Biology Commons^™

Do Thick Leaves Avoid Thermal Damage In Critically Low Wind Speeds?, A. Leigh, S. Sevanto, M. C. Ball, J. D. Close, D. S. Ellsworth, Charles A. Knight, A. B. Nicotra, S. Vogel

Biological Sciences

• Transient lulls in air movement are rarely measured, but can cause leaf temperature to rise rapidly to critical levels. The high heat capacity of thick leaves can damp this rapid change in temperature. However, little is known about the extent to which increased leaf thickness can reduce thermal damage, or how thick leaves would need to be to have biological significance. We evaluated quantitatively the contribution of small increases in leaf thickness to the reduction in thermal damage during critically low wind speeds under desert conditions.

• We employed a numerical model to investigate the effect of thickness relative …

Ecosystem Service Tradeoff Analysis Reveals The Value Of Marine Spatial Planning For Multiple Ocean Uses, Crow White, Benjamin S. Halpern, Carrie V. Kappel

Biological Sciences

Marine spatial planning (MSP) is an emerging responsibility of resource managers around the United States and elsewhere. A key proposed advantage of MSP is that it makes tradeoffs in resource use and sector (stakeholder group) values explicit, but doing so requires tools to assess tradeoffs. We extended tradeoff analyses from economics to simultaneously assess multiple ecosystem services and the values they provide to sectors using a robust, quantitative, and transparent framework. We used the framework to assess potential conflicts among offshore wind energy, commercial fishing, and whale-watching sectors in Massachusetts and identify and quantify the value from choosing optimal wind …

Ear Length As A Diagnostic Character For Identifying Species Of Kangaroo Rats, Daniel W. Ziebron

Biological Sciences

The following study examines the use of ear length as a diagnostic field character for differentiating between species of Kangaroo rats in San Luis Obispo County. Data was taken from a study of Kangaroo rats in the Guadalupe-Nipomo Dunes National Wildlife Refuge, as well as various collections under the supervision of Francis X. Villablanca, Ph. D. and California Polytechnic State University, San Luis Obispo. An ANOVA was used to compare subspecies within Dipodomys heermanni and t-tests were used to compare ear lengths between Dipodomys heermanni and Dipodomys venustus. The analysis shows a statistically significant difference and supports the hypothesis …

Science & The Senses: Perceptions & Deceptions, William D. Stansfield

Biological Sciences

Science requires the acquisition and analysis of empirical (sense-derived) data. Given the same physical objects or phenomena, the sense organs of all people do not respond equally to these stimuli, nor do their minds interpret sensory signals identically. Therefore, teachers should develop lectures on human sensory systems that include some common examples of sensory limitations, variations, deficiencies, malfunctions, and diseases (as discussed herein) because they have important implications for conducting scientific investigations, science education, and introspection that are seldom included in biology textbooks. Students need to be made aware of the human tendency to self deception in order to avoid …

Potential For Barn Owl As Rodent Biological Control In Central California Vineyards, Hannah Tillmann

Biological Sciences

The pocket gopher (Thomomys bottae) and voles (Microtus spp.) cause significant economic damage to vineyards. In response, many growers have taken steps to attract Barn Owls (Tyto alba) to their properties to help keep these rodent populations in check. This research project investigated Barn Owl consumption of pocket gophers and voles in Central California vineyards in order to assess the efficiency of this integrated pest management strategy. I collected a total of 715 owl pellets from five vineyard locations in Templeton and Paso Robles, California over an eight-month period during nesting and post-fledging seasons. I …

Fishing Top Predators Indirectly Affects Condition And Reproduction In A Reef-Fish Community, S.M. Walsh, S.L. Hamilton, Bi. Ruttenberg, M.K. Donovan, S.A. Sandin

Biological Sciences

To examine the indirect effects of fishing on energy allocation in non-target prey species, condition and reproductive potential were measured for five representative species (two-spot red snapper Lutjanus bohar, arc-eye hawkfish Paracirrhites arcatus, blackbar devil Plectroglyphidodon dickii, bicolour chromis Chromis margaritifer and whitecheek surgeonfish Acanthurus nigricans) from three reef-fish communities with different levels of fishing and predator abundance in the northern Line Islands, central Pacific Ocean. Predator abundance differed by five to seven-fold among islands, and despite no clear differences in prey abundance, differences in prey condition and reproductive potential among islands were found. Body condition …

Dobzhansky's Dictum: An Object Lesson For Critical Thinking, William D. Stansfield

Biological Sciences

A creationist has called Dobzhansky's dictum a myth. Discussion of this debate could be used as an object lesson for critical thinking.

Spontaneous Multiscale Phase Separation Within Fluorinated Xerogel Coatings For Fouling-Release Surfaces, Anastasiya Sokolova, Joseph J. Bailey, Grant T. Waltz, Lenora H. Brewer, John A. Finlay, Jill Fornalik, Dean Wendt, Maureen E. Callow, James A. Callow, Frank V. Bright, Michael R. Detty

Biological Sciences

Four-component xerogel films consisting of 1 mole-% n-octadecyltrimethoxysilane (C18) and 50 mole-% tetraethoxysilane (TEOS) in combination with 1–24 mole-% tridecafluoro-1,1,2,2-tetrahydrooctyltriethoxysilane (TDF) and 25–48 mole-% n-octyltriethoxysilane (C8) and a 1:49:50 mole-% C18/TDF/TEOS were prepared. Settlement of barnacle cyprids and removal of juvenile barnacles, settlement of zoospores of the alga Ulva linza, and strength of attachment of 7-day sporelings (young plants) of Ulva were compared amongst the xerogel formulations. Several of the xerogel formulations were comparable to poly(dimethylsiloxane) elastomer with respect to removal of juvenile barnacles and removal of sporeling biomass. The 1:4:45:50 and 1:14:35:50 C18/TDF/C8/TEOS xerogels displayed some phase …

Evaluation Of Bio-Optical Inversion Of Spectral Irradiance Measured From An Autonomous Underwater Vehicle, Mark A. Moline, Ian Robbins, Brian Zelenke, W. Scott Pegau, Hemantha Wijesekera

Biological Sciences

Autonomous underwater vehicles (AUVs) can map water conditions at high spatial (horizontal and vertical) and temporal resolution, including under cloudy conditions when satellite and airborne remote sensing are not feasible. As part of the RADYO program, we deployed a passive radiometer on an AUV in the Santa Barbara Channel and off the coast of Hawaii to apply existing bio-optical algorithms for characterizing the optical constituents of coastal seawater (i.e., dissolved organic material, algal biomass, and other particles). The spectral differences between attenuation coefficients were computed from ratios of downwelling irradiance measured at depth and used to provide estimates of the …

Can Vertical Migrations Of Dinoflagellates Explain Observed Bioluminescence Patterns During An Upwelling Event In Monterey Bay, California?, Igor Shulman, Bradley Penta, Mark A. Moline, Steven H.D. Haddock, Stephanie Anderson, Matthew J. Oliver, Peter Sakalaukus

Biological Sciences

Extensive AUVs surveys showed that during the development of upwelling, bioluminescent dinoflagellates from the northern part of the Monterey Bay, California (called the upwelling shadow area), were able to avoid advection by southward flowing currents along the entrance to the Bay, while non-bioluminescent phytoplankton were advected by currents. It is known that vertical swimming of dinoflagellates to deeper layers helps them avoid losses due to advection. In the present paper, we investigate if modeling dinoflagellates’ vertical swimming can explain the observed dinoflagellates’ ability to avoid advection during the upwelling development. The dynamics of a dinoflagellate population is modeled with the …

Sirtuin-Induced Protein Deacetylation Affects The Heat Shock Response In Blue Mussel Congeners (Mytilus), M. Beam, M. Zuzow, L. Tomanek

Biological Sciences

The warm-adapted Mediterranean blue mussel species Mytilus galloprovincialis invaded southern California during the last century and has since replaced the cold-adapted native M. trossulus from its southern range, possibly due to climate change. Based on previous proteomic analyses, we hypothesized that the more heat-sensitive M. trossulus switches from NADH-producing metabolic pathways that may generate reactive oxygen species (ROS) to NADPH-producing pathways that are able to scavenge ROS during severe heat stress (32°C). We further linked these changes to the activity of the mitochondrial NAD-dependent deacetylase, sirtuin-5, which has been shown to regulate many metabolic pathways. To test the latter hypothesis, …

The Proteomic Response To Acute Heat Stress After Acclimation To Fluctuating Temperatures In The Eurythermal Porcelain Crab, Petrolisthes Cinctipes, Michael A. Garland, Holland Elder, David A. Hurt, Jonathon H. Stillman, Lars Tomanek

Biological Sciences

The porcelain crab Petrolisthes cinctipes inhabits the high intertidal along the Pacific coast between British Columbia and central California and is an emerging model organism to study the effects of environmental stress. In its habitat it experiences not only variability in average temperature but also variability in temperature fluctuations. To investigate the effect of temperature fluctuations, we characterized the heat shock response at 30°C for 6 h by acclimating individuals to three different acclimation treatments: 10°C, 10-20°C (4 h), and 10-30°C (4 h) on a daily basis for one month. We dissected claw muscle and separated proteins by 2D gel …

Experimentally Altered Navigational Demands Induce Changes In The Cortical Forebrain Of Free-Ranging Northern Pacific Rattlesnakes (Crotalus O. Oreganus), Matthew L. Holding, Julius A. Frazier, Emily N. Taylor, Christine R. Strand

Biological Sciences

The hippocampus of birds and mammals plays a crucial role in spatial memory and navigation. The hippocampus exhibits plasticity in adulthood in response to diverse environmental factors associated with spatial demands placed on an animal. The medial and dorsal cortices of the telencephalon of squamate reptiles have been implicated as functional homologues to the hippocampus. This study sought to experimentally manipulate the navigational demands placed on free-ranging northern Pacific rattlesnakes (Crotalus o. oreganus) to provide direct evidence of the relationship between spatial demands and neuroplasticity in the cortical telencephalon of the squamate brain. Adult male rattlesnakes were radio-tracked for 2 …

The Proteomic Response Of Mytilus Californianus To Acute Oxidative Stress In The Presence Of A Sirtuin Inhibitor, H. Chilton, J. Mier, M. Zuzow, L. Tomanek

Biological Sciences

The ribbed mussel (Mytilus californianus) occurs in the in the rocky intertidal zone along the Pacific coast of North America where it experiences greatly varying environmental conditions in terms of temperature and hypoxia, stressors that are known to induce oxidative stress. It has been hypothesized that while under acute heat stress, related Mytilus congeners undergo a shift in redox potential through the reduction of NADH fueled respiration pathways to the production of the reducing agent NADPH as a potential defensive mechanism against the production of reactive oxygen species. In addition, it has been hypothesized that sirtuins (a family …

Proteomic Responses Of Mytilus Congeners To Hypo-Saline Stress, M. Z. Zuzow, L. Serafini, L. Hitt, J. Valenzuela, L. Tomanek

Biological Sciences

The invading Mediterranean blue mussel species Mytilus galloprovincialis requires higher salinity levels than the more hypo-saline tolerant and native M.trossulus,which it replaced from its southern range in California, possibly due to climate change.It is also the warm-adapted congener.Hypo-salinity,due to an increase in extreme precipitation events,has been hypothesized to limit the expansion of the invader.By comparing the proteomic responses of the congeners to acute hypo-saline stress we were trying to identify the interspecific differences that set limits to hypo-saline stress and assess their contribution to the range shifts.We exposed mussels to acute hypo-saline(100%, 85% and 70% salinity)stress for 4h followed …

Proteomic Analysis Of Hyposalinity Stress In The Ascidian Species Ciona Savignyi And C. Intestinalis, James S. Koman, Lars Tomanek

Biological Sciences

The ascidian species Ciona savignyi and C. intestinalis are invasive species but show interspecific differences in their population response to hypo-saline stress associated with heavy winter-run off events that are predicted to become more frequent due to climate change. Despite an almost world-wide distribution, C. intestinalis seems to be more susceptible to hypo-saline stress than the geographically more limited C. savignyi. Given that the genomes of both species are fully sequenced, we were able to compare their proteomic response to both acute and chronic salinity to characterize the mechanisms that are responsible for setting tolerance limits to hyposaline conditions …

Proteomic Response Of Tidal-Rhythm Entrained Mytilus Californianus To Acute Aerial Heat Stress, D. Hernandez, M. Schuman, L. Tomanek

Biological Sciences

The rocky intertidal mussel species Mytilus californianus is native to the Pacific coast of North America. It is frequently exposed to temperatures that can induce the cellular stress response due to the tidal rhythm. Instead of acclimating mussels to common conditions in the laboratory for several weeks, we collected mussels from a site with mussel body temperature recordings (specimens’ thermal history) and immediately started experimentation by mimicking the tidal rhythm with different levels of heat stress over multiple low tides and with different recovery periods. By using individuals that were entrained to the tidal rhythm and by maintaining it, we …

The Discovery Of Insulin: A Case Study Of Scientific Methodology, William D. Stansfield

Biological Sciences

The nature of scientific research sometimes involves a trial-and-error procedure. Popular reviews of successful results from this approach often sanitize the story by omitting unsuccessful trials, thus painting the rosy impression that research simply follows a direct route from hypothesis to experiment to scientific discovery. The discovery of insulin is a classical case study in this genre that begs for an explanation to our students because it is so often ignored or misrepresented even in biology and physiology textbooks.

Bioluminescence In The High Arctic During The Polar Night, J. Berge, A.S. Båtnes, G. Johnsen, S.M. Blackwell, Mark A. Moline

Biological Sciences

This study examines the composition and activity of the planktonic community during the polar night in the high Arctic Kongsfjord, Svalbard. Our results are the first published evidence of bioluminescence among zooplankton during the Arctic polar night. The observations were collected by a bathyphotometer detecting bioluminescence, integrated into an autonomous underwater vehicle, to determine the concentration and intensity of bioluminescent flashes as a function of time of day and depth. To further understand community dynamics and composition, plankton nets were used to collect organisms passing through the bathyphotometer along with traditional vertical net tows. Additionally, using a moored bathyphotometer closed …

New Metrics For Managing And Sustaining The Ocean’S Bounty, Heather Tallis, Sarah E. Lester, Mary Ruckelshaus, Mark Plummer, Karen Mcleod, Anne Guerry, Sandy Andelman, Margaret R. Caldwell, Marc Conte, Stephen Copps, David Fox, Rod Fujita, Steven D. Gaines, Guy Gelfenbaum, Barry Gold, Peter Kareiva, Choong-Ki Kim, Kai Lee, Michael Papenfus, Scott Redman, Brian Silliman, Lisa Wainger, Crow White

Biological Sciences

Policies are arising around the world, most recently in the United States, that mandate the implementation of marine spatial planning as a practical pathway towards ecosystem-based management. In the new United States ocean policy, and several other cases around the globe, ecosystem services are at the core of marine spatial planning, but there is little guidance on how ecosystem services should be measured, making it hard to implement this new approach. A new framework is shown here for practical, rigorous ecosystem service measurement that highlights contributions from both natural and social systems. The novel three-step framework addresses traditional shortcomings of …

Mycorrhizal Colonization Of Hypericum Perforatum L. (Hypericaceae) From Serpentine And Granite Outcrops On The Deer Isles, Maine, Naveed Davoodian, Jason Bosworth, Nishanta Rajakaruna

Biological Sciences

Given the paucity of literature on plant-fungal interactions on serpentine soils and limited investigation of serpentine geoecology in eastern North America, we examined mycorrhizal colonization of Hypericum perforatum from adjacent serpentine and granite outcrops on the Deer Isles, ME to determine whether plants were differentially colonized based on substrate. We coincided our sampling with three phenologic stages of H. perforatum (preflowering, flowering, postflowering) to determine possible differences in colonization based on plant phenology. The levels of mycorrhizal colonization in H. perforatum were not significantly different between serpentine and granite sites, while levels of colonization in postflowering plants were significantly higher …

A Collaborative Approach To Investigate Site Fidelity, Home Range, And Homing Behavior Of Cabezon (Scorpaenichthys Marmoratus), Carlos Mireles, Royden Nakamura, Dean Wendt

Biological Sciences

Understanding the area use requirements of species targeted for protection by marine protected areas (MPAs) is critical to the future conservation efforts of economically important fish species. Knowledge of home range size and site fidelity is essential in determining whether species will benefit from the protection offered by a MPA, the size of the area needed to protect individuals, and the extent to which surrounding unprotected areas may be supplemented through post-recruitment movement or “spillover”. We utilized a traditional mark and recapture approach, along with GIS spatial analysis to investigate the site fidelity, home range, and homing behavior of the …

Utilizing Fishermen Knowledge And Expertise: Keys To Success For Collaborative Fisheries Research, Noëlle Yochum, Richard M. Starr, Dean Wendt

Biological Sciences

Collaborative fisheries research provides a mechanism for integrating the unique knowledge, experience, and skills of fishermen and scientists. It is a joint intellectual endeavor that begins with the inception of a project and continues until its final stages, with each group having mutual investment in—and ownership of— the project. Collaborative fisheries research promotes communication and trust among fishermen, scientists, and managers and can provide much-needed scientifically valid data for fisheries management. It can enhance federal and state management data collection programs, which span broad sections of coastline, by increasing the ability to detect changes in local metapopulations that may be …

Parasite Infection And Sand Coarseness Increase Sand Crab (Emerita Analoga) Burrowing Time, Gita R. Kolluru, Zachary S. Green, Larisa K. Vredevoe, Matthew R. Kuzma, Sera N. Ramadan, Marc R. Zosky

Biological Sciences

Parasites with indirect life cycles require trophic transmission from intermediate hosts to definitive (vertebrate) hosts. Transmission may be facilitated if parasite infection alters the behavior of intermediate hosts such that they are more vulnerable to predation. Vulnerability to predation may also be influenced by abiotic factors; however, rarely are the effects of parasites and abiotic factors examined simultaneously. The swash zone of sandy beaches is a particularly harsh environment. Sand crabs (Emerita analoga) burrow rapidly in the swash zone to avoid predators and dislodgment. We examined prevalence and abundance of the acanthocephalan parasite Profilicollis altmani in sand crabs, …

Climate Change, Body Size, And Phenotype Dependent Dispersal, Shannon J. Mccauley, Karen E. Mabry

Biological Sciences

No abstract provided.

Educational Curriculum Standards & Standardized Educational Tests: Comparing Apples & Oranges?, William D. Stansfield

Biological Sciences

Mandated biology curriculum standards and standardized tests may vary widely from one state to another, making academic-performance comparisons among the states problematic. This report outlines the effects of the “No Child Left Behind” law and uses California as a test case against which teachers in other states may make comparisons of their own biology curriculum standards and tests. Several sources are cited that offer sample multiple-choice questions that have appeared on previous California standardized tests for sciences/life sciences/biology. These examples, and critique thereof, may help teachers better prepare their own tests to improve student performance in meeting the state's curriculum …

Season And Sex Of Host Affect Intensities Of Ectoparasites In Western Fence Lizards (Sceloporus Occidentalis) On The Central Coast Of California, Anthony S. Lumbad, Larisa K. Vredevoe, Emily N. Taylor

Biological Sciences

Seasonal variability in intensities of ectoparasites of western fence lizards (Sceloporus occidentalis) was quantified in spring, summer, and autumn 2008. Lizards were suspended over pans of water in the laboratory to enumerate replete western black-legged ticks (Ixodes pacificus) and mites. Intensity of ectoparasites was greatest in spring. On average, mites comprised the greatest proportion of ectoparasites, followed by larval and nymphal ticks, respectively. Mites were on lizards year-round. Overall intensity of ticks was greatest in spring, but low during summer and autumn. Males were more heavily parasitized by ticks than females in spring, whereas females had …

The Proteomic Response Of Sea Squirts (Genus Ciona) To Acute Heat Stress: A Global Perspective On The Thermal Stability Of Proteins, Loredana Serafini, Jay B. Hann, Dietmar Kültz, Lars Tomanek

Biological Sciences

Congeners belonging to the genus Ciona have disparate distributions limited by temperature. Ciona intestinalis is more widespread with a cosmopolitan distribution ranging from tropical to sub-arctic zones, while Ciona savignyi is limited to temperate-latitudes of the northern Pacific Ocean. To compare the heat stress response between congeners, we quantified changes in protein expression using proteomics. Animals were exposed to 22 °C, 25 °C, and 28 °C for 6 h, then recovered at a control temperature (13 °C) for 16 h (high heat stress experiment). In a second experiment we exposed animals to lower levels of heat stress at 18 °C, …

Addressing Biased Occurrence Data In Predicting Potential Sierra Nevada Red Fox Habitat For Survey Prioritization, Casey Cleve, John D. Perrine, Barbara Holzman, Ellen Hines

Biological Sciences

The Sierra Nevada red fox Vulpes vulpes necator is listed as a threatened species under the California Endangered Species Act. It originally occurred throughout California’s Cascade and Sierra Nevada mountain regions. Its current distribution is unknown but should be determined in order to guide management actions. We used occurrence data from the only known population, in the Lassen Peak region of northern California, combined with climatic and remotely sensed variables, to predict the species’ potential distribution throughout its historic range. These model predictions can guide future surveys to locate additional fox populations. Moreover, they allow us to compare the relative …

Bridging The Marine-Terrestrial Disconnect To Improve Marine Coastal Zone Science And Management, Benjamin I. Ruttenberg, Elise F. Granek

Biological Sciences

Coastal zone ecosystems sit between larger terrestrial and marine environments and, therefore, are strongly affected by processes occurring in both systems. Marine coastal zone systems provide a range of benefits to humans, and yet many have been significantly degraded as a result of direct and indirect human impacts. Management efforts have been hampered by disconnects both between management and scientific research and across linked marine–terrestrial systems. Management jurisdictions often start or end at the shoreline, and multiple agencies at different levels of government often have overlapping or conflicting management goals or priorities, or suffer from a lack of knowledge or …