Diatom Flora In Subterranean Ecosystems: A Review, 2014 University of South Florida
Diatom Flora In Subterranean Ecosystems: A Review, Elisa Falasco, Luc Ector, Marco Isaia, Carlos E. Wetzel, Lucien Hoffmann, Francesca Bona
International Journal of Speleology
In scarcity of light and primary producers, subterranean ecosystems are generally extremely oligotrophic habitats, receiving poor supplies of degradable organic matter from the surface. Human direct impacts on cave ecosystems mainly derive from intensive tourism and recreational caving, causing important alterations to the whole subterranean environment. In particular, artificial lighting systems in show caves support the growth of autotrophic organisms (the so-called lampenflora), mainly composed of cyanobacteria, diatoms, chlorophytes, mosses and ferns producing exocellular polymeric substances (EPSs) made of polysaccharides, proteins, lipids and nucleic acids. This anionic EPSs matrix mediates to the intercellular communications and participates to the chemical exchanges ...
Internesting Diving Behavior And Population Structure Of Hawksbill Sea Turtles (Eretmochelys Imbricata) On St. Croix, Usvi, 2014 Indiana University – Purdue University Fort Wayne
Internesting Diving Behavior And Population Structure Of Hawksbill Sea Turtles (Eretmochelys Imbricata) On St. Croix, Usvi, Jacob E. Hill
Hawksbill sea turtles (Eretmochelys imbricata) are distributed circumtropically and populations in many locations have been severely depleted. Developing management plans for this species is hindered by major gaps in knowledge concerning habitat use, behavior, and population structure. This study addresses these knowledge gaps for hawksbill sea turtles nesting at Sandy Point National Wildlife Refuge, St. Croix, US Virgin Islands. Specifically, I will focus on research priorities identified by the US Fish and Wildlife Service in the Recovery Plan for Hawksbill Sea Turtles in the US Caribbean Sea.
The first chapter addresses Recovery Plan Objective 111: Identify Important Nesting Beaches. Three ...
A Tragedy Exposed? Clear Growth Medium Reveals Competing Roots, 2014 University of Kentucky
A Tragedy Exposed? Clear Growth Medium Reveals Competing Roots, Christopher H. Karounos, Deric Miller, Philip Crowley, Nicholas Mcletchie
Tragedy of the Commons (ToC) is the exploitation of an open-access resource that is exploited by selfish individuals to the detriment of all. Examples include open sea fisheries, cattle grazing, pollution, deforestation and plants competing over shared soil nutrients and space. Tragically, these resources become depleted and plants become severely resource limited. Our study seeks to determine if a ToC causes two plants sharing resources to reproduce less successfully than two plants owning the equivalent amount of personal resources. We predict that plant root competition creates a ToC by increasing root mass while reducing reproductive mass. Our study uses ...
Getting In Deep, 2014 Colby College
Getting In Deep, Earl Smith
Cleaning up Johnson Pond required wading through a quagmire of regulations- and produced some surprising revelations.
Report On The Workshop For Life Detection In Samples From Mars, 2014 Portland State University
Report On The Workshop For Life Detection In Samples From Mars, Gerhard Kminek, Catherine Conley, Carlton C. Allen, Douglas H. Bartlett, David W. Beaty, Liane G. Benning, Rohit Bhartia, Penelope J. Boston, Caroline Duchaine, Jack D. Farmer, George J. Flynn, Daniel P. Glavin, Yuri Gorby, John E. Hallsworth, Rakesh Mogul, Duane Moser, P. Buford Price, Ruediger Pukall, David Fernandez-Remolar, Caroline L. Smith, Kenneth M. Stedman, Andrew Steele, Ramunas Stepanauskas, Henry Sun, Jorge L. Vago, Mary A. Voytek, Paul S. Weiss, Frances Westfall
Biology Faculty Publications and Presentations
The question of whether there is or was life on Mars has been one of the most pivotal since Schiaparellis’ telescopic observations of the red planet. With the advent of the space age, this question can be addressed directly by exploring the surface of Mars and by bringing samples to Earth for analysis. The latter, however, is not free of problems. Life can be found virtually everywhere on Earth. Hence the potential for contaminating the Mars samples and compromising their scientiﬁc integrity is not negligible. Conversely, if life is present in samples from Mars, this may represent a potential source ...
Across-Year Social Stability Shapes Network Structure In Wintering Migrant Sparrows, 2014 University of Nebraska - Lincoln
Across-Year Social Stability Shapes Network Structure In Wintering Migrant Sparrows, Daizaburo Shizuka, Alexis S. Chaine, Jennifer Anderson, Oscar Johnson, Inger Marie Laursen, Bruce E. Lyon
Faculty Publications in the Biological Sciences
Migratory birds often form flocks on their wintering grounds, but important details of social structure such as the patterns of association between individuals are virtually unknown. We analysed networks of co-membership in short-term flocks for wintering golden-crowned sparrows (Zonotrichia atricapilla) across three years and discovered social complexity unsuspected for migratory songbirds. The population was consistently clustered into distinct social communities within a relatively small area (~ 7 ha). Birds returned to the same community across years, with mortality and recruitment leading to some degree of turnover in membership. These spatiotemporal patterns were explained by the combination of space use and social ...
Stop Lion Hunting, 2014 University of Nebraska - Lincoln
Stop Lion Hunting, Paul Johnsgard
Paul Johnsgard Collection
According to my informal tally, at least seven mountain lions have so far been killed in Nebraska during 2014, as follows: 1 & 2: Two were killed on January 1 and 2, at the start of Nebraska's first hunting season. Both were killed by treeing the animals with dogs, then shooting them execution style. One was killed by a man who bought the permit ($13,500) at auction; the other by a teenager who won a Game & Park's fund -raising lottery. 3: An adult male was accidentally killed by a vehicle on February 1, in Sioux County. 4: An adult was accidentally killed by a cable entanglement in Custer County, February 16th. 5: An adult female was killed for sport on February 26 in Sioux County, ending the second phase of legal hunting, but leaving most of the state open for the rest of the ...
New Species Of Ctenomys Blainville 1826 (Rodentia: Ctenomyidae) From The Lowlands And Central Valleys Of Bolivia, 2014 University of Nebraska - Lincoln
New Species Of Ctenomys Blainville 1826 (Rodentia: Ctenomyidae) From The Lowlands And Central Valleys Of Bolivia, Scott Lyell Gardner, Jorge Salazar Bravo, Joseph A. Cook
Faculty Publications from the Harold W. Manter Laboratory of Parasitology
The genus Ctenomys Blainville 1826 is one of the most diverse of South American hystricognath rodents. Currently, nine species of tuco-tucos are reported from Bolivia, four at elevations above 2,000 m and five inhabiting the lowlands (< 1,000 m). In the present paper, morphology, karyology, and phylogenetic analyses of DNA sequences for a mitochondrial locus were used to assess the taxonomic status of specimens of Ctenomys from localities beyond the previously known ranges of these rodents in the departments of Chuquisaca, Cochabamba, Santa Cruz, and Tarija. Based on these analyses, we describe four new species in the genus Ctenomys, all apparently endemic to the country. In addition, we place Ctenomys goodfellowi Thomas 1921 in synonymy under C. boliviensis Waterhouse 1848 and confirm the presence of C. nattereri Wagner ...
Assessing Landscape Constraints On Species Abundance: Does The Neighborhood Limit Species Response To Local Habitat Conservation Programs?, 2014 University of Nebraska - Lincoln
Assessing Landscape Constraints On Species Abundance: Does The Neighborhood Limit Species Response To Local Habitat Conservation Programs?, Christopher F. Jorgensen, Larkin A. Powell, Jeffrey J. Lusk, Andrew A. Bishop, Joseph J. Fontaine
Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications
Landscapes in agricultural systems continue to undergo significant change, and the loss of biodiversity is an ever-increasing threat. Although habitat restoration is beneficial, management actions do not always result in the desired outcome. Managers must understand why management actions fail; yet, past studies have focused on assessing habitat attributes at a single spatial scale, and often fail to consider the importance of ecological mechanisms that act across spatial scales. We located survey sites across southern Nebraska, USA and conducted point counts to estimate Ring-necked Pheasant abundance, an economically important species to the region, while simultaneously quantifying landscape effects using a ...
Identifying The Role Of Non-Native Species In The Enhanced Trophic Transfer Of Mercury In The Food Web Of Lake Erie, A North American Great Lake, Kaylin M.S. Liznick
University of Western Ontario - Electronic Thesis and Dissertation Repository
Increasing mercury (Hg) concentrations in top predatory fish is concerning for human and wildlife health. This study examined the amount of Hg available to the food web of Lake Erie, and explored the role that two recently established non-native species, dreissenid mussels and round goby, have played in the trophic transfer of Hg to sport fish. A comprehensive sampling of total Hg (THg) and methylmercury (MeHg) within Lake Erie water, sediment and seston with high temporal and spatial resolution describes environmental concentrations. In addition, biotic THg and MeHg are quantified in benthic invertebrates and three fish species. A steep spatial ...
Variation In Habitat Thresholds: An Analysis Of Minimum Habitat Requirements Of North American Breeding Birds., 2014 The Graduate Center, CUNY
Variation In Habitat Thresholds: An Analysis Of Minimum Habitat Requirements Of North American Breeding Birds., Yntze Van Der Hoek
Dissertations and Theses, 2014-Present
Many species show dramatic changes in population extinction or persistence probability at particular habitat amounts. These `extinction thresholds' could be translated to conservation targets, under the condition that we can derive generalities. I investigated the level of variation in landscape-level habitat thresholds for a suite of North American, forest-associated, breeding birds. Records from Breeding Bird Atlases and the availability of remotely-sensed land cover data allowed me to compare habitat thresholds for 25 species across the states of Massachusetts, Michigan, New York, Ohio, Pennsylvania, and Vermont. I show that variation in thresholds is considerable (Chapter II, III), as thresholds range from ...
The Effect Of Population History On Hominoid Intraspecific Cranial Shape Diversity: Combining Population Genetic And 3d Geometric Morphometric Data, Julia Marie Zichello
Dissertations and Theses, 2014-Present
Cranial shape diversity within hominoids has been previously studied with the aim of understanding how levels of diversity in extant species compare with extinct hominin specimens. This dissertation addresses the question of why cranial shape diversity differs among extant hominoids. Levels of intraspecific cranial shape diversity are highly varied among hominoids. For example, Sumatran orangutan cranial shape diversity is more than twice that of all living humans. Here, the population history of each species, or sub-species, is considered as a force potentially structuring phenotypic variation. It is already well established that population history has shaped patterns of modern human cranial ...
Early Song Discrimination By Nestling Sparrows In The Wild, 2014 University of Nebraska - Lincoln
Early Song Discrimination By Nestling Sparrows In The Wild, Daizaburo Shizuka
Faculty Publications in the Biological Sciences
Songs play an important role in premating isolation in birds. However, when songs are learned, expe- rience with both conspecific and heterospecific songs in early life could lead to the development of both mixed songs and mixed preferences. One way that such learning errors can be prevented is if birds can discriminate between songs of different species prior to learning and preferentially memorize conspe- cific songs. Prior captive studies have shown that white-crowned sparrows, Zonotrichia leucophrys, are able to discriminate songs early in the process of song memorization, after about 10 days since hatching. I studied early song discrimination in ...
Photosynthetic Thermal Tolerance And Recovery To Short Duration Temperature Stress In Desert And Montane Plants: A Comparative Study, 2014 California Polytechnic State University
Photosynthetic Thermal Tolerance And Recovery To Short Duration Temperature Stress In Desert And Montane Plants: A Comparative Study, David William Gallagher
Master's Theses and Project Reports
- Climate change models predict an increase in frequency and amplitude of extreme weather events, including heat waves. To better predict how the composition and distribution of plant assemblages might respond to these changes in temperature, it is important to understand how species currently respond to these extremes. Photosynthetic thermal tolerance (T25)and photosynthetic recovery (RT25) were quantified in 27 species. We also studied the relationships between T25, RT25 and leaf mass per area (LMA). Leaf temperature was also monitored in the field.
- Leaves used in this study were collected from two distinct environments representing desert and ...
The Evolution Of Respiratory O2/No Reductases: An Out-Of-The-Phylogenetic-Box Perspective, 2014 University of Nebraska - Lincoln
The Evolution Of Respiratory O2/No Reductases: An Out-Of-The-Phylogenetic-Box Perspective, Anne-Lise Ducluzeau, Barbara Schoepp-Cothenet, Robert Van Lis, Frauke Baymann, Michael J. Russell, Wilfgang Nitschke
Biochemistry -- Faculty Publications
Complex life on our planet crucially depends on strong redox disequilibria afforded by the almost ubiquitous presence of highly oxidizing molecular oxygen. However, the history of O2-levels in the atmosphere is complex and prior to the Great Oxidation Event some 2.3 billion years ago, the amount of O2 in the biosphere is considered to have been extremely low as compared with present-day values. Therefore the evolutionary histories of life and of O2-levels are likely intricately intertwined. The obvious biological proxy for inferring the impact of changing O2-levels on life is the evolutionary ...
Privatization And Property In Biology, 2014 Washington University in St. Louis
Privatization And Property In Biology, Joan E. Strassmann, David C. Queller
Biology Faculty Publications
Organisms evolve to control, preserve, protect and invest in their own bodies. When they do likewise with external resources they privatize those resources and convert them into their own property. Property is a neglected topic in biology, although examples include territories, domiciles and nest structures, food caching, mate guarding, and the resources and partners in mutualisms. Property is important because it represents a solution to the tragedy of the commons; to the extent that an individual exerts long-term control of its property, it can use it prudently, and even invest in it. Resources most worth privatizing are often high in ...
Investigating Meter Scale Topographic Variation As A Factor Of Monterey Pine (Pinus Radiata) Growing Conditions At Kenneth Norris Rancho Marino Reserve, Cambria, Ca, 2014 California Polytechnic State University
Investigating Meter Scale Topographic Variation As A Factor Of Monterey Pine (Pinus Radiata) Growing Conditions At Kenneth Norris Rancho Marino Reserve, Cambria, Ca, William J. Meyst
Natural Resources Management and Environmental Sciences
Endemic Monterey pine (Pinus radiata) is limited to three locations in California due to its unique ecological requirements. This project was conducted to investigate spatial growth patterns ofMonterey pine over complex ground surfaces. The coastal hills of Rancho Marino Reserve, Cambria, were surveyed using four 150-m transects to quantify and record ground surface features and growing conditions ofMonterey pine. Changes in elevation of each transect were measured using an Abney level. Linear ground surfaces were found at 86% (344 of 400) of survey nodes. Convex ground surfaces were found at 10.5% of survey nodes (42 of 400). Of the ...
Conclusive Evidence Of Replication Of A Plant Virus In Honeybees Is Lacking, 2014 Iowa State University
Conclusive Evidence Of Replication Of A Plant Virus In Honeybees Is Lacking, W. Allen Miller, Jimena Carrillo-Tripp, Bryony C. Bonning, Adam G. Dolezal, Amy L. Toth
Entomology Publications and Papers
The recent article by Li et al. (1) lacks adequate evidence to support the authors’ assertion that a plant virus propagates or replicates in honeybees. Instead, it is possible that tobacco ringspot virus (TRSV) virions associate with the honeybee and parasitic Varroa mites in the absence of TRSV replication.
Black Bears (Ursus Americanus) As A Novel Potential Predator Of Agassiz’S Desert Tortoises (Gopherus Agassizii) At A California Wind Energy Facility, Jeffrey Lovich, David Delaney, Jessica Briggs, Mickey Agha, Meaghan Austin, Jason Reece
Bulletin of the Southern California Academy of Sciences
Black bears (Ursus americanus) and Agassiz’s desert tortoises (Gopherus agassizii) rarely interact due to substantial differences in their preferred habitats. In this paper we report a mother and cub black bear investigating an occupied tortoise burrow in a wind energy generation facility in the San Bernardino Mountains northwest of Palm Springs, California. While predation was not observed, bears are known to eat various turtle species around the world on an opportunistic basis. Given the proclivity of black bears to adopt specialized dietary opportunities on a learned, individual basis, the potential exists for predation on desert tortoises. Since black bears ...
Flight Initiation Distance Differs Between Populations Of Western Fence Lizards (Sceloporus Occidentalis) At A Rural And An Urban Site, Elizabeth K. Grolle, Michelle C. Lopez, Marina M. Gerson
Bulletin of the Southern California Academy of Sciences
Abstract.—Flight initiation distance (FID) is the distance to which a predator is permitted to approach before the prey initiates flight behavior. This can be influenced by factors including predator density and distance to cover. We measured flight initiation distances in two populations of Western fence lizards (Sceloporus occidentalis), one in a rural and one in an urban environment. Lizards at the rural site initiated flight at significantly longer distances than those at the urban site. These results support the prediction that lizard behavior can be influenced by differences in human exposure and predator recognition in their environments. Lizards develop ...