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Phytochrome Evolution In Green And Nongreen Plants, Sarah Mathews May 2005

Phytochrome Evolution In Green And Nongreen Plants, Sarah Mathews

Faculty Publications

Photoreceptors are critical molecules that function at the interface between organism and environment. Plants use specific light signals to determine their place in time and space, allowing them to synchronize their growth, metabolism, and development to the environments in which they occur. Thus, innovation in light sensing mechanisms is expected to coincide with adaptation and diversification. Three studies involving the well-characterized phytochrome photoreceptor system in plants indicate that much work is yet needed to test this expectation. In early diverging dowering plants, episodic positive selection influenced the evolution of phytochrome A, but little of the functional data needed to link …


Hibernation Is Recorded In Lower Incisors Of Recent And Fossil Ground Ssquirrels (Spermophilus), Tom Goodwin, Gail R. Michener, Daniel Gonzalez, Caroline E. Rinaldi Apr 2005

Hibernation Is Recorded In Lower Incisors Of Recent And Fossil Ground Ssquirrels (Spermophilus), Tom Goodwin, Gail R. Michener, Daniel Gonzalez, Caroline E. Rinaldi

Faculty Publications

Incremental dentin and associated enamel, features visible on the surface of lower incisors, were characterized for 3 species of ground squirrels (Spermophilus): Pleistocene and Recent S. elegans, Recent S. richardsonii, and Recent S. parryii. A hibernation mark was evident in incisor dentin and enamel, most characteristically as a sleeve of enamel terminating basally adjacent to medially depressed dentin with indistinct and often very fine increments. This mark was absent in juveniles but present in older animals of both sexes for at least 6 weeks after hibernation, eventually being lost through growth and wear of the incisor. Temporal association with hibernation …


Home-Range Size, Response To Fire, And Habitat Preferences Of Wintering Henslow's Sparrows, Catherine L. Bechtoldt, Philip C. Stouffer Jan 2005

Home-Range Size, Response To Fire, And Habitat Preferences Of Wintering Henslow's Sparrows, Catherine L. Bechtoldt, Philip C. Stouffer

Faculty Publications

Henslow's Sparrow (Ammodramus henslowii) is a declining, disturbance-dependent grassland bird that winters in the longleaf pine (Pinus palustris) ecosystem of the southeastern United States. During two winters (2001, 2002), we estimated the relative abundances, movement patterns, and habitat associations of Henslow's Sparrows wintering in habitat patches differing in time since last burn (burn treatment). We conducted our study in southeastern Louisiana in Andropogon spp.-dominated longleaf pine savanna habitat. Henslow's Sparrows were most abundant in savannas burned the previous growing season, with a mean relative abundance of 2.6 individuals/ha. The most dramatic decline occurred between burn year 0 and year 1 …


Molecular Analysis Of Carbon Monoxide-Oxidizing Bacteria Associated With Recent Hawaiian Volcanic Deposits, Kari E. Dunfield, Gary M. King Jul 2004

Molecular Analysis Of Carbon Monoxide-Oxidizing Bacteria Associated With Recent Hawaiian Volcanic Deposits, Kari E. Dunfield, Gary M. King

Faculty Publications

Genomic DNA extracts from four sites at Kilauea Volcano were used as templates for PCR amplification of the large subunit (coxL) of aerobic carbon monoxide dehydrogenase. The sites included a 42-year-old tephra deposit, a 108-year-old lava flow, a 212-year-old partially vegetated ash-and-tephra deposit, and an approximately 300-year-old forest. PCR primers amplified coxL sequences from the OMP clade of CO oxidizers, which includes isolates such as Oligotropha carboxidovorans, Mycobacterium tuberculosis, and Pseudomonas thermocarboxydovorans. PCR products were used to create clone libraries that provide the first insights into the diversity and phylogenetic affiliations of CO oxidizers in situ. On the basis of …


Rationale For A New Generation Of Indicators For Coastal Waters, Gerald Niemi, Denice Wardrop, Robert Brooks, Susan Anderson, Valerie Brady, Hans Paerl, Chet Rakocinski, Marius Brouwer, Barbara Levinson, Michael Mcdonald Jun 2004

Rationale For A New Generation Of Indicators For Coastal Waters, Gerald Niemi, Denice Wardrop, Robert Brooks, Susan Anderson, Valerie Brady, Hans Paerl, Chet Rakocinski, Marius Brouwer, Barbara Levinson, Michael Mcdonald

Faculty Publications

More than half the world'S human population lives within 100 km of the coast, and that number is expected to increase by 25% over the next two decades. Consequently, coastal ecosystems are at serious risk. Larger coastal populations and increasing development have led to increased loading of toxic substances, nutrients and pathogens with subsequent algal blooms, hypoxia, beach closures, and damage to coastal fisheries. Recent climate change has led to the rise in sea level with loss of coastal wetlands and saltwater intrusion into coastal aquifers. Coastal resources have traditionally been monitored on a stressor-by-stressor basis such as for nutrient …


Mediation Of Host Selection And Oviposition Behavior In The Diamondback Moth Plutella Xylostella And Its Predator Chrysoperla Carnea By Chemical Cues From Cole Crops, G. V.P. Reddy, E. Tabone, M. T. Smith Jan 2004

Mediation Of Host Selection And Oviposition Behavior In The Diamondback Moth Plutella Xylostella And Its Predator Chrysoperla Carnea By Chemical Cues From Cole Crops, G. V.P. Reddy, E. Tabone, M. T. Smith

Faculty Publications

Host plant-mediated orientation and oviposition by diamondback moth (DBM) Plutella xylostella (L.) (Lepidoptera: Yponomeutidae) and its predator Chrysoperla carnea Stephens (Neuroptera: Chrysopidae) were studied in response to four different brassica host plants: cabbage, (Brassica oleracea L. subsp. capitata), cauliflower (B. oleracea L. subsp. botrytis), kohlrabi (B. oleracea L. subsp. gongylodes), and broccoli (B. oleracea L. subsp. italica). Results from laboratory wind tunnel studies indicated that orientation of female DBM and C. carnea females towards cabbage and cauliflower was significantly greater than towards either broccoli or kohlrabi plants. However, DBM and C. carnea males did not orient towards any of the …


Summer Activity Of Small Snakes In Four Habitats In Northwestern Missouri, L. D. Johnson, Geoffrey R. Smith, Jessica E. Rettig Jan 2004

Summer Activity Of Small Snakes In Four Habitats In Northwestern Missouri, L. D. Johnson, Geoffrey R. Smith, Jessica E. Rettig

Faculty Publications

No abstract provided.


Molecular And Culture-Based Analyses Of Aerobic Carbon Monoxide Oxidizer Diversity, Gary M. King Dec 2003

Molecular And Culture-Based Analyses Of Aerobic Carbon Monoxide Oxidizer Diversity, Gary M. King

Faculty Publications

Isolates belonging to six genera not previously known to oxidize CO were obtained from enrichments with aquatic and terrestrial plants. DNA from these and other isolates was used in PCR assays of the gene for the large subunit of carbon monoxide dehydrogenase (coxL). CoxL and putative coxL fragments were amplified from known CO oxidizers (e.g., Oligotropha carboxidovorans and Bradyrhizobium japonicum), from novel CO-oxidizing isolates (e.g., Aminobacter sp. strain COX, Burkholderia sp. strain LUP, Mesorhizobium sp. strain NMB1, Stappia strains M4 and M8, Stenotrophomonas sp. strain LUP, and Xanthobacter sp. strain COX), and from several well-known isolates for which the capacity …


Predicting Severe Wildfire Years In The Florida Everglades, Brian Beckage, William J. Platt Jun 2003

Predicting Severe Wildfire Years In The Florida Everglades, Brian Beckage, William J. Platt

Faculty Publications

© 2003 The Ecological Society of America. Wildfires result in important ecological benefits to many ecosystems, but have costs associated with fire fighting and property loss. Accurate, timely forecasts of the severity of upcoming wildfire seasons could facilitate wildfire management, limiting the most destructive aspects of fires, while preserving their ecological benefits. We demonstrate an approach where time series models are used to predict the severity of the wildfire season in Everglades National Park in southern Florida 3 months and 1 year beforehand. Model predictions contained all obserations within a 90% credible interval and also anticipated severe wildfire seasons. These …


Nature Writing, American Literature, And The Idea Of Community: A Conversation With Barry Lopez, David Thomas Sumner Jan 2001

Nature Writing, American Literature, And The Idea Of Community: A Conversation With Barry Lopez, David Thomas Sumner

Faculty Publications

This interview with Barry Lopez is part of a series of conversations with contemporary western writers about the ethical and cultural implications of nature writing.


Comparison Of Tovs-Derived Land Surface Variables With Ground Observations, Venkataraman Lakshmi, Joel Susskind Jan 2000

Comparison Of Tovs-Derived Land Surface Variables With Ground Observations, Venkataraman Lakshmi, Joel Susskind

Faculty Publications

The Tiros Operational Vertical Sounder (TOVS) Pathfinder Path A retrieved surface skin temperature, surface air temperatures, and surface specific humidity are compared with data obtained from three large-scale field campaigns: the First ISLSCP (International Satellite Land Surface Climatology Project) Field Experiment (FIFE), the Hydrologic Atmospheric Pilot Experiment (HAPEX) in the Sahel, and the Boreal Ecosystem-Atmosphere Study (BOREAS). The long-term estimates of surface skin temperatures, surface air temperatures, and surface vapor pressure were unbiased, and the standard deviations of the errors were about 4°C, 3.5°C, and 3.5 mbar, respectively. The monthly mean variables obtained from the TOVS data at four times …


Delineating Relative Temperature Zones In Forest Ecosystems: An Adaptation And Evaluation Of Current Methodologies, Daniel Unger, J.J. Ulliman Jan 2000

Delineating Relative Temperature Zones In Forest Ecosystems: An Adaptation And Evaluation Of Current Methodologies, Daniel Unger, J.J. Ulliman

Faculty Publications

The effectiveness of using: (1) thermal infrared data; (2) potential solar radiation: and. (3) predicted temperature for mapping relative temperature zones in forest ecosystems were evaluated as tools for forest ecology studies.

The computer simulation models SOLAR and MTCLIM were found to be ineffective for mapping relative forest ecosystem temperature zones. SOLAR-calculated potential solar radiation and MTCLIM-predicted temperature were found to be statistically uncorrelated with coincident mean maximum daily forest ecosystem ambient air temperature recorded within the University of Idaho Experimental Forest during June and July, 1993. Landsat Thematic Mapper thermal infrared data were shown to be effective for mapping …


Home Ranges Of Rat Snakes (Colubridae: Elaphe) In Different Habitats, Stephen J. Mullin, William H. N. Gutzke, Gary D. Zenitsky, Robert J. Cooper Jan 2000

Home Ranges Of Rat Snakes (Colubridae: Elaphe) In Different Habitats, Stephen J. Mullin, William H. N. Gutzke, Gary D. Zenitsky, Robert J. Cooper

Faculty Publications

Based on our findings, we suggest that rat snakes represent not only a major predator of kites, but also of other canopy and mid-story nesting species in the southeastern United States. For example, rat snakes are the most dominant snake nest predator of bird nests throughout the Southeast (DeGregorio et al. 2014) and are skilled tree climbers that often occupy arboreal habitats (Jackson 1976, Keller and Heske 2000, Sperry et al. 2009), particularly in bottomland forests (Mullin et al. 2000, Carfagno and Weatherhead 2009). Thus, the role of rat snakes as predators of nests above the understory is likely underappreciated …


Positive Selection And Propeptide Repeats Promote Rapid Interspecific Divergence Of A Gastropod Sperm Protein, Michael E. Hellberg, Gary W. Moy, Victor D. Vacquier Jan 2000

Positive Selection And Propeptide Repeats Promote Rapid Interspecific Divergence Of A Gastropod Sperm Protein, Michael E. Hellberg, Gary W. Moy, Victor D. Vacquier

Faculty Publications

Male-specific proteins have increasingly been reported as targets of positive selection and are of special interest because of the role they may play in the evolution of reproductive isolation. We report the rapid interspecific divergence of cDNA encoding a major acrosomal protein of unknown function (TMAP) of sperm from five species of teguline gastropods. A mitochondrial DNA clock (calibrated by congeneric species divided by the Isthmus of Panama) estimates that these five species diverged 2-10 MYA. Inferred amino acid sequences reveal a propeptide that has diverged rapidly between species. The mature protein has diverged faster still due to high nonsynonymous …


Spatio-Temporal Distribution Of Larval Gobiosoma Bosc In Waters Adjacent To Natural And Altered Marsh-Edge Habitats Of Mississippi Coastal Waters, J. Read Hendon, Mark S. Peterson, Bruce H. Comyns Jan 2000

Spatio-Temporal Distribution Of Larval Gobiosoma Bosc In Waters Adjacent To Natural And Altered Marsh-Edge Habitats Of Mississippi Coastal Waters, J. Read Hendon, Mark S. Peterson, Bruce H. Comyns

Faculty Publications

Larval naked gobies, Gobiosoma bose, were collected monthly from October 1995 to September 1997 by beam plankton trawl from waters adjacent to natural Juncus/Spartina marsh-edge, natural sandy beach and altered Juncus/Spartina marsh-edge habitats in Mississippi coastal waters. Altered marsh habitats consisted of two bulkheaded stations and one stretch of riprap. Abundances were significantly higher in waters adjacent to natural marsh-edge habitats than in those adjacent to altered habitats in year one (P = 0.011), suggesting that the physical nature of alteration may have caused reduced habitat suitability. Abundances also varied seasonally, with summer conditions of high water temperature, increasing tide …


Relationships Between Overstory Species And Community Classification Of The Sipsey Wilderness, Alabama, Brian P. Oswald, Lianjun Zhang, Thomas Green Jan 1999

Relationships Between Overstory Species And Community Classification Of The Sipsey Wilderness, Alabama, Brian P. Oswald, Lianjun Zhang, Thomas Green

Faculty Publications

A total of 2314 trees was sampled from 170 randomly located plots to investigate ecological community relationships and species similarities of the vegetation covering the 12 000 ha Sipsey Wilderness in Alabama. Thirty-two tree species, 14 vegetation types and 10 landtypes were identi®ed. Within each plot, the species were ranked based on their basal area to determine the relative importance of the species. A variety of species including white oak (Quercus alba L.), post oak (Quercus stellata Wangenh.), chestnut oak (Quercus prinus L.), northern red oak (Quercus rubra L.), red maple (Acer rubrum L.), sugar maple (Acer saccharum Marsh.), loblolly …


Physicochemical Influences On Parasites Of Age-0 Largemouth Bass In The Atchafalaya River Basin, Louisiana, Randy C. Landry, William E. Kelso Jan 1999

Physicochemical Influences On Parasites Of Age-0 Largemouth Bass In The Atchafalaya River Basin, Louisiana, Randy C. Landry, William E. Kelso

Faculty Publications

We investigated prevalence and intensity patterns of nine parasite taxa in 244 age-0 largemouth bass (Micropterus salmoides) collected from lake (high dissolved oxygen levels), riverine (high current velocities), and swamp (hypoxic canals and bayous) sites (N=6) in the Atchafalaya River Basin during the 1996 flood pulse. Ectoparasites were dominated by monogenetic trematodes (prevalence=100%; median intensities 27–91 per host) and glochidia (prevalence > 96% at all sites, median intensities 47–148 per host), whereas Posthodiplostomum minimum (Trematoda), Caecincola spp. (Trematoda; C. parvulus and perhaps C. latostoma), Neoechinorhynchus cylindratus (Acanthocephala), and Proteocephalus ambloplitis (Cestoda) accounted for 94.6% of bass endoparasites. Overall, lake sites supported …


Mapping Monthly Precipitation, Temperature, And Solar Radiation For Ireland With Polynomial Regression And A Digital Elevation Model, Christine L. Goodale, John D. Aber, Scott V. Ollinger Apr 1998

Mapping Monthly Precipitation, Temperature, And Solar Radiation For Ireland With Polynomial Regression And A Digital Elevation Model, Christine L. Goodale, John D. Aber, Scott V. Ollinger

Faculty Publications

A 1 km2 resolution digital elevation model (DEM) of Ireland was constructed and used as the basis for generating digital maps of the climate parameters required to run a model of ecosystem carbon and water cycling. The DEM had mean absolute errors of 30 m or less for most of Ireland. The ecosystem model requires inputs of monthly precipitation, monthly averaged maximum and minimum daily temperature, and monthly averaged daily solar radiation. Long-term (1951 to 1980) averaged monthly data were obtained from sites measuring precipitation (618 sites), temperature (62 sites), and the number of hours of bright sunshine per day …


Sympatric Sea Shells Along The Sea's Shore: The Geography Of Speciation In The Marine Gastropod Tegula, Michael E. Hellberg Jan 1998

Sympatric Sea Shells Along The Sea's Shore: The Geography Of Speciation In The Marine Gastropod Tegula, Michael E. Hellberg

Faculty Publications

Uncertainty and controversy surround the geographical and ecological circumstances that create genetic differences between populations that eventually lead to reproductive isolation. Two aspects of marine organisms further complicate this situation: (1) many species possess planktonic larvae capable of great dispersal; and (2) obvious barriers to movement between populations are rare. Past studies of speciation in the sea have focussed on identifying the effects of past land barriers and on biogeographical breakpoints. However, assessing the role such undeniable barriers actually play in the initial divergence leading to reproductive isolation requires phylogenetic studies of recent radiations living in varying degrees of sympatry …


Epidermal Cell Fate And Patterning In Leaves, John C. Larkin, M. David Marks, Jeanette Nadeau, Fred Sack Jul 1997

Epidermal Cell Fate And Patterning In Leaves, John C. Larkin, M. David Marks, Jeanette Nadeau, Fred Sack

Faculty Publications

No abstract provided.


Velvetbean Caterpillar (Lepidoptera: Noctuidae): Surviving Freezing Weather In Louisiana, Wei Xikui, S. J. Johnson Jan 1995

Velvetbean Caterpillar (Lepidoptera: Noctuidae): Surviving Freezing Weather In Louisiana, Wei Xikui, S. J. Johnson

Faculty Publications

No abstract provided.


A Preliminary Mass Balance Model Of Primary Productivity And Dissolved Oxygen In The Mississippi River Plume/Inner Gulf Shelf Region, Victor J. Bierman Jr., Scott C. Hinz, William J. Wiseman Jr., Nancy N. Rabalais, R. Eugene Turner Dec 1994

A Preliminary Mass Balance Model Of Primary Productivity And Dissolved Oxygen In The Mississippi River Plume/Inner Gulf Shelf Region, Victor J. Bierman Jr., Scott C. Hinz, William J. Wiseman Jr., Nancy N. Rabalais, R. Eugene Turner

Faculty Publications

A deterministic, mass balance model for phytoplankton, nutrients, and dissolved oxygen was applied to the Mississippi River Plume/Inner Gulf Shelf (MRP/IGS) region. The model was calibrated to a comprehensive set of field data collected during July 1990 at over 200 sampling stations in the northern Gulf of Mexico. The spatial domain of the model is represented by a three-dimensional, 21-segment water-column .grid extending from the Mississippi River Delta west to the Louisiana-Texas border, and from the shoreline seaward to the 30-60 m bathymetric contours. Diagnostic analyses and numerical experiments were conducted with the calibrated model to better understand the environmental …


Limnological Aspects Of Upland Island: A Wilderness Area In East Texas, J. A. Sidnell, C W. Reed, J. D. Mccullough Jan 1986

Limnological Aspects Of Upland Island: A Wilderness Area In East Texas, J. A. Sidnell, C W. Reed, J. D. Mccullough

Faculty Publications

No abstract provided.


Floristic Composition And Management Of East Texas Pitcher Plant Bogs, E. S. Nixon, J. R. Ward Jan 1986

Floristic Composition And Management Of East Texas Pitcher Plant Bogs, E. S. Nixon, J. R. Ward

Faculty Publications

No abstract provided.


Natural Areas Of The Southeast, Laurence C. Walker Jan 1963

Natural Areas Of The Southeast, Laurence C. Walker

Faculty Publications

The following article on the status of the natural area program in the Southeastern Section (Alabama, Georgia, and Florida) is condensed from a report summarizing the progress of the Section's liaison officer (Laurence C. Walker) to the National Natural Area Committee. Each Section of our Society has such a liaison officer--some Sections have a natural area committee--who conducts the field work for the National Committee. The goal of the Committee, as well as that of cooperating agencies and organizations, is to locate and to have preserved in perpetuity, for purposes of research and education, examples of undisturbed, natural forests representing …