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1998

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Articles 6931 - 6960 of 7597

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Estimates Of Annual Survival Probabilities For Adult Florida Manatees (Trichechus Manatus Latirostris), C. A. Langtimm, T. J. O'Shea, R. Pradel, C. A. Beck Jan 1998

Estimates Of Annual Survival Probabilities For Adult Florida Manatees (Trichechus Manatus Latirostris), C. A. Langtimm, T. J. O'Shea, R. Pradel, C. A. Beck

United States Geological Survey: Staff Publications

The population dynamics of large, long-lived mammals are particularly sensitive to changes in adult survival. Understanding factors affecting survival patterns is therefore critical for developing and testing theories of population dynamics and for developing management strategies aimed at preventing declines or extinction in such taxa. Few studies have used modern analytical approaches for analyzing variation and testing hypotheses about survival probabilities in large mammals. This paper reports a detailed analysis of annual adult survival in the Florida manatee (Trichechus manatus latirostris), an endangered marine mammal, based on a mark-recapture approach. Natural and boat- inflicted scars distinctively "marked" individual …

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The ‘‘Foliage Is The Fruit’’ Hypothesis: Complex Adaptations In Buffalograss (Buchloe Dactyloides), John Ortmann, Walter H. Schacht, James L. Stubbendieck, Dennis R. Brink Jan 1998

The ‘‘Foliage Is The Fruit’’ Hypothesis: Complex Adaptations In Buffalograss (Buchloe Dactyloides), John Ortmann, Walter H. Schacht, James L. Stubbendieck, Dennis R. Brink

Department of Agronomy and Horticulture: Faculty Publications

Buffalograss (Buchloe dactyloides) has been described as an excellent fit for Janzen’s ‘‘Foliage is the Fruit’’ (FF) hypothesis, which suggests that large grazing animals ingest and later disperse seeds of some herbs when consuming their foliage. We tested this hypothesis by feeding buffalograss burs and legume seeds to ruminally fistulated beef steers. Our objectives were to determine (1) rumen residence times of buffalograss burs, free buffalograss caryopses and legume seeds; (2) total tract residence times for the three types of propagules; (3) percentage propagule survival after passage and (4) germinability of fed and unfed burs and caryopses. Bur …

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Expression Of A Heterologous Polypeptide In Mammary Tissue Of Transgenic Non-Human Mammals Using Along Whey Acdic Protein Promoter, Henryk Lubon, William N. Drohan, Lother Hennighausen Jan 1998

Expression Of A Heterologous Polypeptide In Mammary Tissue Of Transgenic Non-Human Mammals Using Along Whey Acdic Protein Promoter, Henryk Lubon, William N. Drohan, Lother Hennighausen

Department of Chemical and Biomolecular Engineering: Faculty Publications

Heterologous polypeptides are produced in the milk of transgenic non-human mammals by the expression of a Stably integrated DNA sequence containing the long whey acidic protein promoter operably linked to a DNA sequence encoding a heterologous polypeptide and a signal Sequence. The transgenic non-human mammals of the present invention are produced by introducing this DNA sequence Such that the DNA sequence is stably integrated into the DNA of germ line cells of the mature mammal and inherited in normal Mendelian fashion. A representative heterologous polypeptide is protein C.

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Growth Traits Among Sorghum Genotypes In Response To Aluminum, J. H. Bernal, R. B. Clark Jan 1998

Growth Traits Among Sorghum Genotypes In Response To Aluminum, J. H. Bernal, R. B. Clark

Department of Agronomy and Horticulture: Faculty Publications

Aluminum (Al) has many detrimental effects on plant growth, and shoots and roots are normally affected differently. A study was conducted to determine differences among sorghum [Sorghum bicolor (L.) Moench] genotypes with broad genetic backgrounds for growth traits of plants grown at 0,200,400,600, and 800 uM Al in nutrient solutions (pH 4.0). Genotypes were categorized into "Al-sensitive", "intermediate Al-tolerant", "Al-tolerant", and SC 283 (an Al-tolerant standard). As Al increased, shoot and root dry matter (DM), net main axis root length (NMARL), and total root length (TRL) became lower than controls (0 Al). Aluminum toxicity and/or nutrient deficiency symptoms become …

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Design Of Tapered Augers For Uniform Unloading Particulate Material From Rectangular Cross-Section Containers, M. S. Burr, Michael F. Kocher, David D. Jones Jan 1998

Design Of Tapered Augers For Uniform Unloading Particulate Material From Rectangular Cross-Section Containers, M. S. Burr, Michael F. Kocher, David D. Jones

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The design equation for an auger to provide uniform unloading of particulate material from a container with a rectangular cross-section (Jones and Kocher, 1995) was revised to account for the minimum flighting height that could effectively unload particles with a known average smallest diameter. A minimum flighting height that was about 64% of the average smallest diameter of the particles was experimentally determined to obtain mean slopes of the top surface of the material not significantly different from zero for screened soybeans. A linear taper that best fit the square root curve for the inside diameter of the auger was …

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Matrix-Enhanced Calibration Procedure For Multivariate Calibration Models With Near-Infrared Spectra, Mark R. Riley, Mark A. Arnold, David W. Murhammer Jan 1998

Matrix-Enhanced Calibration Procedure For Multivariate Calibration Models With Near-Infrared Spectra, Mark R. Riley, Mark A. Arnold, David W. Murhammer

Department of Agricultural and Biological Systems Engineering: Faculty Publications

A novel method is introduced for developing calibration models for the spectroscopic measurement of chemical concentrations in an aqueous environment. To demonstrate this matrix-enhanced calibration procedure, we developed calibration models to quantitate glucose and glutamine concentrations in an insect cell culture medium that is a complex mixture of more than 20 components, with three components that manifest significant concentration changes. Accurate calibration models were generated for glucose and glutamine by using a calibration data set composed of 60 samples containing the analytes dissolved in an aqueous buffer along with as few as two samples of the analytes dissolved in culture …

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The Ecology And Evolution Of Spatial Memory In Corvids Of The Southwestern Usa: The Perplexing Pinyon Jay, Russell P. Balda, Alan Kamil Jan 1998

The Ecology And Evolution Of Spatial Memory In Corvids Of The Southwestern Usa: The Perplexing Pinyon Jay, Russell P. Balda, Alan Kamil

Papers in Behavior in Biological Sciences

The corvids of the southwest possess many adaptations for the harvest, transport, caching and recovery of pine seeds. However, there is a large degree of between-species variation in the distribution of these traits. These corvids have a well-accepted phylogeny (Hope, 1989), live within close proximity to one another and have relatively well-known natural histories. They therefore present an excellent opportunity to apply the comparative method (Kamil, 1988) to the study of these species differences (Balda et al., 1997). The comparative method for the study of adaptation and evolution of behavioral traits begins with a careful study of the natural histories …

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On The Proper Definition Of Cognitive Ethology, Alan Kamil Jan 1998

On The Proper Definition Of Cognitive Ethology, Alan Kamil

Papers in Behavior in Biological Sciences

The last 20-30 years have seen two “scientific revolutions” in the study of animal behavior: the cognitive revolution that originated in psychology, and the Darwinian, behavioral ecology revolution that originated in biology. Among psychologists, the cognitive revolution has had enormous impact. Similarly, among biologists, the Darwinian revolution has had enormous impact. The major theme of this chapter is that these two scientific research programs need to be combined into a single approach, simultaneously cognitive and Darwinian, and that this single approach is most appropriately called cognitive ethology.

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Preface: Animal Cognition In Nature, Russell P. Balda, Irene M. Pepperberg, Alan Kamil Jan 1998

Preface: Animal Cognition In Nature, Russell P. Balda, Irene M. Pepperberg, Alan Kamil

Papers in Behavior in Biological Sciences

This volume, Animal Cognition in Nature, is the result of an ongoing synthesis of several ideas that were considered revolutionary, if not heretical, in the 1960s. At that time, animal behavior, whether studied in field or laboratory, by ethologists or psychologists, was generally interpreted as the result of simple processes relating specific stimuli to specific behaviors. Examples from that time include S–R models, sign stimuli, IRMs, etc. Theoretical constructs such as mental representations, memory or attention were avoided. Today, students of animal behavior work in an entirely different atmosphere. This is the result of several developments.

One of these developments …

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Telomerase Expression In Chickens: Constitutive Activity In Somatic Tissues And Down-Regulation In Culture, Ranga N. Venkatesan, Carolyn Price Jan 1998

Telomerase Expression In Chickens: Constitutive Activity In Somatic Tissues And Down-Regulation In Culture, Ranga N. Venkatesan, Carolyn Price

Department of Biochemistry: Faculty Publications

Although human and rodent telomeres have been studied extensively, very little is known about telomere dynamics in other vertebrates. Moreover, our current dependence on mice as a model for human tumorigenesis and aging poses a problem because human and mouse telomere biology is very different. To explore whether chickens might provide a more useful model, we have examined telomerase activity and telomere length in chicken tissues as well as in primary cell cultures. Although chicken telomeres resemble human telomeres in that they are 8–20 kb in length, the distribution of telomerase activity in chickens resembles what is found in mice. …

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Purification And Characterization Of A Soybean Root Nodule Phosphatase Expressed In Pichia Pastoris, Alan R. Penheiter, Robert V. Klucas, Gautam Sarath Jan 1998

Purification And Characterization Of A Soybean Root Nodule Phosphatase Expressed In Pichia Pastoris, Alan R. Penheiter, Robert V. Klucas, Gautam Sarath

Gautam Sarath Publications

Soybean root nodules possess a developmentally regulated acid phosphatase (ACP) that exhibits the highest specificity for purine 5’-nucleoside monophosphates. The enzyme is a glycosylated dimer of 28- and 31-kDa subunits, which appear to be products of the same gene but differ in posttranslational modifications. In order to perform directed mutagenesis and more extensive biochemical characterization, a means of producing recombinant ACP was needed. Several attempts were made to express ACP in Escherichia coli, but all conditions employed resulted in protein that was found entirely in inclusion bodies, and resolubilization experiments were unsuccessful. Therefore, the methyltrophic yeast Pichia pastoris was …

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Differential Gene Expression In Insects: Transcriptional Control, Lawrence G. Harshman, Anthony A. James Jan 1998

Differential Gene Expression In Insects: Transcriptional Control, Lawrence G. Harshman, Anthony A. James

School of Biological Sciences: Faculty Publications

Studies on transcriptional control of gene expression play a pivotal role in many areas of biology. In non-Drosophilid insects, the cuticle, chorion, immune response, silk gland, storage proteins, and vitellogenin are foci for advances in basic research on promoter elements and transcription factors. Insects offer other advantages for gene regulation studies, including the availability of applied problems. In non-Drosophilid insects, the most serious problem for transcriptional control studies is the lack of homologous in vivo expression systems. Once this deficiency is addressed, the full impact of research on transcription control will be realized throughout the field of entomology.

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Life-History Decisions Under Predation Risk: Importance Of A Game Perspective, Amos Bouskila, Michael E. Robinson, Bernard D. Roitberg, Brigitte Tenhumberg Jan 1998

Life-History Decisions Under Predation Risk: Importance Of A Game Perspective, Amos Bouskila, Michael E. Robinson, Bernard D. Roitberg, Brigitte Tenhumberg

School of Biological Sciences: Faculty Publications

We model ontogenetic shifts (e.g. in food or habitat use) during development under predation risk. We ask whether inclusion of state and frequency dependence will provide new insights when compared with game-free life-history theory. We model a simple biological scenario in which a prey animal must switch from a low-predation, low-growth habitat to a high-predation, high-growth habitat. To assess the importance of frequency dependence, we compare the results of four scenarios of increasing complexity: (1) no predation; (2) constant predation; (3) frequency-dependent predation (predation risk diluted at high prey density); and (4) frequency-dependent predation as in (3) but with predators …

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Population Biology Of Intraspecific Polyploidy In Grasses, Kathleen H. Keeler Jan 1998

Population Biology Of Intraspecific Polyploidy In Grasses, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Polyploidy is the duplication of an entire nuclear genome, whether diploid or higher level (Stebbins, 1971; Thompson and Lumaret, 1992) and a frequent occurrence in plants. Stebbins (1971) estimated that 30-35% of flowering plant species are polyploid, and that many more had a polyploid event in their evolutionary history, including all members of such important families as the Magnoliaceae, Salicaceae, and Ericaceae. Goldblatt (1980) estimated 55%, but probably up to 75%, of monocotyledons had at least one polyploid event in their history, using the criterion that if the species has a base number higher than n = 13 it is …

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Roles Of Dnak And Rpos In Starvation-Induced Thermotolerance Of Escherichia Coli, David Rockabrand, Kevin Livers, Tess Austin, Robyn Kaiser, Debra Jensen, Richard Burgess, Paul H. Blum Jan 1998

Roles Of Dnak And Rpos In Starvation-Induced Thermotolerance Of Escherichia Coli, David Rockabrand, Kevin Livers, Tess Austin, Robyn Kaiser, Debra Jensen, Richard Burgess, Paul H. Blum

School of Biological Sciences: Faculty Publications

DnaK is essential for starvation-induced resistance to heat, oxidation, and reductive division in Escherichia coli. Studies reported here indicate that DnaK is also required for starvation-induced osmotolerance, catalase activity, and the production of the RpoS-controlled Dps (PexB) protein. Because these dnaK mutant phenotypes closely resemble those of rpoS (o38) mutants, the relationship between DnaK and RpoS was evaluated directly during growth and starvation at 30°C in strains with genetically altered DnaK content. A starvation-specific effect of DnaK on RpoS abundance was observed. During carbon starvation, DnaK deficiency reduced RpoS levels threefold, while DnaK excess increased RpoS levels …

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Molecular Characterization Of The Α-Glucosidase Gene (Mala) From The Hyperthermophilic Archaeon Sulfolobus Solfataricus, Michael Rolfsmeier, Cynthia Haseltine, Elisabetta Bini, Amy Clark, Paul H. Blum Jan 1998

Molecular Characterization Of The Α-Glucosidase Gene (Mala) From The Hyperthermophilic Archaeon Sulfolobus Solfataricus, Michael Rolfsmeier, Cynthia Haseltine, Elisabetta Bini, Amy Clark, Paul H. Blum

School of Biological Sciences: Faculty Publications

Acidic hot springs are colonized by a diversity of hyperthermophilic organisms requiring extremes of temperature and pH for growth. To clarify how carbohydrates are consumed in such locations, the structural gene (malA) encoding the major soluble α-glucosidase (maltase) and flanking sequences from Sulfolobus solfataricus were cloned and characterized. This is the first report of an α-glucosidase gene from the archaeal domain. malA is 2,083 bp and encodes a protein of 693 amino acids with a calculated mass of 80.5 kDa. It is flanked on the 5’ side by an unusual 1-kb intergenic region. Northern blot analysis of the …

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Population Growth Of Rhinocyllus Conicus (Coleoptera: Curculionidae) On Two Species Of Native Thistles In Prairie, Svata M. Louda Jan 1998

Population Growth Of Rhinocyllus Conicus (Coleoptera: Curculionidae) On Two Species Of Native Thistles In Prairie, Svata M. Louda

Svata M. Louda Publications

The insect Rhinocyllus conicus Froehlich is a flowerhead weevil deliberately introduced into the United States for the biological control of invasive exotic thistles in the genus Carduus. This study documents the course and magnitude of the weevil population expansion onto nontarget host plants. No weevils were reared from either Platte thistle, Cirsium canescens Nuttall, or wavyleaf thistle, C. undulatum (Nuttall) Sprengel, from 1977 to 1993 at 2 Sandhills prairie preserves: Arapaho Prairie and Niobrara Valley. For Platte thistle, the number of both R. conicus adults on plants and the number of larvae developing in flowerheads increased significantly from 1993 …

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Cytoskeletal Association Of An Esterase In Dictyostelium Discoideum, Catherine P. Chia, Lothar Bomblies, Kristy K. Taylor Jan 1998

Cytoskeletal Association Of An Esterase In Dictyostelium Discoideum, Catherine P. Chia, Lothar Bomblies, Kristy K. Taylor

Papers in Microbiology

A 70-kDa glycoprotein, gp70, was found enriched in the detergentinsoluble cytoskeletal fraction of axenically grown Dictyostelium discoideum cells. Its N-terminal amino acid sequence identified it as “crystal protein” (L. Bomblies et al., 1990, J. Cell Biol. 110, 669– 679). This finding was corroborated when antibody to crystal protein cross-reacted with gp70 and its deglycosylated form. The postulated esterase activity of gp70/crystal protein was verified through comparative enzyme assays of extracts derived from cells that either overexpressed or lacked gp70. Gp70 cosedimented with cytoskeletons on sucrose gradients, suggesting an interaction with the cytoskeleton. Coisolation of gp70 with detergent-extracted cells, observed by …

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Exercise Capacity Of House Wren Nestlings: Chicks Are Not Working As Hard As They Can, Mark A. Chappell, Gwendolyn C. Bachman Jan 1998

Exercise Capacity Of House Wren Nestlings: Chicks Are Not Working As Hard As They Can, Mark A. Chappell, Gwendolyn C. Bachman

Papers in Behavior in Biological Sciences

We measured the aerobic capacity for exercise in house wren (Troglodytes aedon) nestlings from 3 to 10 days of age. Exercise data were compared with previous measurements of the energy cost of begging (Ebeg) to determine if begging chicks are working at maximal exercise capacity. We also compared exercise with the peak metabolic rate during digestion and, in older chicks, with thermogenic heat production. Rates of oxygen consumption (VO2) during exercise increased rapidly with age, but the factorial aerobic scope for exercise (exercise VO2/resting VO2) averaged only 1.4 (at three …

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The Effect Of Background Cuing On Prey Detection, Henry Kono, Pamela J. Reid, Alan Kamil Jan 1998

The Effect Of Background Cuing On Prey Detection, Henry Kono, Pamela J. Reid, Alan Kamil

Papers in Behavior in Biological Sciences

Studies of prey detection have typically focused on how search image affects the capture of cryptic items. This study also considers how background vegetation influences cryptic prey detection. Blue jays, Cyanocitta cristata, searched digitized images for two Catocala moths: C. ilia, which is cryptic on oak, and C. relicta, which is cryptic on birch. Some images contained moths while others did not. The ability of blue jays to detect prey during repeated presentations of one prey type within a session was compared with their performance during randomly alternating presentations of both prey types within a session to …

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Metazoan Parasites And Other Symbionts Of Cetaceans In The Caribbean, Antonio A. Mignucci-Giannoni, Eric P. Hoberg, Doug Siegel-Causey, Ernest H. Williams Jr. Jan 1998

Metazoan Parasites And Other Symbionts Of Cetaceans In The Caribbean, Antonio A. Mignucci-Giannoni, Eric P. Hoberg, Doug Siegel-Causey, Ernest H. Williams Jr.

Harold W. Manter Laboratory of Parasitology: Faculty Publications

The parasite fauna in cetaceans from Puerto Rico, the Virgin Islands, and the larger Caribbean region is poorly known. We provide the first records for parasite biodiversity among a diverse assemblage of cetaceans from the Caribbean Sea. Internal and external parasites and commensals were collected from stranded whales and dolphins salvaged in Puerto Rico, the United States and British Virgin Islands, Jamaica, and Venezuela between 1989 and 1997. A total of 47 individuals of 16 species of whales and dolphins (15 odontocetes and one mysticete) were examined. Overall, parasites and commensals were found in 34 (72.3%) animals, representing 13 species …

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The Identification And Characteristics Of Echinoparyphium Rubrum (Cort, 1914) Comb. New (Trematoda, Echinostomatidae) Based On Experimental Evidence Of The Life Cycle, Ivan Kanev, Robert Sorensen, Mauritz Strerner, Rebecca Cole, Bernard Fried Jan 1998

The Identification And Characteristics Of Echinoparyphium Rubrum (Cort, 1914) Comb. New (Trematoda, Echinostomatidae) Based On Experimental Evidence Of The Life Cycle, Ivan Kanev, Robert Sorensen, Mauritz Strerner, Rebecca Cole, Bernard Fried

Harold W. Manter Laboratory of Parasitology: Faculty Publications

The life cycle of Echinoparyphium rubrum (Cort, 1914) comb. n. has been completed experimentally. All of the developmental stages - egg, miracidium, sporocyst, mother and daughter rediae, cercaria, metacercaria, and adult - were examined and described. The miracidia infected freshwater snails of the genus Physa, P. gyrina and P. occidentalis. Attempts to infect snails of the genera Lymnaea, L. auricularis, L. peregra. L. truncatula and Bulinus, B. truncatus failed. Cercariae infected various pulmonate and prosobranch freshwater snails, mussels, frogs, water turtles and planarians. The adults developed in the small intestine of birds and mammals. The identity and major characteristics of …

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Metathesis-Based Synthesis Of Jasmonate And Homojasmonate Lactones, Candidates For Extracellular Quorum Sensing Molecules In Candida Albicans, Su C. Cho, Patrick Dussault, Amber D. Lisec, Ellen C. Jensen, Kenneth W. Nickerson Jan 1998

Metathesis-Based Synthesis Of Jasmonate And Homojasmonate Lactones, Candidates For Extracellular Quorum Sensing Molecules In Candida Albicans, Su C. Cho, Patrick Dussault, Amber D. Lisec, Ellen C. Jensen, Kenneth W. Nickerson

Department of Chemistry: Faculty Publications

Ring-closing metathesis of jasmonate esters is shown to provide a rapid entry to jasmonate lactones. The lactones were investigated as possible quorum sensing molecules for the fungi Candida albicans. Assays demonstrated no effect on fungal morphology at concentrations up to 96 mM.

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Biodiesel Fuel From Animal Fat. Ancillary Studies On Transesterification Of Beef Tallow, Fangrui Ma, L. Davis Clements, Milford Hanna Jan 1998

Biodiesel Fuel From Animal Fat. Ancillary Studies On Transesterification Of Beef Tallow, Fangrui Ma, L. Davis Clements, Milford Hanna

Nebraska Center for Biotechnology: Faculty and Staff Publications

Transesterification of beef tallow was investigated. The solubility of ethanol in beef tallow was much higher than that of methanol. At 100 °C the solubility of methanol was 19% (w/w). The solubility of ethanol in beef tallow reached 100% (w/w) at about 68 °C. For the distribution of methanol between beef tallow methyl esters (BTME) and glycerol, the percentage of total methanol in the glycerol phase was higher than that in the fatty acid methyl ester (FAME) phase in a simulated system at room temperature. At 65-80 °C, however, the percentage of total methanol in FAME (60% (w/w)) was higher …

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Mummies And Mummification Practices In The Southern And Southwestern United States, Mahmoud Y. El-Najjar, Thomas M. J. Mulinski, Karl Reinhard Jan 1998

Mummies And Mummification Practices In The Southern And Southwestern United States, Mahmoud Y. El-Najjar, Thomas M. J. Mulinski, Karl Reinhard

Karl Reinhard Publications

Mummification was not intentional for most North American prehistoric cultures. Natural mummification occurred in the dry areas of North America, where mummies have been recovered from rock shelters, caves, and overhangs. In these places, corpses desiccated and spontaneously mummified. In North America, mummies are recovered from four main regions: the southern and southwestern United States, the Aleutian Islands, and the Ozark Mountains of Arkansas. This chapter is limited to a discussion of burial practices and a tabulation of the location of mummies in the southwestern United States with some comments on mummies of the southern United States, including the Ozarks.

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New Investigative Techniques [In Mummies, Disease & Ancient Cultures], Theodore A. Reyman, Henrick Nielsen, Ingolf Thuesen, Derek N. H. Notman, Karl Reinhard, Edmund Tapp, Tony Waldron Jan 1998

New Investigative Techniques [In Mummies, Disease & Ancient Cultures], Theodore A. Reyman, Henrick Nielsen, Ingolf Thuesen, Derek N. H. Notman, Karl Reinhard, Edmund Tapp, Tony Waldron

Karl Reinhard Publications

In this chapter, we shall see how the amplification of minute amounts of genetic material by the polymerase chain reaction (PCR) has enabled researchers to identifY both native and infectious DNA in these bodies. The use of amplified bacterial and viral DNA may turn out to be Aidan Cockburn's 'magic bullet' for solving some of the mysteries of infectious disorders in ancient populations. In the same fashion, native DNA may give us clues to a variety of genetic abnormalities that existed in those distant times. These newer techniques will be the focus of the revised technical section in this second …

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Human Dental Microwear Caused By Calcium Oxalate Phytoliths In Prehistoric Diet Of The Lower Pecos Region, Texas, Dennis Danielson, Karl Reinhard Jan 1998

Human Dental Microwear Caused By Calcium Oxalate Phytoliths In Prehistoric Diet Of The Lower Pecos Region, Texas, Dennis Danielson, Karl Reinhard

Karl Reinhard Publications

Recent research demonstrates that silica phytoliths of dietary origin are associated with microwear of human teeth. Previous research has shown that severe enamel microwear and dental wear characterizes Archaic hunter-gatherers in the lower Pecos region of west Texas. Calcium oxalate crystals are especially common in Archaic coprolites. The vast majority are derived from prickly pear and agave, which were the dietary staples in west Texas for 6,000 years. The calcium oxalate phytoliths are harder than enamel. Therefore, calcium oxalate crystals are the most likely source of previously documented dental microwear and wear in the lower Pecos region.Am J Phys Anthropol …

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Book Review Of Paleolimnology Of Europeanmaar Lakes By J. F.W. Negendank & B. Zolitschka (Eds)., J. Platt Bradbury Jan 1998

Book Review Of Paleolimnology Of Europeanmaar Lakes By J. F.W. Negendank & B. Zolitschka (Eds)., J. Platt Bradbury

United States Geological Survey: Staff Publications

This book represents a collection of papers presented at a symposium in May, 1991 on the formation and paleolimnology of European maar lakes. Paleolimnological discussions embrace maar lake deposits of late Quaternary to early Tertiary age in Germany, France and Italy. The goal of the symposium and its outgrowth, this book, is to develop a funding initiative to study, core and analyze the deposits of these remarkable depositional systems.

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Early Life History Stages Of Gulf Sturgeon In The Suwannee River, Florida, Kenneth J. Sulak, James P. Clugston Jan 1998

Early Life History Stages Of Gulf Sturgeon In The Suwannee River, Florida, Kenneth J. Sulak, James P. Clugston

United States Geological Survey: Staff Publications

Egg sampling confirmed that Suwannee River Gulf sturgeon Acipenser ozyrinchus desotoi, a subspecies of Atlantic sturgeon A. o. oxyrinchus use the same spawning site at river kilometer (rkm) 215 from the mouth of the river each year. Forty-nine eggs were recorded in 1995, and 368 were recorded in 1996. Spawning began 4-7 d after the March new moon in both years and lasted 10-11 d; in 1996, a second 10-d spawning round began on the April new moon. Developmental synchrony among eggs recovered suggested serval discrete spawning events in both years. Total eggs deposited for three 1996 sampling days …

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15. Florida Keys Community College Jan 1998

15. Florida Keys Community College

Florida Library History Project

A history of Florida Keys Community College in Key West, Florida.

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