500, 2000 and 3000 ppm). Nested within these CO2 experiments water availability was controlled (giving two sets of experimental plants; low and high water treatment at each CO2 concentration) to manipulate stomatal opening, a key process …

Environmental Stress Proteomics Of Two Blue Mussel (Genus Mytilus) Congeners, Lars Tomanek

Biological Sciences

Abstract of paper presented at the 28th Congress of the New European Society of Comparative Physiology and Biochemistry Proceedings: Bilbao, Spain.

Gene Transcripts Encoding Hypoxia-Inducible Factor (Hif) Exhibit Tissue- And Muscle Fiber Type-Dependent Responses To Hypoxia And Hypercapnic Hypoxia In The Atlantic Blue Crab, Callinectes Sapidus, Kristin M. Hardy, Chandler R. Follett, Louis E. Burnett, Sean Lema

Biological Sciences

Hypoxia inducible factor (HIF) is a transcription factor that under low environmental oxygen regulates the expression of suites of genes involved in metabolism, angiogenesis, erythropoiesis, immune function, and growth. Here, we isolated and sequenced partial cDNAs encoding hif-α and arnt/hif-β from the Atlantic blue crab, Callinectes sapidus, an estuarine species that frequently encounters concurrent hypoxia (low O₂) and hypercapnia (elevated CO₂). We then examined the effects of acute exposure (1 h) to hypoxia (H) and hypercapnic hypoxia (HH) on relative transcript abundance for hif-α and arnt/hif-β in …

Investigation Of The Importance Of Rock Chemistry For Saxicolous Lichen Communities Of The New Idria Serpentinite Mass, San Benito County, California, Usa, Nishanta Rajakaruna, Kerry Knudsen, Alan M. Fryday, Ryan E. O'Dell, Nathaniel S. Pope, Fred C. Olday, Suzie Woolhouse

Biological Sciences

Although several lichen inventories exist for European ultramafic sites, only four surveys of serpentine lichens for North America have been published to date. Of those, only one has been conducted in California. We conducted a survey of saxicolous lichens from ultramafic rocks (including nephrite, partially serpentinized peridotite, and serpentinite) and non-ultramafic rocks (including silica-carbonate, shale, and sandstone) at the New Idria serpentinite mass, San Benito County, California. X-ray Fluorescence Analysis of the rocks from which the lichens were collected revealed significant elemental differences between the ultramafic and non-ultramafic rocks for 26 of the 32 major and trace elements analyzed. We …

Characterization Of A Vibrio Fischeri Aminopeptidase And Evidence For Its Influence On An Early Stage Of Squid Colonization, Pat M. Fidopiastis, Bethany A. Rader, David G. Gerling, Nestor A. Gutierrez, Katherine H. Watkins, Michelle West Frey, Spencer V. Nyholm, Cheryl A. Whistler

Biological Sciences

Vibrio fischeri cells are the sole colonists of a specialized light organ in the mantle cavity of the sepiolid squid Euprymna scolopes. The process begins when the bacteria aggregate in mucus secretions outside the light organ. The cells eventually leave the aggregate, enter the light organ, and encounter a rich supply of peptides. The need to dissociate from mucus and presumably utilize peptides led us to hypothesize that protease activity is integral to the colonization process. Protease activity associated with whole cells of Vibrio fischeri strain ES114 was identified as the product of a putative cell membrane-associated aminopeptidase (PepN). To …

How Do Host Sex And Reproductive State Affect Host Preference And Feeding Duration Of Ticks?, Nicholas B. Pollock, Larisa K. Vredevoe, Emily N. Taylor

Biological Sciences

Parasitism is one of the most notable forms of symbiosis in the biological world, with nearly all organisms hosting parasites. In many vertebrates, males have higher ectoparasite burdens than females, especially when testosterone concentrations are elevated. Furthermore, reproductive females may have higher ectoparasite burdens than non-reproductive females. It is possible that testosterone-stimulated behaviors in males and offspring investment by females incur energetic costs that inhibit immune function. If questing ticks can sense host sex or reproductive condition prior to attachment, they could potentially choose hosts with the poorest immune function, thereby leading to improved feeding success and decreased feeding duration. …

Stressors And Threats To The Flora Of Acadia National Park, Maine: Current Knowledge, Information Gaps, And Future Directions, Tanner B. Harris, Nishanta Rajakaruna, Sarah J. Nelson, Peter D. Vaux

Biological Sciences

Acadia National Park is a center of plant diversity in northeastern North America. The Park's varied habitats and flora are sensitive to a number of natural and anthropogenic perturbations. Stressors such as invasive plants, pest and pathogens, ozone, acidic fog and sulfur deposition, nitrogen deposition, heavy metals, fire and fire suppression, over-browsing, visitor use, hurricanes, and climate change have all had effects on the Park's habitats and plant species at some point and it is unclear how many of these stressors are currently affecting the flora of Acadia National Park. We discuss the botanical diversity of Acadia, assess the natural …

Hypoxia-Sensitive Gene Expression In The Gastrocnemius Muscle Following Chronic Hind Limb Ischemia, Andrew Tilton

Biological Sciences

Chronic ischemia, caused by the formation atherosclerotic plaque occlusions in major conduit arteries, is the leading cause of morbidity and mortality in western societies. Vascular remodeling can help compensate for the adverse effects of atherosclerotic plaque formation. Vascular remodeling relies heavily on vascular endothelial growth factor (VEGF), a critical protein that contributes to all forms of vascular formation and remodeling including angiogenesis, arteriogenesisand vasculogenesis. VEGF itself is up-regulated by the transcription factor, hypoxia inducible factor 1 alpha (HIF-1α), which becomes activated in low oxygen environments.

Through the use of animal chronic hindlimb ischemia models, these genes can be evaluated as …

The Spatial Games: Investigating The Spatial Distribution Of Anax And Select Prey As A Function Of Predator-Prey Interactions, Shane Elizabeth Johnson, Nene Kumashe Ugbah

Biological Sciences

Our study investigated the spatial distribution and movement behavior of predatory dragonfly larvae (Anax) and of two prey types: mosquito larvae and amphipods. Predator-prey interactions have important consequences for the population dynamics of both predator and prey groups and these interactions can shape community structure. We measured behavior of each prey type in the presence of the Anax predator and the behavior of the predator in the presence of these alternative prey types. Observations were made in five-gallon aquaria where a grid pattern allowed us to track the number of moves made by individuals. We compiled data from …

Probing The T-Box Riboswitch: A Novel, High-Throughput Transcription Reporter Assay Using A Fluorophore-Binding Aptamer, Nishtha Modi

Biological Sciences

In most Gram-positive bacteria, including important pathogens, expression of many aminoacyl tRNA synthetase (aaRS) genes is controlled by the tRNA substrate specific to each of these enzymes. This riboswitch regulatory mechanism is unique to Gram-positive bacteria and because correct and efficient aminoacylation of tRNAs is essential to an organism’s viability, it is an ideal target for the development of new antibiotics. The 5’-untranslated region (5’UTR) of the aaRS mRNA adopts a conformation that determines whether readthrough or termination of transcription occurs by interacting with unacylated or acylated tRNA, respectively. Our goal is to uncover a new class of small molecules …

The Senescence-Associated Secretory Phenotype (Sasp) And Redox-Dependent Invasion Of Metastatic Cancer Cells, Brooke A. Pati

Biological Sciences

Throughout your lifetime renewable tissues and those which are exposed to prolonged inflammation experience an accumulation of senescent cells. These cells have previously been shown to acquire the senescence-associated secretory phenotype (SASP) that promotes proliferation and tumorigenesis of epithelial cells, thus increasing the invasive ability of tumor cells (1). SASP is characterized by an upregulation in mRNA levels of a number of secretory factors, such as growth factors, cytokines, and chemokines. It has been shown that lifetime exposure to oxidative stress can influence cell cytoskeleton reorganization and influence aging processes (2). In addition matrix metalloproteinases are key SASP factors that …

The Distribution Of 4-Nonylphenol In Marine Organisms Of North American Pacific Coast Estuaries, Jennifer Diehl, Sarah E. Johnson, Kang Xia, Amy West, Lars Tomanek

Biological Sciences

One of the chemical breakdown products of nonylphenol ethoxylates, 4-nonylphenol (4-NP), accumulates in organisms and is of concern as an environmental pollutant due to its endocrine disrupting effects. We measured 4-NP levels in the seawater, sediment, and twelve organisms within the California estuary, Morro Bay, and examined biomagnification of 4-NP using stable isotope abundances (δ¹⁵N and δ¹³C) to quantify trophic position. 4-NP concentrations in organisms from Morro Bay included 25000 ± 8600 ng g⁻¹ lw in liver of California sea lion, 14000 ± 5600 ng g⁻¹ lw in liver of harbor porpoise, 138000 …