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Articles 3931 - 3960 of 4633

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Characterizing The Resident, Fermentative Microbial Consortium In The Hindgut Of The Temperate-Zone Herbivorous Fish, Hermosilla Azurea (Teleostei: Kyphosidae), Pat M. Fidopiastis, Daniel J. Bezdek, Michael H. Horn, Judith S. Kandel Jan 2006

Characterizing The Resident, Fermentative Microbial Consortium In The Hindgut Of The Temperate-Zone Herbivorous Fish, Hermosilla Azurea (Teleostei: Kyphosidae), Pat M. Fidopiastis, Daniel J. Bezdek, Michael H. Horn, Judith S. Kandel

Biological Sciences

The zebraperch, Hermosilla azurea Jenkins and Evermann, a warm-temperate marine fish species with a strictly macroalgal diet, has a relatively long digestive tract with an enlarged hindgut and an associated blind caecum (HC). In zebraperch sampled off Santa Catalina Island, California (33°19′42′′N; 118°18′37′′W) in years 1995 through 2001, direct cell counts, gut epithelium assessment of bacterial attachment, and short-chain fatty acid (SCFA) analyses verified that the zebraperch HC possesses a dense and morphologically diverse, fermentative microbiota. Bacterial cell counts and morphological diversity were significantly higher in HC contents compared to anterior gut regions, suggesting that microbial populations were growing along …

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An Ethogram Developed On Captive Eastern Coyotes Canis Latrans, Eric Strauss Jan 2006

An Ethogram Developed On Captive Eastern Coyotes Canis Latrans, Eric Strauss

Biology Faculty Works

We studied capture Eastern Coyotes (Canis latrans) from 27-585 days of age and compiled an ethogram on them. A total of 72247 15-sec samples were taken, amounting to 301 h of field time varying between 59.4-61.3 h per Coyote. A total of 540 behavioral patterns was observed amongst the 16 behaviour categories ranging from 9 (miscellaneous) to 72 (explore/investigate) action patterns per parent category. The 16 parent categories that we believed best described and appropriately sorted the behavioural actions were resting, sitting, sitting1, sitting2, standing, traveling, explore/investigating, hunting, feeding, infantile, greeting, self play, play initiating, playing, agonistic, and miscellaneous. Exploring …

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Coronary Heart Disease Risk Stratification In Full-Time Miami Valley Hospital Employees, Vicki K. Streng Jan 2006

Coronary Heart Disease Risk Stratification In Full-Time Miami Valley Hospital Employees, Vicki K. Streng

Browse all Theses and Dissertations

Heart disease is the number one killer in the United States (American Heart Association, 2005). The purpose of this study was to demonstrate the results of a twelve-week exercise program on coronary heart disease risk factors in full-time hospital employees. Methods: The participants were given cardiovascular, weight training, and flexibility recommendations to follow during a twelve-week period. The main heart disease risk factors measured before and after the completion of the exercise program were blood pressure, total cholesterol, HDL-cholesterol, and body mass index. The information was put into the Framingham Heart Score to estimate the participants’ 10-year risk of developing …

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Biomonitoring Organochlorine And Cholinesterase Inhibiting Insecticide In Eastern Iowa Streams, Matthew Thomas Fisher Jan 2006

Biomonitoring Organochlorine And Cholinesterase Inhibiting Insecticide In Eastern Iowa Streams, Matthew Thomas Fisher

Dissertations and Theses @ UNI

The four chapters in this thesis provide results from five separate investigations. Chapter One describes Isonychia bicolor acetylcholinesterase (AChE) activity in Northeast Iowa rivers. During 2002 and 2003 insects were collected from 10 sites during May, July and September, three sites on the Volga River were sampled weekly during May and June and one Cedar River site was sampled monthly. Also, in 2003, three sites on the Upper Iowa were sampled weekly in May and June. Sampling often sites yielded few discernable trends, however decreasing AChE activity from upstream to downstream sites was apparent on several occasions on the Volga …

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Beaver Home Ranges And Movement Patterns On The Embarras River Watershed In East Central Illinois, Randall P. Havens Jan 2006

Beaver Home Ranges And Movement Patterns On The Embarras River Watershed In East Central Illinois, Randall P. Havens

Masters Theses

The beaver (Castor canadensis) is an ecologically and economically important species that has been much studied and exploited during its long association with humans (Bradt 1938, Hodgdon 1978, Novak 1987, Muller-Schwartze and Schulte 1999). Beavers have been described as ecosystem engineers and a keystone species because of their ability to physically modify, maintain, or create wetlands thereby controlling resources used by other organisms and altering the physical state of the environment (Jones et al. 1994). They are capable of impacting the local environment through dam construction, selective tree harvest, and den construction. For example, beaver dams impact stream hydrology, nutrient …

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Impaired Glutamate Transport In A Mouse Model Of Tau Pathology In Astrocytes, Deepa V. Dabir Jan 2006

Impaired Glutamate Transport In A Mouse Model Of Tau Pathology In Astrocytes, Deepa V. Dabir

Biology Faculty Works

Filamentous tau inclusions in neurons and glia are neuropathological hallmarks of tauopathies. The discovery of microtubule-associated protein tau gene mutations that are pathogenic for a heterogenous group of neurodegenerative disorders, called frontotemporal dementia and parkinsonism linked to chromosome-17 (FTDP-17), directly implicate tau abnormalities in the onset/progression of disease. Although the role of tau pathology in neurons in disease pathogenesis is well accepted, the contribution of glial pathology is essentially unknown. We recently generated a transgenic (Tg) mouse model of tau pathology in astrocytes by expressing the human tau protein under the control of the glial fibrillary acidic protein (GFAP) promoter. …

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Feather Mites Are Positively Associated With Daily Survival In Cliff Swallows, Charles R. Brown, Kathleen R. Brazeal, Stephanie A. Strickler, Mary Bomberger Brown Jan 2006

Feather Mites Are Positively Associated With Daily Survival In Cliff Swallows, Charles R. Brown, Kathleen R. Brazeal, Stephanie A. Strickler, Mary Bomberger Brown

School of Biological Sciences: Faculty Publications

Feather mites (Acari: Astigmata) have been reported to be parasitic, commensal, and even mutualis-tic on the birds that serve as their hosts. We investigated whether there was a relationship between number of feather mites (Pteronyssoides obscurus (Berlese, 1885)) on the wing and daily survival of cliff swallows (Petrochelidon pyrrhonota (Vieillot, 1817)) during the breeding season at 12 nesting colonies in Nebraska in 2005. Survival of birds with known mite loads was monitored by mark–recapture, and survival models with and without a linear effect of mites were compared with the program MARK. For adult swallows, mites were positively associated …

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Foraging Behavior And Success Of Herons And Egrets In Natural And Artificial Wetlands, Henry Dewayne Mincey Jan 2006

Foraging Behavior And Success Of Herons And Egrets In Natural And Artificial Wetlands, Henry Dewayne Mincey

College of Graduate Studies: Theses & Dissertations

The southeastern United States has approximately 13.2 million hectares of wetland habitat, but these sensitive areas are subject to loss and degradation from draining and development. The effects, both positive and negative, that manipulation of these wetlands have on wildlife is still under study. In particular, there is a need to know whether artificial (mitigated) wetlands can serve as an appropriate substitute for the loss of natural wetlands. Therefore, I quantified the foraging behavior of herons and egrets (species that are dependent on wetlands for food) in natural and artificial wetlands in southeastern coastal Georgia and southern coastal South Carolina. …

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Limits Of Temperature Tolerance Of Leishmania Enriettii And Leishmania Hertigi In A Real-Time Pcr Assay, Christina Salinas Dec 2005

Limits Of Temperature Tolerance Of Leishmania Enriettii And Leishmania Hertigi In A Real-Time Pcr Assay, Christina Salinas

Theses & Dissertations

Protozoans of the genus Leishmania are intracellular parasites found across five continents. They cycle between a promastigote form inside the digestive tracts of blood-feeding female sand flies and an amastigote form within mammalian host macrophages. Temperature is an important factor that must be defeated in order for the parasites' survival and continuance. This paper studies the limits of temperature tolerance by Leishmania enriettii and Leishmania hertigi. It was hypothesized that a correlation would exist between the limits of temperature tolerance to body temperature of their host. I explored growth characteristics at 21,27,29, 33, 35, 37, and 39° C. It was …

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Bateman Gradients In Field And Laboratory Studies: A Cautionary Tale, Patricia Parker, Zuleyma Tang-Martinez Nov 2005

Bateman Gradients In Field And Laboratory Studies: A Cautionary Tale, Patricia Parker, Zuleyma Tang-Martinez

Biology Department Faculty Works

Since tools of molecular genetics became readily available, our understanding of bird mating systems has undergone a revolution. The majority of passerine species investigated are socially monogamous, but have been shown to be genetically polygamous. Data sets from natural populations of juncos suggest that multiple mating by females results in a sexual selection gradient as steep for females as for males (a result that does not support Bateman's predictions). However, in males, fitness is enhanced directly through fertilization success with multiple matings; in females fitness benefits may be enhanced immediately through direct access to food, protection against predators, or other …

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Rapid Senescence In Pacific Salmon, Yolanda E. Morbey, Chad Brassil, Andrew P. Hendry Nov 2005

Rapid Senescence In Pacific Salmon, Yolanda E. Morbey, Chad Brassil, Andrew P. Hendry

School of Biological Sciences: Faculty Publications

Any useful evolutionary theory of senescence must be able to explain variation within and among natural populations and species. This requires a careful characterization of age-specific mortality rates in nature as well as the intrinsic and extrinsic factors that influence these rates. We perform this task for two populations of semelparous Pacific salmon. During the breeding season, estimated daily mortality rates increased from 0 to 0.2–0.5 (depending on the year) over the course of several weeks. Early-arriving individuals had a later onset and/or a lower rate of senescence in each breeding season, consistent with adaptive expectations based on temporal variation …

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Modulation Of Tyramine Signaling By Osmolality In An Insect Secretory Epithelium, Edward M. Blumenthal Nov 2005

Modulation Of Tyramine Signaling By Osmolality In An Insect Secretory Epithelium, Edward M. Blumenthal

Biological Sciences Faculty Research and Publications

The control of water balance in multicellular organisms depends on absorptive and secretory processes across epithelia. This study concerns the effects of osmolality on the function of the Malpighian tubules (MTs), a major component of the insect excretory system. Previous work has shown that the biogenic amine tyramine increases transepithelial chloride conductance and urine secretion in Drosophila MTs. This study demonstrates that the response of MTs to tyramine, as measured by the depolarization of the transepithelial potential (TEP), is modulated by the osmolality of the surrounding medium. An increase in osmolality caused decreased tyramine sensitivity, whereas a decrease in osmolality …

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Carotenoid Availability Affects The Development Of A Colour-Based Mate Preference And The Sensory Bias To Which It Is Genetically Linked, Gregory F. Grether, Gita R. Kolluru, F. Helen Rodd, Jennifer De La Cerda, Kaori Shimazaki Oct 2005

Carotenoid Availability Affects The Development Of A Colour-Based Mate Preference And The Sensory Bias To Which It Is Genetically Linked, Gregory F. Grether, Gita R. Kolluru, F. Helen Rodd, Jennifer De La Cerda, Kaori Shimazaki

Biological Sciences

Regardless of their origins, mate preferences should, in theory, be shaped by their benefits in a mating context. Here we show that the female preference for carotenoid colouration in guppies (Poecilia reticulata) exhibits a phenotypically plastic response to carotenoid availability, confirming a key prediction of sexual selection theory. Earlier work indicated that this mate preference is genetically linked to, and may be derived from, a sensory bias that occurs in both sexes: attraction to orange objects. The original function of this sensory bias is unknown, but it may help guppies find orange-coloured fruits in the rainforest streams of …

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Evolution Of Sexual Dimorphism And Male Dimorphism In The Expression Of Beetle Horns: Phylogenetic Evidence For Modularity, Evolutionary Lability, And Constraint, Douglas J. Emlen, John Hunt, Leigh W. Simmons Oct 2005

Evolution Of Sexual Dimorphism And Male Dimorphism In The Expression Of Beetle Horns: Phylogenetic Evidence For Modularity, Evolutionary Lability, And Constraint, Douglas J. Emlen, John Hunt, Leigh W. Simmons

Biological Sciences Faculty Publications

Beetle horns are enlarged outgrowths of the head or thorax that are used as weapons in contests over access to mates. Horn development is typically confined to males (sexual dimorphism) and often only to the largest males (male dimorphism). Both types of dimorphism result from endocrine threshold mechanisms that coordinate cell proliferation near the end of the larval period. Here, we map the presence/absence of each type of dimorphism onto a recent phylogeny for the genus Onthophagits (Coleoptera: Scarabaeidae) to explore how horn development has changed over time. Our results provide empirical support for several recent predictions regarding the evolutionary …

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Fish Consumption Patterns Of Populations In Vicinities Of Lake Kastoria And Lake Pamvotis, Greece, Eugene G. Maurakis, David V. Grimes, Dimitra Bobori Oct 2005

Fish Consumption Patterns Of Populations In Vicinities Of Lake Kastoria And Lake Pamvotis, Greece, Eugene G. Maurakis, David V. Grimes, Dimitra Bobori

Virginia Journal of Science

Objectives are to establish fish consumption patterns of populations in vicinities of two lakes (Kastoria and Pamvotis) in Greece for use in the assessment of risks associated with consumption of fishes in these agri-chemically impaired lakes. Parameters measured were demographics (i.e., gender, age, weight, education level, occupation, residency), freshwater fish eating frequency, species and sizes of fishes consumed, and fish consumption habits [i.e., quantity, parts, and preparation method). All annual mean site-specific consumption rates of the four gender-age class sub-populations surveyed in vicinity of Lake Kastoria (avg. range= 0.103-0.29 kg/day) exceed those of Greece (0.066 kg/day), EU (0.068 kg/day), Spain …

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Online Dictionary Of Invertebrate Zoology: F, Mary Ann Basinger Maggenti, Armand R. Maggenti, Scott L. Gardner Sep 2005

Online Dictionary Of Invertebrate Zoology: F, Mary Ann Basinger Maggenti, Armand R. Maggenti, Scott L. Gardner

Armand R. Maggenti Online Dictionary of Invertebrate Zoology

face facet facette facetted facial facialium facies facio-orbital factor facultative faeces Fahrenholz's falcate falces falciform falciger falcis falculate falsadentes false falx famulus fan fang farctate farinaceous fascia fasciate fascicle fasciculus fasciole fascio-maculata fascio-punctate fastening fastigiate fastigium fat fate fauces fauna faunal faveolate feces fecula fecundate fecundity feedback feeder feeding feeler feet felt female femoro-alary femorogenu femorotibial femur fenestra fenestrate fenestration fenestrella fenestrule fente feral ferment fermentation ferreous ferruginous ferrule fertile fertility fertilization fertilizin festivus festoon festoons fetid fiber fibril fibrillar fibrin fibrinogen fibrocyte fibroin fibroplasm fibrous fibula fide filament filamentary filaria filariform filate filator file filial filiation filibranch filicornia filiform …

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Online Dictionary Of Invertebrate Zoology: G, Mary Ann Basinger Maggenti, Armand R. Maggenti, Scott L. Gardner Sep 2005

Online Dictionary Of Invertebrate Zoology: G, Mary Ann Basinger Maggenti, Armand R. Maggenti, Scott L. Gardner

Armand R. Maggenti Online Dictionary of Invertebrate Zoology

galea gallery gallicola gallicolae gallicolous galliphagous galvanotaxis galvanotropism gametangiogamy gametangium gamete gametocyte gametogamy gametogenesis gametogenetic gametogeny gametogonium gametogony gametotoky gamma gamobium gamodeme gamogenesis gamogonic gamogony gamones gamophase ganglia gangliate ganglion ganglionic gap gaper gaping gas gaseous gaster gasterostome gasterotheca gastraea gastraeum gastral gastralia gastric gastrilegous gastrocoele gastrocoelus gastrodermis gastro-ileal gastrolith gastroorbital Gastropoda gastropods gastropores Gastrotricha gastrotrichs gastrovascular gastrozooid gastrula gastrular gathering Gause's gelatigenous gelatin gelatine gelatinous geminate gemma gemmate gemmation gemmipara gemmipares gemmule gemmulostasin gena genacerore genae genal genaponta genatasinus gene genera generalized generation generative generitype generotype Gene's genesiology genetic genetics genic genicular geniculate genital genitalia genitointestinal genocline genocopy genodeme …

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Online Dictionary Of Invertebrate Zoology: N, Mary Ann Basinger Maggenti, Armand R. Maggenti, Scott L. Gardner Sep 2005

Online Dictionary Of Invertebrate Zoology: N, Mary Ann Basinger Maggenti, Armand R. Maggenti, Scott L. Gardner

Armand R. Maggenti Online Dictionary of Invertebrate Zoology

nacre nacreous naiad nail naked nanism nanoid nanitic worker nanometer nanoplankton nanozooid narcosis nasale nascent naso Nassanoff's gland Nassanov's gland Nassanov's gland nasus nasute natal natality rate natant natatory natatory lamellae nates naticid naticiform native natural classification artificial classification natural decrease natural increase natural group natural increase natural requeening supersedure natural selection naupliar eye nauplius eye naupliiform nauplius eye nauplius larva nautilicone nautiliform nautiloid nautiloid navicular neala neallotype neanic neap Nearctic neascus larva nebulous neck neck organ nuchal organ necrobiosis necrocytosis necrophagous necrophoresis necrophoric behavior necrosis necrotize nectar nectobenthic nectocalyx nectophore nectochaeta larva necton nekton nectophore pneumatophore nectopod nectosome nectozooid …

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Online Dictionary Of Invertebrate Zoology: H, Mary Ann Basinger Maggenti, Armand R. Maggenti, Scott L. Gardner Sep 2005

Online Dictionary Of Invertebrate Zoology: H, Mary Ann Basinger Maggenti, Armand R. Maggenti, Scott L. Gardner

Armand R. Maggenti Online Dictionary of Invertebrate Zoology

habitat habitude habroderes hackled haem haematodocha haemocoele haemocoelous haemocyte haemolymph haemolysis hae¬mopoietic haemostatic haemoxanthine haft hair haliotoid Haller's halmatometamorphosis halocline halophile halter halteres hamabiosis hamate hamatype hami hamiform hammock hampe hamula hamular hamulohalterae hamulus hamus Hancock's hapaloderes haplobiont haplo-diploidy haploid haplometrosis haplometrotic haploneme haploneural haplont haplophase haplosis haptolachus haptomeri haptomerum haptor Hardy-Weinberg harmonic harmosis harpago harpagones harpes harpoon hastate hastisetae hatching haustellate haustellum haustrulum Hautkorper Hayes' H-band head head-fans heart heautotype hectocotylus heel height heli helical helices helicocone heliophil heliophilic heliophilous heliophobic heliotaxis heliotropism helix helmet helminth helminthiasis helminthic Helminthology helocerous helotism helus hem hemal hemapoiesis hematacyte hematal hematocyte hematodocha …

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Online Dictionary Of Invertebrate Zoology: S, Mary Ann Basinger Maggenti, Armand R. Maggenti, Scott L. Gardner Sep 2005

Online Dictionary Of Invertebrate Zoology: S, Mary Ann Basinger Maggenti, Armand R. Maggenti, Scott L. Gardner

Armand R. Maggenti Online Dictionary of Invertebrate Zoology

sabulose sabulous sac saccate saccharobiose sacciform saccule saccus sacoglossa saddle Saefftigen's sagittae sagittocysts saliva salivarium salivary saltation Saltatoria saltatory saltigrade sanguinivorous sanidasters sapphirine saprobe saprobiont saprobiotic saprophagous saprophyte saprozite saprozoic saprozoite sarcobelum sarcode sarcolemma sarcolysis sarcomere sarcomeric sarcophagous sarcoplasm sarcoplasmic sarcosomes sarcostyle sarcotheca sarothrum saxicavous saxicolous scabellum scabrous scalariform scalaroid scalids scalpellum scalpriform scansorial scape scaphe scaphiform scaphium scaphocerite scaphognathite scaphoid Scaphopoda scapula scapus scarabaeiform scarabaeoid scarified scariose scatophagous scavenger scent sceptrules schemochrome schistosomula schizeckenosy schizocele schizochroal schizocoel schizodont schizogamy schizogenesis schizolophe schizopeltid schizopod schizorhyses Schmidt's Schwann scissorial scissure sclerification sclerite scleroblasts sclerocyte sclerophagous sclerosepta sclerotic scoleces scolecid scoleciform scolecoid …

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Online Dictionary Of Invertebrate Zoology: T, Mary Ann Basinger Maggenti, Armand R. Maggenti, Scott L. Gardner Sep 2005

Online Dictionary Of Invertebrate Zoology: T, Mary Ann Basinger Maggenti, Armand R. Maggenti, Scott L. Gardner

Armand R. Maggenti Online Dictionary of Invertebrate Zoology

tabula tabular tachyauxesis tachyblastic tachygen tachygenesis tachytelic tactic tactile tactoreceptors taenia taeniate taenidium taenioglossate tagma tagmata tagmosis tail tailfan Takakura's talon talus tandem tangent tangoreceptor tanylobous tapetal tapetum tapinoma-odor Tardigrada tardigrades tarsal tarsation tarsite tarsomere tarsungulus tarsus taste tautonomy tautonym taxa taxes taxis taxis taxodont taxometrics taxon taxonomic taxonomist taxonomy tectiform tectostracum tectum teeth teges tegillum tegmen tegmentum tegula tegular tegulum tegumen tegument tegumentary tela telaform telamon telegonic teleiochrysalis telenchium teleoconch teleodont teleology teleotrocha telepod telescope telescopic teletrophic telioderma teliophan telmophage telocentric telodendria telofemur telogonic telolecithal telomitic telophase telophragma telopod telopodite telorhabdions telosonic telostome telosynapsis telosyndesis telotarsus telotaxis telotroch telson …

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Online Dictionary Of Invertebrate Zoology: W X Y Z, Mary Ann Basinger Maggenti, Armand R. Maggenti, Scott L. Gardner Sep 2005

Online Dictionary Of Invertebrate Zoology: W X Y Z, Mary Ann Basinger Maggenti, Armand R. Maggenti, Scott L. Gardner

Armand R. Maggenti Online Dictionary of Invertebrate Zoology

Wagener's larva waggle dance walking leg pereopod wall warm-blooded homoiothermal warning coloration sematic aposematic pseudaposematic wart verruca tubercle water pore hydropore Waterston's organ water vascular system wax wax gland wax layer wax-plate wax scale web weighting Weismann's ring ring gland wheel organ white body Hensen's gland white cuticle yellow cuticle wholemount whorl width wild type wing ala winter egg summer egg With's organs workers worker jelly xanthic xanthophyll xanthopterin xanthopterine X-chromosomes xenagones xenic axenic polyxenic synxenic trix¬enic xenobiosis xenoecic xenogamy cross-fertilization xenogenesis heterogenesis xenomone allelochemic xenomorphism xenoparasite xerarch succession xeric xerophilous xerophobous xerosere lithosere hydrosere xerothermic fauna xiphidiocercaria microcotylate cer¬caria …

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Evolution Of Morphological Integration: Developmental Accommodation Of Stress-Induced Variation, Alexander V. Badyaev, Kerry R. Foresman, Rebecca L. Young Sep 2005

Evolution Of Morphological Integration: Developmental Accommodation Of Stress-Induced Variation, Alexander V. Badyaev, Kerry R. Foresman, Rebecca L. Young

Biological Sciences Faculty Publications

Extreme environmental change during growth often results in an increase in developmental abnormalities in the morphology of an organism. The evolutionary significance of such stress-induced variation depends on the recurrence of a stressor and on the degree to which developmental errors can be accommodated by an organism's ontogeny without significant loss of function. We subjected populations of four species of soricid shrews to an extreme environment during growth and measured changes in the patterns of integration and accommodation of stress-induced developmental errors in a complex of mandibular traits. Adults that grew under an extreme environment had lower integration of morphological …

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Geographical Distributions, Relative Abundance And Coexistence Of Drosophila Aldrichi And Drosophila Buzzatii In Australia, J. S.F. Barker, Robert A. Krebs, H. I. Davies Aug 2005

Geographical Distributions, Relative Abundance And Coexistence Of Drosophila Aldrichi And Drosophila Buzzatii In Australia, J. S.F. Barker, Robert A. Krebs, H. I. Davies

Biological, Geological, and Environmental Faculty Publications

Climatic data and collection records for the cactophilic Drosophila aldrichi and Drosophila buzzatii for 97 localities were used to examine the effects of geographical location, season, host plant species and climatic factors on their range and relative abundance. Temporal variation in relative abundance was assessed from monthly collections over 4 years at one locality. Effects of weather variables over the 28 days before each collection were examined. A generalized linear model of the spatial data showed significant geographical variation in relative abundance, and significant climatic effects, with the proportion of D. aldrichi higher in the warm season, and increasing as …

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Elevated Levels Of Trace Elements In Cores Of Otoliths And Their Potential For Use As Natural Tags, Benjamin I. Ruttenberg, Scott L. Hamilton, Michael J.H. Hickford, Georges L. Paradis, Michael S. Sheehy, Julie D. Standish, Ofer Ben-Tzvi, Robert R. Warner Aug 2005

Elevated Levels Of Trace Elements In Cores Of Otoliths And Their Potential For Use As Natural Tags, Benjamin I. Ruttenberg, Scott L. Hamilton, Michael J.H. Hickford, Georges L. Paradis, Michael S. Sheehy, Julie D. Standish, Ofer Ben-Tzvi, Robert R. Warner

Biological Sciences

Variation in the chemical composition of fish otoliths has been used in recent years to address a range of ecological questions, including levels of stock mixing, variation in habitat use, and rates of larval exchange. While some of these questions have been answered with varying success, the degree to which discrete populations are connected via larval exchange remains unknown. To identify larval sources using natural variation in otolith chemistry, we must distinguish and measure the chemical composition of the otolith core, the portion of the otolith formed at the spawning site. Using laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS), …

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Human Activity Mediates A Trophic Cascade Caused By Wolves, Mark Hebblewhite, Clifford A. White, Clifford G. Nietvelt, John A. Mckenzie, Tomas E. Hurd, John M. Fryxell, Suzanne E. Bayley, Paul C. Paquet Aug 2005

Human Activity Mediates A Trophic Cascade Caused By Wolves, Mark Hebblewhite, Clifford A. White, Clifford G. Nietvelt, John A. Mckenzie, Tomas E. Hurd, John M. Fryxell, Suzanne E. Bayley, Paul C. Paquet

Biological Sciences Faculty Publications

Experimental evidence of trophic cascades initiated by large vertebrate predators is rare in terrestrial ecosystems. A serendipitous natural experiment provided an opportunity to test the trophic cascade hypothesis for wolves (Canis lupus) in Banff National Park, Canada. The first wolf pack recolonized the Bow Valley of Banff National Park in 1986. High human activity partially excluded wolves from one area of the Bow Valley (low-wolf area), whereas wolves made full use of an adjacent area (high-wolf area). We investigated the effects of differential wolf predation between these two areas on elk (Cervus elaphus) population density, adult …

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Ecotypic Variation In Phosphorus Acquisition Mechanisms Within Marine Picocyanobacteria, Lisa Moore Phd, M. Ostrowski, D. J. Scanlan, K. Feren, T. Sweetsir Jun 2005

Ecotypic Variation In Phosphorus Acquisition Mechanisms Within Marine Picocyanobacteria, Lisa Moore Phd, M. Ostrowski, D. J. Scanlan, K. Feren, T. Sweetsir

Faculty Publications

Prochlorococcus and Synechococcus are major prokaryotic primary producers in the oligotrophic oceans that may be affected by the climate-related increases in nitrogen fixation and subsequent phosphorus (P) limitation in some parts of the oceans. Evidence that Prochlorococcus populations in the North Pacific subtropical gyre (NPSG) have increased over the past decades, possibly due to having a competitive advantage under conditions of P limitation, suggests aspects of their Pphysiology that are important for dictating their in situ success. Here, we compared the physiology of P acquisition and response to P stress (indicated by alkaline phosphatase activity, APA) among isolates of Prochlorococcus …

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Effects Of Food Supplementation On The Physiological Ecology Of Female Western Diamond‐Backed Rattlesnakes (Crotalus Atrox), Emily N. Taylor, Michael A. Malawy, Dawn M. Browning, Shea V. Lemar, Dale F. Denardo Jun 2005

Effects Of Food Supplementation On The Physiological Ecology Of Female Western Diamond‐Backed Rattlesnakes (Crotalus Atrox), Emily N. Taylor, Michael A. Malawy, Dawn M. Browning, Shea V. Lemar, Dale F. Denardo

Biological Sciences

Food availability is an important factor in the life histories of organisms because it is often limiting and thus can affect growth, mass change, reproduction, and behaviors such as thermoregulation, locomotion, and mating. Experimental studies in natural settings allow researchers to examine the effects of food on these parameters while animals are free to behave naturally. The wide variation among organisms in energy demands and among environmental food resources suggest that responses to changes in food availability may vary among organisms. Since most supplemental feeding field experiments have been conducted on species with high energy demands, we conducted a supplemental …

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Interspecific Divergence In Foliar Nutrient Dynamics And Stem Growth In A Temperate Forest In Response To Chronic Nitrogen Inputs, Jeffrey D. May, Sarah Beth Burdette, Frank S. Gilliam, Mary Beth Adams May 2005

Interspecific Divergence In Foliar Nutrient Dynamics And Stem Growth In A Temperate Forest In Response To Chronic Nitrogen Inputs, Jeffrey D. May, Sarah Beth Burdette, Frank S. Gilliam, Mary Beth Adams

Biological Sciences Faculty Research

We studied the effects of excessive nitrogen (N) fertilization on foliar nutrient dynamics and stem growth in three important tree species in a mixed-deciduous forest. Stem diameter growth, foliar N concentrations, nitrogen–phosphorus (N/P) ratios, and nutrient resorption were determined for Acer rubrum L. (ACRU), Liriodendron tulipifera L. (LITU), and Prunus serotina Ehrh. (PRSE) on two 30-year-old watersheds at the Fernow Experimental Forest, West Virginia, USA: WS3, fertilized annually with 35 kg ammonium sulfate·ha-1 since 1989, and WS7, an untreated control watershed. In an earlier (1992) study, foliar N concentrations of all three species averaged 11% higher in WS3 than …

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Deer-Vehicle Crash Patterns Across Ecoregions In Michigan, Krishnan Sudharsan, Shawn J. Riley, Brent A. Rudolph, Brian A. Maurer May 2005

Deer-Vehicle Crash Patterns Across Ecoregions In Michigan, Krishnan Sudharsan, Shawn J. Riley, Brent A. Rudolph, Brian A. Maurer

Wildlife Damage Management Conference

Deer-vehicle collisions (DVCs) impact the economic and social well being of humans. We examined large-scale patterns behind DVCs across 3 ecoregions: Southern Lower Peninsula (SLP), Northern Lower Peninsula (NLP), and Upper Peninsula (UP) in Michigan. A 3 component conceptual model of DVCs with drivers, deer, and a landscape was the framework of analysis. The conceptual model was parameterized into a parsimonious mathematical model. The dependent variable was DVCs by county by ecoregion and the independent variables were percent forest cover, percent crop cover, mean annual vehicle miles traveled (VMT), and mean deer density index (DDI) by county. A discriminant function …

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